Front-end Developer Handbook 2019

Front-end Developer Handbook 2019

Sponsored by Frontend Masters, advancing your skills with in-depth, modern front-end engineering courses

Sponsored by Frontend Masters, advancing your skills with in-depth, modern front-end engineering courses

Overview:

This is a guide that everyone can use to learn about the practice of front-end development. It broadly outlines and discusses the practice of front-end engineering: how to learn it and what tools are used when practicing it in 2019.

It is specifically written with the intention of being a professional resource for potential and currently practicing front-end developers to equip themselves with learning materials and development tools. Secondarily, it can be used by managers, CTOs, instructors, and head hunters to gain insights into the practice of front-end development.

The content of the handbook favors web technologies (HTML, CSS, DOM, and JavaScript) and those solutions that are directly built on top of these open technologies. The materials referenced and discussed in the book are either best in class or the current offering to a problem.

The book should not be considered a comprehensive outline of all resources available to a front-end developer. The value of the book is tied up in a terse, focused, and timely curation of just enough categorical information so as not to overwhelm anyone on any one particular subject matter.

The intention is to release an update to the content yearly. This is currently the fourth year an edition has been released.

What is in this Handbook:

Chapter 0 provides a lite recap of the year in front-end development and what may be to come. Chapter 1 & 2 aim to give a brief overview of the discipline and practice of front-end development. Chapters 3 & 4 organize and recommend learning paths and resources. Chapter 5 organizes and list the tools used by front-end developers and Chapter 6 highlights front-end information outlets.

Contribute content, suggestions, and fixes on github:

https://github.com/FrontendMasters/front-end-handbook-2019

Chapter 0. Recap of 2018 and Looking Forward

0.1 — Recap of Front-end Development in 2018

0.2 — In 2019, Expect...

Chapter 1. What Is a Front-end Developer?

This chapter provides a baseline explanation for front-end development and the front-end developer discipline.

Front-end web development, also known as client-side development is the practice of producing HTML, CSS and JavaScript for a website or Web Application so that a user can see and interact with them directly. The challenge associated with front end development is that the tools and techniques used to create the front end of a website change constantly and so the developer needs to constantly be aware of how the field is developing.> The objective of designing a site is to ensure that when the users open up the site they see the information in a format that is easy to read and relevant. This is further complicated by the fact that users now use a large variety of devices with varying screen sizes and resolutions thus forcing the designer to take into consideration these aspects when designing the site. They need to ensure that their site comes up correctly in different browsers (cross-browser), different operating systems (cross-platform) and different devices (cross-device), which requires careful planning on the side of the developer.> https://en.wikipedia.org/wiki/Front-end_web_development
Image source: https://www.upwork.com/hiring/development/front-end-developer/

A Front-end Developer...

A front-end developer architects and develops websites and web applications using web technologies (i.e., HTML, CSS, and JavaScript), which typically runs on the Open Web Platform or acts as compilation input for non-web platform environments (i.e., React Native).

A person enters into the field of front-end development by learning to build a website or web application which relies on HTML, CSS, and JavaScript and commonly runs in a web browser but can also run in a headless browser, WebView, or as compilation input for a native runtime environment. These four run times scenarios are explained below.

Web Browsers (most common)

A web browser is software used to retrieve, present, and traverse information on the WWW. Typically, browsers run on a desktop or laptop computer, tablet, or phone, but as of late a browser can be found on just about anything (i.e, on a fridge, in cars, etc.).

The most common web browsers are (shown in order of most used first):

Headless Browsers

Headless browsers are a web browser without a graphical user interface that can be controlled from a command line interface programmatically for the purpose of web page automation (e.g., functional testing, scraping, unit testing, etc.). Think of headless browsers as a browser that you can run programmatically from the command line that can retrieve and traverse web page code.

The most common headless browsers are:

Webviews

Webviews are used by a native OS, in a native application, to run web pages. Think of a webview like an iframe or a single tab from a web browser that is embedded in a native application running on a device (e.g., iOS, android, windows).

The most common solutions for webview development are:

  • Cordova (typically for native phone/tablet apps)
  • NW.js (typically used for desktop apps)
  • Electron (typically used for desktop apps)

Native from Web Tech

Eventually, what is learned from web browser development can be used by front-end developers to craft code for environments that are not fueled by a browser engine (i.e. web platform). As of late, development environments are being dreamed up that use web technologies (e.g., CSS and JavaScript), without web engines, to create native applications.

Some examples of these environments are:

Notes:

  1. Make sure you are clear what exactly is meant by the "web platform". Read the, ["Open Web Platform"](https://en.wikipedia.org/wiki/Open_Web_Platform ""Open Web Platform"") Wikipedia page. Explore the many technologies that make up the web platform.
Chapter 2. The Practice of Front-end Development: Overview

This chapter will break down and broadly describes the practice of front-end engineering starting with, "How Front-End Developers Are Made".

2.1 - How Front-End Developers Are Made

How exactly does one become a front-end developer? Well, it's complicated. Just consider this road map:

Image source: https://github.com/kamranahmedse/developer-roadmap

Today, in general, one can't go to college and expect to graduate with a degree in front-end engineering. And, I rarely hear of or meet front-end developers who suffered through what is likely a deprecated computer science degree or graphic design degree to end up writing HTML, CSS, and JavaScript professionally. From my perspective, most of the people working on the front-end today generally seem to be self-taught from the ground up or cross over into the front-end space from design or computer science fields.

If you were to set out today to become a front-end developer I would loosely strive to follow the process outlined below (Chapter 3 and Chapter 4 will dive into more details on learning resources).

  1. Learn, roughly, how the web platform works. Make sure you know the "what" and "where" of HTML, CSS, DOM, JavaScript, Domains, DNS, URLs, HTTP, browsers, and servers/hosting. Don't dive deep on anything just yet, just aim to understand the parts at play and how they loosely fit together. Start by building simple web pages.
  2. Learn HTML
  3. Learn CSS
  4. Learn JavaScript
  5. Learn DOM
  6. Learn the fundamentals of user interface design (i.e. UI patterns, interaction design, user experience design, and usability).
  7. Learn CLI/command line
  8. Learn the practice of software engineering (i.e., Application design/architecture, templates, Git, testing, monitoring, automating, code quality, development methodologies).
  9. Get opinionated and customize your tool box with whatever makes sense to your brain (e.g. Webpack, React, and Mobx).
  10. Learn Node.js

A short word of advice on learning. Learn the actual underlying technologies, before learning abstractions. Don't learn jQuery, learn the DOM. Don't learn SASS, learn CSS. Don't learn JSX, learn HTML. Don't learn TypeScript, learn JavaScript. Don't learn Handlebars, learn JavaScript ES6 templates. Don't just use Bootstrap, learn UI patterns.

Lately a lot of non-accredited, expensive, front-end code schools/bootcamps have emerged. These avenues of becoming a front-end developer are typically teacher directed courses, that follow a more traditional style of learning, from an official instructor (i.e., syllabus, test, quizzes, projects, team projects, grades, etc.).

Keep in mind, if you are considering an expensive training program, this is the web! Everything you need to learn is on the web for the taking, costing little to nothing. However, if you need someone to tell you how to take and learn what is low cost to free, and hold you accountable for learning it, you should consider a traditional instructor lead class room setting. Otherwise, I am not aware of any other profession that is practically free for the taking with an internet connection, a couple of dollars a month for screencasting memberships, and a burning desire for knowledge.

For example, if you want to get going today, consuming one or more of the following self-directed resources below can work:

When getting your start, you should fear most things that conceal complexity. Abstractions (e.g. jQuery) in the wrong hands can give the appearance of advanced skills, while all the time hiding the fact that a developer has an inferior understanding of the basics or underlying concepts.

It is assumed that on this journey you are not only learning, but also doing as you learn and investigate tools. Some suggest only doing to learn. While others suggest only learning about doing. I suggest you find a mix of both that matches how your brain works and do that. But, for sure, it is a mix! So, don't just read about it, do it. Learn, do. Learn, do. Repeat indefinitely because things change fast. This is why learning the fundamentals, and not abstractions, are so important.

2.2 - Front-End Job Titles

A great divide has been brewing in the front-end developer space for several years between two very different types of so-called front-end developers. On the one side, you have JavaScript-focused programmers who write JavaScript for front-end runtimes that likely have computer science skills with a software development history. They more than likely view HTML and CSS as an abstraction (i.e. JSX and CSS in JS). On the other side, you have, most likely, non-computer science educated developers who focus on HTML, CSS, and JavaScript as it specifically pertains to the UI. In 2019, when entering or trying to understand the front-end developer space you will absolutely feel this divide. The term front-end developer is on the verge of meaninglessness without clarifying words to address what type of front-end developer is being discussed.

Below is a list and description of various front-end job titles (Keep in mind titles are hard). The common, or most used (i.e., generic), title for a front-end developer is, "front-end developer" or "front-end engineer". Note that any job that contains the word "front-end", "client-side", "web UI", "HTML", "CSS", or "JavaScript" typically infers that a person has some degree of HTML, CSS, DOM, and JavaScript professional know how.

Front-End Developer: The generic job title that describes a developer who is skilled to some degree at HTML, CSS, DOM, and JavaScript and implementing these technologies on the web platform.

Front-End Engineer (aka JavaScript Developer or Full-stack JavaScript Developer): The job title given to a developer who comes from a computer science, engineering, background and is using these skills to work with front-end technologies. This role typically requires computer science knowledge and years of software development experience. When the word "JavaScript Application" is included in the job title, this will denote that the developer should be an advanced JavaScript developer possessing advanced programming, software development, and application development skills (i.e has years of experience building front-end software applications).

CSS/HTML Developer: The front-end job title that describes a developer who is skilled at HTML and CSS, excluding JavaScript and application, know how.

Front-End Web Designer: When the word "Designer" is included in the job title, this will denote that the designer will possess front-end skills (i.e., HTML & CSS) but also professional design (Visual Design and Interaction Design) skills.

UI (User Interface) Developer/Engineer: When the word "Interface" or "UI" is included in the job title, this will denote that the developer should posses interaction design skills in addition to front-end developer skills or front-end engineering skills.

Mobile/Tablet Front-End Developer: When the word "Mobile" or "Tablet" is included in the job title, this will denote that the developer has experience developing front-ends that run on mobile or tablet devices (either natively or on the web platform, i.e., in a browser).

Front-End SEO Expert: When the word "SEO" is included in the job title, this will denote that the developer has extensive experience crafting front-end technologies towards an SEO strategy.

Front-End Accessibility Expert: When the word "Accessibility" is included in the job title, this will denote that the developer has extensive experience crafting front-end technologies that support accessibility requirements and standards.

Front-End Dev. Ops: When the word "DevOps" is included in the job title, this will denote that the developer has extensive experience with software development practices pertaining to collaboration, integration, deployment, automation, and quality.

Front-End Testing/QA: When the word "Testing" or "QA" is included in the job title, this will denote that the developer has extensive experience testing and managing software that involves unit testing, functional testing, user testing, and A/B testing.

Notes:

  1. If you come across the "Full Stack" or the generic "Web Developer" terms in job titles these words may be used by an employer to describe a role that is responsible for all aspects of web/app development, i.e., both front-end (potentially including design) and back-end.

2.3 - Baseline Web Technologies Employed by Front-End Developers

The following core web technologies are employed by front-end developers (consider learning them in this order):

  1. Hyper Text Markup Language (aka HTML)
  2. Cascading Style Sheets (aka CSS)
  3. Uniform Resource Locators (aka URLs)
  4. Hypertext Transfer Protocol (aka HTTP)
  5. JavaScript Programming Language (aka ECMAScript 262)
  6. JavaScript Object Notation (aka JSON)
  7. Document Object Model (aka DOM)
  8. Web APIs (aka HTML5 and friends or Browser APIs)
  9. Web Content Accessibility Guidelines (aka WCAG) & Accessible Rich Internet Applications (aka ARIA)

For a comprehensive list of all web related specifications have a look at platform.html5.org or MDN Web APIs.

The nine technologies just mentioned are defined below along with a link to the relevant documentation and specification for each technology.

Hyper Text Markup Language (aka HTML)

HyperText Markup Language, commonly referred to as HTML, is the standard markup language used to create web pages. Web browsers can read HTML files and render them into visible or audible web pages. HTML describes the structure of a website semantically along with cues for presentation, making it a markup language, rather than a programming language.> — Wikipedia
Most relevant specifications / documentation:

Cascading Style Sheets (aka CSS)

Cascading Style Sheets (CSS) is a style sheet language used for describing the look and formatting of a document written in a markup language. Although most often used to change the style of web pages and user interfaces written in HTML and XHTML, the language can be applied to any kind of XML document, including plain XML, SVG and XUL. Along with HTML and JavaScript, CSS is a cornerstone technology used by most websites to create visually engaging webpages, user interfaces for web applications, and user interfaces for many mobile applications.> — Wikipedia
Most relevant specifications / documentation:

Hypertext Transfer Protocol (aka HTTP)

The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web.> — Wikipedia
Most relevant specifications:

Uniform Resource Locators (aka URL)

A uniform resource locator (URL) (also called a web address) is a reference to a resource that specifies the location of the resource on a computer network and a mechanism for retrieving it. A URL is a specific type of uniform resource identifier (URI), although many people use the two terms interchangeably. A URL implies the means to access an indicated resource, which is not true of every URI. URLs occur most commonly to reference web pages (http), but are also used for file transfer (ftp), email (mailto), database access (JDBC), and many other applications.> — Wikipedia
Most relevant specifications:

Document Object Model (aka DOM)

The Document Object Model (DOM) is a cross-platform and language-independent convention for representing and interacting with objects in HTML, XHTML, and XML documents. The nodes of every document are organized in a tree structure, called the DOM tree. Objects in the DOM tree may be addressed and manipulated by using methods on the objects. The public interface of a DOM is specified in its application programming interface (API).> — Wikipedia
Most relevant specifications / documentation:

JavaScript Programming Language (aka ECMAScript 262)

JavaScript is a high level, dynamic, untyped, and interpreted programming language. It has been standardized in the ECMAScript language specification. Alongside HTML and CSS, it is one of the three essential technologies of World Wide Web content production; the majority of websites employ it and it is supported by all modern web browsers without plug-ins. JavaScript is prototype-based with first-class functions, making it a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles. It has an API for working with text, arrays, dates and regular expressions, but does not include any I/O, such as networking, storage or graphics facilities, relying for these upon the host environment in which it is embedded.> — Wikipedia
Most relevant specifications / documentation:

Web APIs (aka HTML5 and friends)

When writing code for the Web using JavaScript, there are a great many APIs available. Below is a list of all the interfaces (that is, types of objects) that you may be able to use while developing your Web app or site.> — Mozilla
Most relevant documentation:

JavaScript Object Notation (aka JSON)

It is the primary data format used for asynchronous browser/server communication (AJAJ), largely replacing XML (used by AJAX). Although originally derived from the JavaScript scripting language, JSON is a language-independent data format. Code for parsing and generating JSON data is readily available in many programming languages. The JSON format was originally specified by Douglas Crockford. It is currently described by two competing standards, RFC 7159 and ECMA-404. The ECMA standard is minimal, describing only the allowed grammar syntax, whereas the RFC also provides some semantic and security considerations. The official Internet media type for JSON is application/json. The JSON filename extension is .json.> — Wikipedia
Most relevant specifications:

Web Content Accessibility Guidelines (aka WCAG) & Accessible Rich Internet Applications (aka ARIA)

Accessibility refers to the design of products, devices, services, or environments for people with disabilities. The concept of accessible design ensures both “direct access” (i.e., unassisted) and "indirect access" meaning compatibility with a person's assistive technology (for example, computer screen readers).> — Wikipedia* Web Accessibility Initiative (WAI)

2.4 - Potential Front-end Developer Skills

Image source: http://blog.naustud.io/2015/06/baseline-for-modern-front-end-developers.html

A basic to advanced understanding of HTML, CSS, DOM, JavaScript, HTTP/URL, and web browsers is assumed for any type of professional front-end developer role.

Beyond the skills just mentioned, a front-end developer might also be specifically skilled in one or more of the following:

  • Content Management Systems (aka CMS)
  • Node.js
  • Cross-Browser Testing
  • Cross-Platform Testing
  • Unit Testing
  • Cross-Device Testing
  • Accessibility / WAI-ARIA
  • Search Engine Optimization (aka SEO)
  • Interaction or User Interface Design
  • User Experience
  • Usability
  • E-commerce Systems
  • Portal Systems
  • Wireframing
  • CSS Layout / Grids
  • DOM Manipulation (e.g., jQuery)
  • Mobile Web Performance
  • Load Testing
  • Performance Testing
  • Progressive Enhancement / Graceful Degradation
  • Version Control (e.g., GIT)
  • MVC / MVVM / MV*
  • Functional Programming
  • Data Formats (e.g., JSON, XML)
  • Data APIs (e.g Restful API)
  • Web Font Embedding
  • Scalable Vector Graphics (aka SVG)
  • Regular Expressions
  • Microdata / Microformats
  • Task Runners, Build Tools, Process Automation Tools
  • Responsive Web Design
  • Object-Oriented Programming
  • Application Architecture
  • Modules
  • Dependency Managers
  • Package Managers
  • JavaScript Animation
  • CSS Animation
  • Charts / Graphs
  • UI Widgets
  • Code Quality Testing
  • Code Coverage Testing
  • Code Complexity Analysis
  • Integration Testing
  • Command Line / CLI
  • Templating Strategies
  • Templating Engines
  • Single Page Applications
  • Web/Browser Security
  • Browser Developer Tools

2.5 - Front-End Developers Develop For...

A front-end developer crafts HTML, CSS, and JS that typically runs on the web platform (e.g. a web browser) delivered from one of the following operating systems (aka OSs):

These operating systems typically run on one or more of the following devices:

  • Desktop computer
  • Laptop / netbook computer
  • Mobile phone
  • Tablet
  • TV
  • Watch
  • Things (i.e., anything you can imagine, car, refrigerator, lights, thermostat, etc.)

Image source: https://www.enterpriseirregulars.com/104084/roundup-internet-things-forecasts-market-estimates-2015/

Generally speaking, front-end technologies can run on the aforementioned operating systems and devices using the following run time web platform scenarios:

2.6 - Front-End on a Team

A front-end developer is typically only one player on a team that designs and develops web sites, web applications, or native applications running from web technologies.

A bare-bones development team for building professional web sites or software for the web platform will typically, minimally, contain the following roles.

  • Visual Designer (i.e., fonts, colors, spacing, emotion, visuals concepts & themes)
  • UI/Interaction Designer/Information Architect (i.e., wireframes, specifying all user interactions and UI functionality, structuring information)
  • Front-End Developer (i.e., writes code that runs in client/on the device)
  • Back-End Developer (i.e., writes code that runs on the server)

The roles are ordered according to overlapping skills. A front-end developer will typically have a good handle on UI/Interaction design as well as back-end development. It is not uncommon for team members to fill more than one role by taking on the responsibilities of an over-lapping role.

It is assumed that the team mentioned above is being directed by a project lead or some kind of product owner (i.e., stakeholder, project manager, project lead, etc.)

A larger web team might include the following roles not shown above:

  • SEO Strategists
  • DevOps Engineers
  • Performance Engineers
  • API Developers
  • Database Administrators
  • QA Engineers / Testers

2.7 - Generalist/Full-Stack Myth

The term "Full-Stack" developer has come to take on several meanings. So many, that not one meaning is clear when the term is used. Just consider the results from the two surveys shown below. These results might lead one to believe that being a full-stack developer is commonplace. But, in my almost 20 years of experience, this is anything but the case in a professional context.

Image source: https://medium.freecodecamp.com/we-asked-15-000-people-who-they-are-and-how-theyre-learning-to-code-4104e29b2781#.ngcpn8nlz

Image source: https://insights.stackoverflow.com/survey/2017#developer-profile-specific-developer-types

The roles to design and develop a website or web application require a deep set of skills and vast experience in the area of visual design, UI/interaction design, front-end development, and back-end development. Any person who can fill one or more of these 4 roles at a professional level is an extremely rare commodity.

Pragmatically, you should seek to be, or seek to hire, an expert in one of these roles (i.e. Visual Design, Interaction Design/IA, Front-end Dev, Back-end Dev). Those who claim to operate at an expert level at one or more of these roles are exceptionally rare.

However, given that JavaScript has infiltrated all layers of a technology stack (i.e. Node.js) finding a full-stack JS developer who can code the front-end and back-end is becoming less mythical. Typically, these full-stack developers only deal with JavaScript. A developer who can code the front-end, back-end, API, and database isn't as absurd as it once was (excluding visual design, interaction design, and CSS). Still mythical in my opinion, but not as uncommon as it once was. Thus, I wouldn't recommend a developer set out to become a "full-stack" developer. In rare situations, it can work. But, as a general concept for building a career as a front-end developer, I'd focus on front-end technologies.

2.8 - Front-End Interviews

Preparing:

Quiz's:

Questions you may get asked:

Questions you ask:

2.9 - Front-End Job Boards

A plethora of technical job listing outlets exist. The narrowed list below are currently the most relevant resources for finding a specific front-end position/career.

Notes:

  1. Want to work remotely as a front-end developer checkout these remote-friendly companies.

2.10 - Front-End Salaries

The national average in the U.S for a mid-level front-end developer is somewhere between $65k and 100k.

Of course when you first start expect to enter the field at around 40k depending upon location and experience.

Notes:

  1. A lead/senior front-end developer/engineer can potentially live wherever they want (i.e., work remotely) and make over A lead/senior front-end developer/engineer can potentially live wherever they want (i.e., work remotely) and make over $150k a year (visit angel.co, sign-up, review front-end jobs over $150k or examine the salary ranges on Stack Overflow Jobs).50k a year (visit angel.co, sign-up, review front-end jobs over A lead/senior front-end developer/engineer can potentially live wherever they want (i.e., work remotely) and make over $150k a year (visit angel.co, sign-up, review front-end jobs over $150k or examine the salary ranges on Stack Overflow Jobs).50k or examine the salary ranges on Stack Overflow Jobs).
Chapter 3. Learning Front-end Dev: Self Directed Resources/Recommendations

This chapter highlights the many resources (video training, books, etc.) that an individual can use to direct their own learning process and career as a front-end developer.

The learning resources identified (articles, books, videos, screencasts etc..) will include both free and paid material. Paid material will be indicated with [$].

3.1. - Learn Internet/Web

The Internet is a global system of interconnected computer networks that use the Internet protocol suite (TCP/IP) to link several billion devices worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries an extensive range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW), electronic mail, telephony, and peer-to-peer networks for file sharing.> — Wikipedia

Image source: https://www.helloitsliam.com/2014/12/20/how-the-internet-works-infographic/

Image source: http://www.bitrebels.com/technology/find-out-who-runs-the-internet-chart/

3.2. - Learn Web Browsers

A web browser (commonly referred to as a browser) is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier (URI/URL) and may be a web page, image, video or other piece of content. Hyperlinks present in resources enable users easily to navigate their browsers to related resources. Although browsers are primarily intended to use the World Wide Web, they can also be used to access information provided by web servers in private networks or files in file systems.> — Wikipedia#### The most commonly used browsers (on desktop and mobile) are:

  1. Chrome (engine: Blink + V8)
  2. Firefox (engine: Gecko + SpiderMonkey)
  3. Internet Explorer (engine: Trident + Chakra)
  4. Safari (engine: Webkit + SquirrelFish)

Image source: http://gs.statcounter.com/browser-market-share

Evolution of Browsers & Web Technologies (i.e., APIs)

The Most Commonly Used Headless Browser Are:

How Browsers Work

Optimizing for Browsers:

Comparing Browsers

Browser Hacks

Developing for Browsers

In the past, front-end developers spent a lot of time making code work in several different browsers. This was once a bigger issue than it is today. Today, abstractions (e.g., React, Webpack, Post-CSS, Babel etc...) combined with modern browsers make browser development fairly easy. The new challenge is not which browser the user will use, but on which device they will run the browser.

Evergreen Browsers

The latest versions of most modern browsers are considered evergreen browsers. That is, in theory, they are supposed to automatically update themselves silently without prompting the user. This move towards self-updating browsers has been in reaction to the slow process of eliminating older browsers that do not auto-update.

Picking a Browser

As of today, most front-end developers use Chrome and "Chrome Dev Tools" to develop front-end code. However, the most used modern browsers all offer a flavor of developer tools. Picking one to use for development is a subjective choice. The more important issue is knowing which browsers, on which devices, you have to support and then testing appropriately.

3.3 - Learn Domain Name System (aka DNS)

The Domain Name System (DNS) is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities. Most prominently, it translates domain names, which can be easily memorized by humans, to the numerical IP addresses needed for the purpose of computer services and devices worldwide. The Domain Name System is an essential component of the functionality of most Internet services because it is the Internet's primary directory service.> — Wikipedia

Image source: http://www.digital-digest.com/blog/DVDGuy/wp-content/uploads/2011/11/how_dns_works.jpg

3.4 - Learn HTTP/Networks (Including CORS & WebSockets)

HTTP - The Hypertext Transfer Protocol (HTTP) is an application protocol for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web.> — Wikipedia#### HTTP Specifications

HTTP Docs

HTTP Videos/Articles/Tutorials

HTTP Status Codes

CORS - Cross-origin resource sharing (CORS) is a mechanism that allows restricted resources (e.g., fonts) on a web page to be requested from another domain outside the domain from which the resource originated.> — Wikipedia#### CORS Specifications

CORS

WebSockets - WebSocket is a protocol providing full-duplex communication channels over a single TCP connection. The WebSocket protocol was standardized by the IETF as RFC 6455 in 2011, and the WebSocket API in Web IDL is being standardized by the W3C.> — Wikipedia#### WebSockets

3.5 - Learn Web Hosting

A web hosting service is a type of Internet hosting service that allows individuals and organizations to make their website accessible via the World Wide Web. Web hosts are companies that provide space on a server owned or leased for use by clients, as well as providing Internet connectivity, typically in a data center.> — Wikipedia#### General Learning:

Image source: https://firstsiteguide.com/wp-content/uploads/2016/06/what-is-web-hosting-infographic.jpg

3.6 - Learn General Front-End Development

3.7 - Learn User Interface/Interaction Design

User Interface Design - User interface design (UI) or user interface engineering is the design of user interfaces for machines and software, such as computers, home appliances, mobile devices, and other electronic devices, with the focus on maximizing the user experience. The goal of user interface design is to make the user's interaction as simple and efficient as possible, in terms of accomplishing user goals (user-centered design).> — Wikipedia> Interaction Design Pattern - A design pattern is a formal way of documenting a solution to a common design problem. The idea was introduced by the architect Christopher Alexander for use in urban planning and building architecture, and has been adapted for various other disciplines, including teaching and pedagogy, development organization and process, and software architecture and design.> — Wikipedia> User Experience Design - User Experience Design (UXD or UED or XD) is the process of enhancing user satisfaction by improving the usability, accessibility, and pleasure provided in the interaction between the user and the product. User experience design encompasses traditional human–computer interaction (HCI) design, and extends it by addressing all aspects of a product or service as perceived by users.> — Wikipedia> Human–Computer Interaction - Human–computer interaction (HCI) researches the design and use of computer technology, focusing particularly on the interfaces between people (users) and computers. Researchers in the field of HCI both observe the ways in which humans interact with computers and design technologies that lets humans interact with computers in novel ways.> — Wikipedia
Minimally I'd suggest reading the following canonical texts on the matter so one can support and potential build usable user interfaces.

3.8 - Learn HTML & CSS

HTML - HyperText Markup Language, commonly referred to as HTML, is the standard markup language used to create web pages. Web browsers can read HTML files and render them into visible or audible web pages. HTML describes the structure of a website semantically along with cues for presentation, making it a markup language, rather than a programming language.> — Wikipedia> CSS - Cascading Style Sheets (CSS) is a style sheet language used for describing the look and formatting of a document written in a markup language. Although most often used to change the style of web pages and user interfaces written in HTML and XHTML, the language can be applied to any kind of XML document, including plain XML, SVG and XUL. Along with HTML and JavaScript, CSS is a cornerstone technology used by most websites to create visually engaging webpages, user interfaces for web applications, and user interfaces for many mobile applications.> — Wikipedia
Liken to constructing a house, one might consider HTML the framing and CSS to be the painting & decorating.

General Learning:

Mastering CSS:

References/Docs:

Glossary/Vocabulary:

Standards/Specifications:

Architecting CSS:

Authoring/Architecting Conventions:

3.9 - Learn Search Engine Optimization

Search engine optimization (SEO) is the process of affecting the visibility of a website or a web page in a search engine's unpaid results — often referred to as "natural," "organic," or "earned" results. In general, the earlier (or higher ranked on the search results page), and more frequently a site appears in the search results list, the more visitors it will receive from the search engine's users. SEO may target different kinds of search, including image search, local search, video search, academic search, news search and industry-specific vertical search engines.> — Wikipedia

Image source: https://visual.ly/community/infographic/computers/how-does-seo-work

General Learning:

3.10 - Learn JavaScript

JavaScript is a high level, dynamic, untyped, and interpreted programming language. It has been standardized in the ECMAScript language specification. Alongside HTML and CSS, it is one of the three essential technologies of World Wide Web content production; the majority of websites employ it and it is supported by all modern web browsers without plug-ins. JavaScript is prototype-based with first-class functions, making it a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles. It has an API for working with text, arrays, dates and regular expressions, but does not include any I/O, such as networking, storage or graphics facilities, relying for these upon the host environment in which it is embedded.> — Wikipedia#### Getting Started:

General Learning:

Mastering:

Functional JavaScript:

References/Docs:

Glossary/Encyclopedia/Jargon:

Standards/Specifications:

Style:

Deprecated JS Learning Resources:

JS Explorers/Visualizers:

3.11 - Learn DOM, BOM, CSSOM & jQuery

DOM - The Document Object Model (DOM) is a cross-platform and language-independent convention for representing and interacting with objects in HTML, XHTML, and XML documents. The nodes of every document are organized in a tree structure, called the DOM tree. Objects in the DOM tree may be addressed and manipulated by using methods on the objects. The public interface of a DOM is specified in its application programming interface (API).> — Wikipedia> BOM - The Browser Object Model (BOM) is a browser-specific convention referring to all the objects exposed by the web browser. Unlike the Document Object Model, there is no standard for implementation and no strict definition, so browser vendors are free to implement the BOM in any way they wish.> — Wikipedia> jQuery - jQuery is a cross-platform JavaScript library designed to simplify the client-side scripting of HTML. jQuery is the most popular JavaScript library in use today, with installation on 65% of the top 10 million highest-trafficked sites on the Web. jQuery is free, open-source software licensed under the MIT License.> — Wikipedia
The ideal path, but certainly the most difficult, would be to first learn JavaScript, then the DOM, then jQuery. However, do what makes sense to your brain. Most front-end developers learn about JavaScript and then DOM by way of first learning jQuery. Whatever path you take, just make sure JavaScript, the DOM, and jQuery don't become a black box.

General Learning:

Mastering:

References/Docs:

Standards/Specifications:

3.12 - Learn Web Animation

General Learning:

Standards/Specifications:

3.13 - Learn Web Fonts, Icons, & Images

Web typography refers to the use of fonts on the World Wide Web. When HTML was first created, font faces and styles were controlled exclusively by the settings of each Web browser. There was no mechanism for individual Web pages to control font display until Netscape introduced the <font> tag in 1995, which was then standardized in the HTML 3.2 specification. However, the font specified by the tag had to be installed on the user's computer or a fallback font, such as a browser's default sans-serif or monospace font, would be used. The first Cascading Style Sheets specification was published in 1996 and provided the same capabilities.> The CSS2 specification was released in 1998 and attempted to improve the font selection process by adding font matching, synthesis and download. These techniques did not gain much use, and were removed in the CSS2.1 specification. However, Internet Explorer added support for the font downloading feature in version 4.0, released in 1997. Font downloading was later included in the CSS3 fonts module, and has since been implemented in Safari 3.1, Opera 10 and Mozilla Firefox 3.5. This has subsequently increased interest in Web typography, as well as the usage of font downloading.> — Wikipedia#### Fonts:

Icons:

Images:

3.14 - Learn Accessibility

Accessibility refers to the design of products, devices, services, or environments for people with disabilities. The concept of accessible design ensures both “direct access” (i.e., unassisted) and "indirect access" meaning compatibility with a person's assistive technology (for example, computer screen readers).> Accessibility can be viewed as the "ability to access" and benefit from some system or entity. The concept focuses on enabling access for people with disabilities, or special needs, or enabling access through the use of assistive technology; however, research and development in accessibility brings benefits to everyone.> Accessibility is not to be confused with usability, which is the extent to which a product (such as a device, service, or environment) can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use.> Accessibility is strongly related to universal design which is the process of creating products that are usable by people with the widest possible range of abilities, operating within the widest possible range of situations. This is about making things accessible to all people (whether they have a disability or not).> — Wikipedia#### General Learning:

Standards/Specifications:

3.15 - Learn Web/Browser APIs

Image source: http://www.evolutionoftheweb.com/

The BOM (Browser Object Model) and the DOM (Document Object Model) are not the only browser APIs that are made available on the web platform inside of browsers. Everything that is not specifically the DOM or BOM, but an interface for programming the browser could be considered a web or browser API (tragically in the past some of these APIs have been called HTML5 APIs which confuses their own specifics/standardize with the actual HTML5 specification specifying the HTML5 markup language). Note that web or browser APIs do include device APIs (e.g., <a href="https://developer.mozilla.org/en-US/docs/Web/API/Navigator/getBattery" target="_blank">Navigator.getBattery()</a>) that are available through the browser on tablet and phones devices.

You should be aware of and learn, where appropriate, web/browser APIs. A good tool to use to familiarize oneself with all of these APIs would be to investigate the HTML5test.com results for the 5 most current browsers.

MDN has a great deal of information about web/browser APIs.

Keep in mind that not every API is specified by the W3C or WHATWG.

In addition to MDN, you might find the following resources helpful for learning about all the web/browser API's:

3.16 - Learn JSON (JavaScript Object Notation)

JSON, (canonically pronounced sometimes JavaScript Object Notation), is an open standard format that uses human-readable text to transmit data objects consisting of attribute–value pairs. It is the primary data format used for asynchronous browser/server communication (AJAJ), largely replacing XML (used by AJAX).> Although originally derived from the JavaScript scripting language, JSON is a language-independent data format. Code for parsing and generating JSON data is readily available in many programming languages.> The JSON format was originally specified by Douglas Crockford. It is currently described by two competing standards, RFC 7159 and ECMA-404. The ECMA standard is minimal, describing only the allowed grammar syntax, whereas the RFC also provides some semantic and security considerations. The official Internet media type for JSON is application/json. The JSON filename extension is .json.> — Wikipedia#### General Learning:

References/Docs:

Standards/Specifications:

Architecting:

3.17 - Learn JS Templates

A JavaScript template is typically used, but not always with a MV* solution to separate parts of the view (i.e., the UI) from the logic and model (i.e., the data or JSON).

Note that JavaScript 2015 (aka ES6) added a native templating mechanism called ["Templates strings"](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/template_strings ""Templates strings""). Additionally, templating as of late has been replaced by things like JSX, a template element, or HTML strings.

If I was not using React & JSX I'd first reach for JavaScript ["Templates strings"](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/template_strings ""Templates strings"") and when that was lacking move to nunjucks.

3.18 - Learn Static Site Generators

Static site generators, typically written using server side code (i.e., ruby, php, python, nodeJS, etc.), produce static HTML files from static text/data + templates that are intended to be sent from a server to the client statically without a dynamic nature.

General Learning:

3.19 - Learn Computer Science via JS

3.20 - Learn Front-End Application Architecture

General Learning:

Deprecated Learning Materials:

Not a lot of general content is being created on this topic as of late. Most of the content offered for learning how to build front-end/SPA/JavaScript applications presupposes you've decided up a tool like Angular, Ember, React, or Aurelia.

My advice, in 2019 learn React and Mobx and Apollo/graphql.

3.21 - Learn Data (i.e. JSON) API Design

3.22 - Learn React

Learning React:

Mastering React:

Once you have a good handle on React move on to learning a more robust state management solution like MobX. If you are an experienced developer with Functional Programming knowledge look at Redux. If you need help understanding the role of state management beyond React's setState watch, "Advanced State Management in React (feat. Redux and MobX)".

3.23 - Learn Application State Management

3.24 - Learn Progressive Web App

Unlike traditional applications, progressive web apps are a hybrid of regular web pages (or websites) and a mobile application. This new application model attempts to combine features offered by most modern browsers with the benefits of mobile experience.> In 2015, designer Frances Berriman and Google Chrome engineer Alex Russell coined the term "Progressive Web Apps" to describe apps taking advantage of new features supported by modern browsers, including Service Workers and Web App Manifests, that let users upgrade web apps to be first-class applications in their native OS.> According to Google Developers, these characteristics are:* Progressive - Work for every user, regardless of browser choice because they’re built with progressive enhancement as a core tenet.

  • Responsive - Fit any form factor: desktop, mobile, tablet, or forms yet to emerge.
  • Connectivity independent - Service workers allow work offline, or on low quality networks.
  • App-like - Feel like an app to the user with app-style interactions and navigation.
  • Fresh - Always up-to-date thanks to the service worker update process.
  • Safe - Served via HTTPS to prevent snooping and ensure content hasn’t been tampered with.
  • Discoverable - Are identifiable as “applications” thanks to W3C manifests[6] and service worker registration scope allowing search engines to find them.
  • Re-engageable - Make re-engagement easy through features like push notifications.
  • Installable - Allow users to “keep” apps they find most useful on their home screen without the hassle of an app store.
  • Linkable - Easily shared via a URL and do not require complex installation.

Wikipedia* A Beginner’s Guide To Progressive Web Apps [read]

3.25 - Learn JS API Design

3.26 - Learn Browser Web Developer Tools

Web development tools allow web developers to test and debug their code. They are different from website builders and IDEs in that they do not assist in the direct creation of a webpage, rather they are tools used for testing the user facing interface of a website or web application.> Web development tools come as browser add-ons or built in features in web browsers. The most popular web browsers today like, Google Chrome, Firefox, Opera, Internet Explorer, and Safari have built in tools to help web developers, and many additional add-ons can be found in their respective plugin download centers.> Web development tools allow developers to work with a variety of web technologies, including HTML, CSS, the DOM, JavaScript, and other components that are handled by the web browser. Due to the increasing demand from web browsers to do more popular web browsers have included more features geared for developers.> — Wikipedia
While most browsers come equipped with web developer tools, the Chrome developer tools are currently the most talked about and widely used.

I'd suggest learning and using the Chrome web developer tools, simply because the best resources for learning web developer tools revolves around Chrome DevTools.

Learn Chrome Web Developer Tools:

Chrome Web Developer Tools Docs:

3.27 - Learn the Command Line (aka CLI)

A command-line interface or command language interpreter (CLI), also known as command-line user interface, console user interface, and character user interface (CUI), is a means of interacting with a computer program where the user (or client) issues commands to the program in the form of successive lines of text (command lines).> — Wikipedia#### General Learning:

Mastering:

3.28 - Learn Node.js

Node.js is an open-source, cross-platform runtime environment for developing server-side web applications. Node.js applications are written in JavaScript and can be run within the Node.js runtime on OS X, Microsoft Windows, Linux, FreeBSD, NonStop, IBM AIX, IBM System z and IBM i. Its work is hosted and supported by the Node.js Foundation, a collaborative project at Linux Foundation.> Node.js provides an event-driven architecture and a non-blocking I/O API designed to optimize an application's throughput and scalability for real-time web applications. It uses Google V8 JavaScript engine to execute code, and a large percentage of the basic modules are written in JavaScript. Node.js contains a built-in library to allow applications to act as a web server without software such as Apache HTTP Server, Nginx or IIS.> — Wikipedia#### General Learning:

3.29 - Learn Modules

General Learning:

References/Docs:

3.30 - Learn Module loaders/bundlers

Webpack:

Rollup:

3.31 - Learn Package Manager

A package manager or package management system is a collection of software tools that automates the process of installing, upgrading, configuring, and removing software packages for a computer's operating system in a consistent manner. It typically maintains a database of software dependencies and version information to prevent software mismatches and missing prerequisites.> — Wikipedia#### General Learning:

3.32 - Learn Version Control

A component of software configuration management, version control, also known as revision control or source control, is the management of changes to documents, computer programs, large web sites, and other collections of information. Changes are usually identified by a number or letter code, termed the "revision number," "revision level," or simply "revision." For example, an initial set of files is "revision 1." When the first change is made, the resulting set is "revision 2," and so on. Each revision is associated with a timestamp and the person making the change. Revisions can be compared, restored, and with some types of files, merged.> — Wikipedia
The most common solution used for version control today is Git. Learn it!

General Learning:

Mastering:

References/Docs:

3.33 - Learn Build and Task Automation

Build automation is the process of automating the creation of a software build and the associated processes including: compiling computer source code into binary code, packaging binary code, and running automated tests.> — Wikipedia#### General Learning:

References/Docs:

Gulp is great. However, you might only need npm run. Before turning to additional complexity in your application stack ask yourself if npm run can do the job. If you need more, use Gulp.

Read:

3.34 - Learn Site Performance Optimization

Web performance optimization, WPO, or website optimization is the field of knowledge about increasing the speed in which web pages are downloaded and displayed on the user's web browser. With the average internet speed increasing globally, it is fitting for website administrators and webmasters to consider the time it takes for websites to render for the visitor.> — Wikipedia#### General Learning:

3.35 - Learn Testing

Unit Testing - In computer programming, unit testing is a software testing method by which individual units of source code, sets of one or more computer program modules together with associated control data, usage procedures, and operating procedures, are tested to determine whether they are fit for use. Intuitively, one can view a unit as the smallest testable part of an application.> — Wikipedia> Functional Testing - Functional testing is a quality assurance (QA) process and a type of black box testing that bases its test cases on the specifications of the software component under test. Functions are tested by feeding them input and examining the output, and internal program structure is rarely considered (not like in white-box testing). Functional testing usually describes what the system does.> — Wikipedia> Integration Testing - Integration testing (sometimes called integration and testing, abbreviated I&T) is the phase in software testing in which individual software modules are combined and tested as a group. It occurs after unit testing and before validation testing. Integration testing takes as its input modules that have been unit tested, groups them in larger aggregates, applies tests defined in an integration test plan to those aggregates, and delivers as its output the integrated system ready for system testing.> — Wikipedia#### General Learning:

3.36 - Learn Headless Browsers

A headless browser is a web browser without a graphical user interface.> Headless browsers provide automated control of a web page in an environment similar to popular web browsers, but are executed via a command line interface or using network communication. They are particularly useful for testing web pages as they are able to render and understand HTML the same way a browser would, including styling elements such as page layout, color, font selection and execution of JavaScript and AJAX which are usually not available when using other testing methods. Google stated in 2009 that using a headless browser could help their search engine index content from websites that use AJAX.> — Wikipedia* Getting Started with Headless Chrome [readme]

PhantomJS is no longer maintained, Headless Chrome steps in.

3.37 - Learn Offline Development

Offline development (aka offline first) is an area of knowledge and discussion around development practices for devices that are not always connected to the Internet or a power source.

General Learning:

3.38 - Learn Web/Browser/App Security

3.39 - Learn Multi-Device Development

Image source: http://bradfrost.com/blog/post/this-is-the-web/

A website or web application can run on a wide range of computers, laptops, tablets and phones, as well as a handful of new devices (watches, thermostats, fridges, etc.). How you determine what devices you'll support and how you will develop to support those devices is called, "multi-device development strategy". Below, I list the most common multi-device development strategies.

  • Build a responsive (RWD) web site/app for all devices.
  • Build an adaptive/progressively enhanced web site/app for all devices.
  • Build a website, web app, native app, or hybrid-native app for each individual device or a grouping of devices.
  • Attempt to retrofit something you have already built using bits and parts from strategies 1, 2 or 3.

General Learning:

Chapter 4. Learning Front-end Dev: Instructor Directed Resources/Recommendations

This chapter highlights a few options for instructor directed learning via front-end development schools, courses, programs, and bootcamps.

The table below contains a small selection of instructor-led courses (i.e. programs, schools, and bootcamps). Use the table to get a general idea of what is available, the cost, duration, and locations of courses. (Be aware the information can change quickly)

company program price estimate on site remote duration Betamore Front-end Web Development 3,000 Baltimore, MD 10 weeks BLOC Become a Front-end Developer 4,999 yes 16 weeks @ 25hr/wk or 32 weeks @ 10hr/wk General Assembly Front-end Web Development 3,500 multiple locations 3 hrs/day 2 days/wk for 8 weeks Thinkful Front-end Web Development 300 per month yes 15 hrs/wk for 3 months Turing School of Software & Design Front-End Engineering 20,000 Denver, CO 7 months full time Notes:

  1. For a complete list of schools, courses, programs, and bootcamps to evaluate have a look at switchup.org or coursereport.com.

If you can't afford a directed education (can be very expensive), a self directed education using screencasts, books, and articles is a viable alternative to learn front-end development for the self-driven individual.

Chapter 5. Front-end Dev Tools

This chapter identifies the tools of the trade. Make sure you understanding the category that a set of tools falls within, before studying the tools themselves. Note that just because a tool is listed, or a category of tools is documented, this does not equate to an assertion on my part that a front-end developer should learn it and use it. Choose your own toolbox. I'm just providing the common toolbox options.

5.1 - Doc/API Browsing Tools

Tools to browse common developer documents and developer API references.

Cheatsheets:

5.2 - SEO Tools

General SEO Tools:

Tools for Finding SEO Tools:

5.3 - Prototyping & Wireframing Tools

Creating:

Collaboration / Presenting:

5.4 - Diagramming Tools

5.5 - HTTP/Network Tools

5.6 - Code Editing Tools

A source code editor is a text editor program designed specifically for editing source code of computer programs by programmers. It may be a standalone application or it may be built into an integrated development environment (IDE) or web browser. Source code editors are the most fundamental programming tool, as the fundamental job of programmers is to write and edit source code.> — Wikipedia
Front-end code can minimally be edited with a simple text editing application like Notepad or TextEdit. But, most front-end practitioners use a code editor specifically design for editing a programming language.

Code editors come in all sorts of types and size, so to speak. Selecting one is a rather subjective engagement. Choose one, learn it inside and out, then get on to learning HTML, CSS, DOM, and JavaScript.

However, I do strongly believe, minimally, a code editor should have the following qualities (by default or by way of plugins):

  1. Good documentation on how to use the editor
  2. Report (i.e., hinting/linting/errors) on the code quality of HTML, CSS, and JavaScript.
  3. Offer syntax highlighting for HTML, CSS, and JavaScript.
  4. Offer code completion for HTML, CSS, and JavaScript.
  5. Be customizable by way of a plug-in architecture
  6. Have available a large repository of third-party/community plug-ins that can be used to customize the editor to your liking
  7. Be small, simple, and not coupled to the code (i.e., not required to edit the code)

Code Editors:

Online Code Editors:

Shareable & Runnable Simple Code Editors:

Used to share limited amounts of immediately runnable code. Not a true code editor but a tool that can be used to share small amounts of immediately runnable code in a web browser.

I recommending using Visual Studio Code because of the quality of the tool and the continuous improvements made to the editor that likely won't stop or slow due to the fact that Microsoft is behind the tool. It is widely used:

Image source: https://2018.stateofjs.com/other-tools/text_editors

5.7 - Browser Tools

JS Utilities to fix Browsers:

General Reference Tools to Determine If X Browser Supports X:

Browser Development/Debug Tools:

Chrome Developer Tools (aka DevTools)Per-Panel DocumentationCommand Line API ReferenceKeyboard & UI Shortcuts ReferenceSettings* Firefox Developer Tools

JavaScript Utilities to Determine If X Browser Supports X:

Broad Browser Polyfills/Shims:

Hosted Testing/Automation for Browsers:

Headless Browsers:

Browser Automation:

Used for functional testing and monkey testing.

Browser Hacks:

Browser Syncing Tools:

Browser List:

Share target browsers between different front-end tools, like Autoprefixer, Stylelint and babel-preset-env.
Browserslisthttp://browserl.ist/### 5.8 - HTML Tools

HTML Templates/Boilerplates/Starter Kits:

HTML Polyfill:

Transpiling:

References:

Linting/Hinting:

Optimizer:

Online Creation/Generation/Experimentation Tools:

Authoring Conventions:

Workflow:

HTML Outliner:

Trending HTML Repositories on GitHub This Month:

https://github.com/trending?l=html&since=monthly

5.9 - CSS Tools

CSS Utilities:

CSS Frameworks (utilities + UI):

Mobile Only CSS Frameworks:

CSS Reset:

A CSS Reset (or “Reset CSS”) is a short, often compressed (minified) set of CSS rules that resets the styling of all HTML elements to a consistent baseline.> — cssreset.com* Eric Meyer's “Reset CSS” 2.0

Transpiling:

References:

Linting/Hinting:

Code Formatter/Beautifier:

Optimizer:

Online Creation/Generation/Experimentation Tools:

Architecting CSS:

Authoring/Architecting Conventions:

Style Guide Resources:

CSS in JS:

Trending CSS Repositories on GitHub This Month:

https://github.com/trending?l=css&since=monthly

5.10 - DOM Tools

DOM Libraries/Frameworks:

DOM Utilities:

DOM Event Tools:

DOM Performance Tools:

References:

DOM Polyfills/Shims:

Virtual DOM:

5.11 - JavaScript Tools

JS Utilities:

Transforming JavaScript Objects Tool:

Transpiling / Type Checking (ES to ES):

Type Checking (ES to ES):

Transpiling (ES to ES):

Code-analysis Engine:

Linting/Hinting & Style Linter:

Unit Testing:

Testing Assertions for Unit Testing:

Test Spies, Stubs, and Mocks for Unit Testing:

Code Formater/Beautifier:

Performance Testing:

Visualization, Static Analysis, Complexity, Coverage Tools:

Optimizer:

Obfuscate:

Sharable/Runnable Code Editors:

Online Regular Expression Editors/Visual Tools:

Authoring Convention Tools:

Trending JS Repositories on GitHub This Month:

https://github.com/trending?l=javascript&since=monthly

Most Depended upon Packages on NPM:

https://www.npmjs.com/browse/depended

5.12 - Headless CMS Tools

Site Generator Listings:

5.13 - Static Site Generators Tools

Site Generator Listings:

5.14 - Accessibility Tools

Guides

Site Scanners

Color Contrast Testers

Low-Vision Simulators

Screen Readers

Readability Testers

Articles

5.15 - App Frameworks (Desktop, Mobile, Tablet, etc.) Tools

Front-End App Frameworks:

Native Hybrid Mobile WebView (i.e., Browser Engine Driven) Frameworks:

These solutions typically use Cordova, crosswalk, or a custom WebView as a bridge to native APIs.

Native Hybrid Mobile Development Webview (i.e., Browser Engine Driven) Environments/Platforms/Tools:

These solutions typically use Cordova, crosswalk, or a custom WebView as a bridge to native APIs.

Native Desktop App Frameworks:

Native Mobile App Frameworks (Aka JavaScript Native Apps)

These solutions use a JS engine at runtime to interpret JS and bridge that to native APIs. No browser engine or WebView is used. The UI is constructed from native UI components.

References & demo apps:

Performance:

If you are new to front-end/JavaScript application development I'd start with Vue.js. Then I'd work my way to React. Then I'd look at Angular 2+, Ember, or Aurelia.

If you are building a simple website that has minimal interactions with data (i.e. mostly a static content web site), you should avoid a front-end framework. A lot of work can be done with a task runner like Gulp and jQuery, while avoiding the unnecessary complexity of learning and using an app framework tool.

Want something smaller than React, consider Preact. Preact is an attempt to recreate the core value proposition of React (or similar libraries like Mithril) using as little code as possible, with first-class support for ES2015. Currently the library is around 3kb (minified & gzipped).

5.16 - JavaScript App Manager

5.17 - State Tools

5.18 - Progressive Web App Tools:

5.19 - GUI Development/Build Tools

5.20 - Templating/Data Binding Tools

Just Templating:

Templating and Reactive Data Binding:

Templating to Virtual DOM:

5.21 - UI Widget & Component Toolkits

On Web Platform:

React Specific, On Web Platform:

Native Desktop/Laptop/Netbook Apps via Web Platform (i.e. used with NW.js and Electron):

If you need a basic set of UI Widgets/Components start with Semantic UI. If you are building something that needs a grid, spreadsheet, or pivot grid you'll have to look at Kendo UI or Webix. Keep in mind that most of these solutions still require jQuery.

5.22 - Data Visualization (e.g., Charts) Tools

JS Libraries:

Widgets & Components:

Services (i.e. hosted data visualization services for embedding and sharing):

5.23 - Graphics (e.g., SVG, canvas, webgl) Tools

General:

Canvas:

SVG:

WebGL:

5.24 - Animation Tools

CSS and JavaScript Utilities:

Polyfills/Shims:

Animation References:

5.25 - JSON Tools

Online Editors:

Formatter & Validator:

Query Tools:

Generating Mock JSON Tools:

Online JSON Mocking API Tools:

List of public JSON API's:

Local JSON Mocking API Tools:

JSON Specifications/Schemas:

5.26 - Placeholder Content Tools

Images:

Device Mockups:

Text:

User Data:

5.27 - Testing Tools

Software Testing Frameworks:

Testing Assertions for Unit Testing:

Test Spies, Stubs, and Mocks for Unit Testing:

Hosted Testing/Automation for Browsers:

Integration/Functional Testing:

Browser Automation:

UI Testing Tools:

Automated dead link and error detectors:

HTTP Stubbing

5.28 - Front-End Data Storage Tools (i.e. Data storage solution in the client)

5.29 - Module Loading/Bundling Tools

5.30 - Module/Package Repository Tools

5.31 - Hosting Tools

General

Static

5.32 - Project Management & Code Hosting Tools

5.33 - Collaboration & Communication Tools

Code/GitHub Collaboration & Communication:

5.34 - Content Management Hosted/API Tools

Headless CMS Tools:

Self-hosted Headless CMS Tools:

Hosted CMS:

Static CMS Tools:

5.35 - Back-end/API tools

Data/back-end as a service aka BAAS:

Data/back-end

GraphQLApolloRelay* Falcor

User Management as a Service:

Search

5.36 - Offline Tools

For more tools look here.

5.37 - Security Tools

Coding Tool:

Security Scanners/Evaluators/Testers:

References:

5.38 - Tasking (aka Build) Tools

Tasking/Build Tools:

Opinionated Tasking/Build pipeline tools:

Before reaching for Gulp make sure npm scripts or yarn script won't fit the bill. Read, ["Why I Left Gulp and Grunt for npm Scripts"](https://medium.freecodecamp.com/why-i-left-gulp-and-grunt-for-npm-scripts-3d6853dd22b8#.nw3huib54 ""Why I Left Gulp and Grunt for npm Scripts"").

5.39 - Deployment Tools

5.40 - Site/App Monitoring Tools

Uptime Monitoring:

General Monitoring Tools:

5.41 - JavaScript Error Reporting/Monitoring

5.42 - Performance Tools

Reporting:

JS Tools:

Budgeting:

References/Docs:

Checklist:

5.43 - Tools for Finding Tools

5.44 - Documentation Generation Tools

Chapter 6. Front-end Communities, Newsletters, News Sites, & Podcasts

General Front-End Newsletters, News, & Podcasts:

HTML/CSS Newsletters:

JavaScript Newsletters, News, & Podcasts:

Front-End Communities

Notes:

  1. Need more Newsletters, News Sites, & Podcasts look at Awesome Newsletter.
  2. Find local front-end development communities by searching https://www.meetup.com/

Angular 8 Tutorial By Example: (REST API, HttpClient GET, Components, Services & ngFor)

Angular 8 Tutorial By Example: (REST API, HttpClient GET, Components, Services & ngFor)

Angular 8 Tutorial By Example: (REST API, HttpClient GET, Components, Services & ngFor) - In this tutorial, you'll learn by example how to send GET requests to REST API servers in your Angular 8 application using HttpClient...

Angular 8 Tutorial By Example: (REST API, HttpClient GET, Components, Services & ngFor) - In this tutorial, you'll learn by example how to send GET requests to REST API servers in your Angular 8 application using HttpClient...

We’ll also learn how to use the basic concepts of Angular like components and services and how to use the ngFor directive to display collections of data.

We’ll be consuming a JSON API available from NewsAPI.org

Throughout this tutorial, we are going to build a simple example from scratch using Angular CLI 8 and we’ll see how to use HttpClient to send GET requests to third-party REST API servers and how to consume and display the returned JSON data.

In more details, we'll learn:

  • How to create an Angular 8 project using Angular CLI,
  • How to quickly set up routing in our project,
  • How to create Angular components and services,
  • How to subscribe to Observables,
  • How to use the ngFor directive in templates to iterate over data.

You can also follow this tutorial as a video:

Prerequisites

Before getting started, you need a few requirements. You need to have the following tools installed on your development machine:

  • Node.js and npm. You can install both of them from the official website.
  • Angular CLI 8 (You can install it from npm using: npm install -g @angular/cli)
Creating an Angular 8 Project

Now let’s create our Angular 8 project. Open a new terminal and run the following command:

$ ng new angular-httpclient-demo

The CLI will prompt you if Would you like to add Angular routing? (y/N), type y. And Which stylesheet format would you like to use? Choose CSS and type Enter.

Next, you can serve your application locally using the following commands:

$ cd ./angular-httpclient-demo
$ ng serve

Your application will be running from <a href="http://localhost:4200" target="_blank">http://localhost:4200</a>.

Getting News Data

Before you can fetch the news data from NewsAPI.org which offers a free plan for open source and development projects, you first need to go the register page for getting an API key.

Adding an Angular Service

Next, let’s create a service that will take care of getting data from the news API. Open a new terminal and run the following command:

$ ng generate service api

Setting up HttpClient

Next, open the src/app/app.module.ts file then import HttpClientModule and add it to the importsarray:

// [...]
import { HttpClientModule } from '@angular/common/http';

@NgModule({
  declarations: [AppComponent],
  entryComponents: [],
  imports: [
    // [...]
    HttpClientModule,
  ],
  // [...]
})
export class AppModule {}

That's all, we are now ready to use the HttpClient in our project.

Injecting HttpClient in The Angular Service

Next, open the src/app/api.service.ts file and inject HttpClient via the service constructor:

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';

@Injectable({
  providedIn: 'root'
})
export class ApiService {

  constructor(private httpClient: HttpClient) { }
}

Sending GET Request for Fetching Data

Next, define an API_KEY variable which will hold your API key from the News API:

export class ApiService {
  API_KEY = 'YOUR_API_KEY';

Finally, add a method that sends a GET request to an endpoint for TechCrunch news:

  public getNews(){
    return this.httpClient.get(`https://newsapi.org/v2/top-headlines?sources=techcrunch&apiKey=${this.API_KEY}`);
  }

That’s all we need to add for the service.

How the <strong>HttpClient.get()</strong> Method Works

The HttpClient get() method is designed to send HTTP GET requests. The syntax is as follows:

get(url: string, options: {
      headers?: HttpHeaders;
      observe: 'response';
      params?: HttpParams;
      reportProgress?: boolean;
      responseType?: 'json';
      withCredentials?: boolean;
}): Observable<HttpResponse<Object>>;

It takes a REST API endpoint and an optional options object and returns an Observable instance.

Creating an Angular 8 Component

Now, let's create an Angular 8 component for displaying the news data. Head back to your terminal and run the following command:

$ ng generate component news

Injecting ApiService in Your Component

Next, open the src/app/news/news.component.ts file and start by importing ApiService in your component:

import { ApiService } from '../api.service';

Next, you need to inject ApiService via the component's constructor:

import { Component, OnInit } from '@angular/core';
import { ApiService } from '../api.service';
@Component({
  selector: 'app-news',
  templateUrl: './news.component.html',
  styleUrls: ['./news.component.css']
})
export class NewsComponent implements OnInit {

  constructor(private apiService: ApiService) { }
}

Sending the GET Request & Subscribing to The Observable

Next, define an articles variable and call the getNews() method of the API service in the ngOnInit()method of the component:

export class NewsComponent implements OnInit {
  articles;

  constructor(private apiService: ApiService) { }
  ngOnInit() {
    this.apiService.getNews().subscribe((data)=>{
      console.log(data);
      this.articles = data['articles'];
    });
  }
}

This will make sure our data is fetched once the component is loaded.

We call the getNews() method and subscribe to the returned Observable which will send a GET request to the news endpoint.

Displaying Data in The Template with NgFor

Let’s now display the news articles in our component template. Open the src/app/news.component.htmlfile and update it as follows:

<div *ngFor="let article of articles">
  <h2>{{article.title}}</h2>

    <p>
      {{article.description}}
    </p>
    <a href="{{article.url}}">Read full article</a>
</div>

Adding the Angular Component to The Router

Angular CLI 8 has automatically added routing for us, so we don’t need to set up anything besides adding the component(s) to our Router configuration. Open the src/app/app-routing.module.ts file and start by importing the news component as follows:

import { NewsComponent } from './news/news.component';

Next, add the component to the routes array:

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { NewsComponent } from './news/news.component';
const routes: Routes = [
  {path:'news', component: NewsComponent}
];
@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})
export class AppRoutingModule { }

You can now access your component from the /news path.

Conclusion

In this tutorial, we used Angular 8 to build a simple news application that retrieves data from a JSON REST API using the get() method of HttpClient. We’ve seen how to subscribe to the RxJS Observable returned by the get() method and how to use the *ngFor directive to iterate over fetched data in the template. Finally, we’ve seen how we can create an Angular 8 project using Angular CLI v8, how to generate components and services and how to configure routing for the component.

Angular 7 CRUD with Nodejs and MySQL Example

Angular 7 CRUD with Nodejs and MySQL Example

Angular7 CRUD with nodejs and mysql example - Hey there, Today we will proceed to create a demo for CRUD with Mysql, Express, Angular7(MEAN) and Nodejs from scratch using Angular CLI

Below are the requirements for creating the CRUD on MEAN

  • Node.js
  • Angular CLI
  • Angular 7
  • Mysql
  • IDE or Text Editor

We assume that you have already available the above tools/frameworks and you are familiar with all the above that what individually actually does.

So now we will proceed step by step to achieve the task.

1. Update Angular CLI and Create Angular 7 Application

At first, We have to update the Angular CLI to the latest version. Open the terminal then go to the project folder and then type the below command to update the Angular CLI

sudo npm install -g @angular/cli

Once the above task finishes, Next task is to create new angular application with below command. So go to your project folder and then type below command:

ng new angular7-crud

then go to the newly created folder of angular application with cd /angular7-crud  and type **ng serve. **Now, open the browser then go to http://localhost:4200 you should see this page.

Angular 7 CRUD with Nodejs and MySQL Example

2. Create a server with node.js express and Mysql for REST APIs

create a separate folder named server for server-side stuff, Then move inside folder and create server.js by typing touch server.js

Let’s have a look on the server.js file

let app = require('express')(),
server = require('http').Server(app),
bodyParser = require('body-parser')
express = require('express'),
cors = require('cors'),
http = require('http'),
path = require('path');
 
let articleRoute = require('./Routes/article'),
util = require('./Utilities/util');
 
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: false }));
 
app.use(cors());
 
app.use(function(err, req, res, next) {
return res.send({ "statusCode": util.statusCode.ONE, "statusMessage": util.statusMessage.SOMETHING_WENT_WRONG });
});
 
app.use('/article', articleRoute);
 
// catch 404 and forward to error handler
app.use(function(req, res, next) {
next();
});
 
/*first API to check if server is running*/
app.get('*', (req, res) => {
res.sendFile(path.join(__dirname, '../server/client/dist/index.html'));
})
 
 
server.listen(3000,function(){
console.log('app listening on port: 3000');
});

In the above file we can see, at the top, there are required packages for the app. Below that body parsing, middleware and routing is done.

The next task is to create routes and create a file article.js . So creating a folder name ‘Routes’ and adding article.js within it.

Add the below code for routing in article.js inside routing folder

let express = require('express'),
router = express.Router(),
util = require('../Utilities/util'),
articleService = require('../Services/article');
 
/**Api to create article */
router.post('/create-article', (req, res) => {
articleService.createArticle(req.body, (data) => {
res.send(data);
});
});
 
// /**Api to update article */
router.put('/update-article', (req, res) => {
articleService.updateArticle(req.body, (data) => {
res.send(data);
});
});
 
// /**Api to delete the article */
router.delete('/delete-article', (req, res) => {
articleService.deleteArticle(req.query, (data) => {
res.send(data);
});
});
 
/**Api to get the list of article */
router.get('/get-article', (req, res) => {
documentService.getArticle(req.query, (data) => {
res.send(data);
});
});
 
// /**API to get the article by id... */
router.get('/get-article-by-id', (req, res) => {
articleService.getArticleById(req.query, (data) => {
res.send(data);
});
});
 
module.exports = router;

Now create a folder named Utilities for all config, common methods and mysql connection config.

Now I am adding config values in a file named config.js

let environment = "dev";
 
let serverURLs = {
"dev": {
"NODE_SERVER": "http://localhost",
"NODE_SERVER_PORT": "3000",
"MYSQL_HOST": 'localhost',
"MYSQL_USER": 'root',
"MYSQL_PASSWORD": 'password',
'MYSQL_DATABASE': 'demo_angular7_crud',
}
}
 
let config = {
"DB_URL_MYSQL": {
"host": `${serverURLs[environment].MYSQL_HOST}`,
"user": `${serverURLs[environment].MYSQL_USER}`,
"password": `${serverURLs[environment].MYSQL_PASSWORD}`,
"database": `${serverURLs[environment].MYSQL_DATABASE}`
},
"NODE_SERVER_PORT": {
"port": `${serverURLs[environment].NODE_SERVER_PORT}`
},
"NODE_SERVER_URL": {
"url": `${serverURLs[environment].NODE_SERVER}`
}
};
 
module.exports = {
config: config
};

Now configure mysql connection. So I am writing the connection with database in a separate file. So creating a file named mysqkConfig.js under Utilities folder and adding the below line of code for mysql connection:

var config = require("../Utilities/config").config;
var mysql = require('mysql');
var connection = mysql.createConnection({
host: config.DB_URL_MYSQL.host,
user: config.DB_URL_MYSQL.user,
password: config.DB_URL_MYSQL.password,
database: config.DB_URL_MYSQL.database,
});
 
connection.connect(() => {
require('../Models/Article').initialize();
});
 
let getDB = () => {
return connection;
}
 
module.exports = {
getDB: getDB
}

Now I am creating separate file name util.js to save common methods and common status code/message:

// Define Error Codes
let statusCode = {
OK: 200,
FOUR_ZERO_FOUR: 404,
FOUR_ZERO_THREE: 403,
FOUR_ZERO_ONE: 401,
FIVE_ZERO_ZERO: 500
};
 
// Define Error Messages
let statusMessage = {
SERVER_BUSY : 'Our Servers are busy. Please try again later.',
DATA_UPDATED: 'Data updated successfully.',
DELETE_DATA : 'Delete data successfully',
 
};
 
module.exports = {
statusCode: statusCode,
statusMessage: statusMessage
}

Now the next part is model, So create a folder named Models and create a file **Article.js **and add the below code in it:

let mysqlConfig = require("../Utilities/mysqlConfig");
 
let initialize = () => {
mysqlConfig.getDB().query("create table IF NOT EXISTS article (id INT auto_increment primary key, category VARCHAR(30), title VARCHAR(24))");
 
}
 
module.exports = {
initialize: initialize
}

Now create DAO folder and add a file articleDAO.js for writting the mysql queries common functions:

let dbConfig = require("../Utilities/mysqlConfig");


 
let getArticle = (criteria, callback) => {
//criteria.aricle_id ? conditions += ` and aricle_id = '${criteria.aricle_id}'` : true;
dbConfig.getDB().query(`select * from article where 1`,criteria, callback);
}
 
let getArticleDetail = (criteria, callback) => {
    let conditions = "";
criteria.id ? conditions += ` and id = '${criteria.id}'` : true;
dbConfig.getDB().query(`select * from article where 1 ${conditions}`, callback);
}
 
let createArticle = (dataToSet, callback) => {
console.log("insert into article set ? ", dataToSet,'pankaj')
dbConfig.getDB().query("insert into article set ? ", dataToSet, callback);
}
 
let deleteArticle = (criteria, callback) => {
let conditions = "";
criteria.id ? conditions += ` and id = '${criteria.id}'` : true;
console.log(`delete from article where 1 ${conditions}`);
dbConfig.getDB().query(`delete from article where 1 ${conditions}`, callback);
 
}
 
let updateArticle = (criteria,dataToSet,callback) => {
    let conditions = "";
let setData = "";
criteria.id ? conditions += ` and id = '${criteria.id}'` : true;
dataToSet.category ? setData += `category = '${dataToSet.category}'` : true;
dataToSet.title ? setData += `, title = '${dataToSet.title}'` : true;
console.log(`UPDATE article SET ${setData} where 1 ${conditions}`);
dbConfig.getDB().query(`UPDATE article SET ${setData} where 1 ${conditions}`, callback);
}
module.exports = {
getArticle : getArticle,
createArticle : createArticle,
deleteArticle : deleteArticle,
updateArticle : updateArticle,
getArticleDetail : getArticleDetail
}

Now one create Services folder and add a file article.js for all the logic of API

let async = require('async'),
parseString = require('xml2js').parseString;
 
let util = require('../Utilities/util'),
articleDAO = require('../DAO/articleDAO');
//config = require("../Utilities/config").config;
 
 
/**API to create the atricle */
let createArticle = (data, callback) => {
async.auto({
article: (cb) => {
var dataToSet = {
"category":data.category?data.category:'',
"title":data.title,
}
console.log(dataToSet);
articleDAO.createArticle(dataToSet, (err, dbData) => {
if (err) {
cb(null, { "statusCode": util.statusCode.FOUR_ZERO_ONE, "statusMessage": util.statusMessage.SERVER_BUSY });
return;
}
 
cb(null, { "statusCode": util.statusCode.OK, "statusMessage": util.statusMessage.DATA_UPDATED,"result":dataToSet });
});
}
//]
}, (err, response) => {
callback(response.article);
});
}
 
/**API to update the article */
let updateArticle = (data,callback) => {
async.auto({
articleUpdate :(cb) =>{
if (!data.id) {
cb(null, { "statusCode": util.statusCode.FOUR_ZERO_ONE, "statusMessage": util.statusMessage.PARAMS_MISSING })
return;
}
console.log('phase 1');
var criteria = {
id : data.id,
}
var dataToSet={
"category": data.category,
"title":data.title,
}
console.log(criteria,'test',dataToSet);
                    articleDAO.updateArticle(criteria, dataToSet, (err, dbData)=>{
                        if(err){
cb(null,{"statusCode":util.statusCode.FOUR_ZERO_ONE,"statusMessage":util.statusMessage.SERVER_BUSY});
                        return; 
                        }
                        else{
cb(null, { "statusCode": util.statusCode.OK, "statusMessage": util.statusMessage.DATA_UPDATED,"result":dataToSet });                        
                        }
                    });
}
}, (err,response) => {
callback(response.articleUpdate);
});
}
 
/**API to delete the subject */
let deleteArticle = (data,callback) => {
console.log(data,'data to set')
async.auto({
removeArticle :(cb) =>{
if (!data.id) {
cb(null, { "statusCode": util.statusCode.FOUR_ZERO_ONE, "statusMessage": util.statusMessage.PARAMS_MISSING })
return;
}
var criteria = {
id : data.id,
}
articleDAO.deleteArticle(criteria,(err,dbData) => {
if (err) {
console.log(err);
cb(null, { "statusCode": util.statusCode.FOUR_ZERO_ONE, "statusMessage": util.statusMessage.SERVER_BUSY });
return;
}
cb(null, { "statusCode": util.statusCode.OK, "statusMessage": util.statusMessage.DELETE_DATA });
});
}
}, (err,response) => {
callback(response.removeArticle);
});
}
 
/***API to get the article list */
let getArticle = (data, callback) => {
async.auto({
article: (cb) => {
articleDAO.getArticle({},(err, data) => {
if (err) {
cb(null, {"errorCode": util.statusCode.INTERNAL_SERVER_ERROR,"statusMessage": util.statusMessage.SERVER_BUSY});
return;
}
cb(null, data);
return;
});
}
}, (err, response) => {
callback(response.article);
})
}
 
/***API to get the article detail by id */
let getArticleById = (data, callback) => {
async.auto({
article: (cb) => {
let criteria = {
"id":data.id
}
articleDAO.getArticleDetail(criteria,(err, data) => {
if (err) {
console.log(err,'error----');
cb(null, {"errorCode": util.statusCode.INTERNAL_SERVER_ERROR,"statusMessage": util.statusMessage.SERVER_BUSY});
return;
}
cb(null, data[0]);
return;
});
}
}, (err, response) => {
callback(response.article);
})
}
 
module.exports = {
createArticle : createArticle,
updateArticle : updateArticle,
deleteArticle : deleteArticle,
getArticle : getArticle,
getArticleById : getArticleById
};

3. Create angular component for performing CRUD task of article

ng g component article

Above command will generate all required files for build article component and also automatically added this component to app.module.ts.

create src/app/article/article.component.css (0 bytes)
create src/app/article/article.component.html (23 bytes)
create src/app/article/article.component.spec.ts (614 bytes)
create src/app/article/article.component.ts (321 bytes)
update src/app/app.module.ts (390 bytes)

Now we need to add HttpClientModule to app.module.ts. Open and edit src/app/app.module.ts then add this import. And add it to @NgModule imports after BrowserModule. Now our app.module.ts will have following code:

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { ReactiveFormsModule } from '@angular/forms';
import { HttpModule } from '@angular/http';
 
import { AppComponent } from './app.component';
import { ArticleComponent } from './article.component';
import { ArticleService } from './article.service';
 
@NgModule({
imports: [
BrowserModule,
HttpModule,
ReactiveFormsModule
],
declarations: [
AppComponent,
ArticleComponent
],
providers: [
ArticleService
],
bootstrap: [
AppComponent
]
})
export class AppModule { }

Now create a service file where we will make all the request to the server for CRUD operation. Command for creating service is ng g service artcle , for now I have just created a file named it article.service.ts. Let's have a look in the code inside this file.

import { Injectable } from '@angular/core';
import { Http, Response, Headers, URLSearchParams, RequestOptions } from '@angular/http';
import { Observable } from 'rxjs';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/catch';
 
import { Article } from './article';
 
@Injectable()
export class ArticleService {
//URL for CRUD operations
    articleUrl = "http://localhost:3000/article";
    //Create constructor to get Http instance
    constructor(private http:Http) {
    }
    
    //Fetch all articles
getAllArticles(): Observable<Article[]> {
return this.http.get(this.articleUrl+"/get-article")
              .map(this.extractData)
         .catch(this.handleError);
 
}
    //Create article
createArticle(article: Article):Observable<number> {
     let cpHeaders = new Headers({ 'Content-Type': 'application/json' });
let options = new RequestOptions({ headers: cpHeaders });
return this.http.post(this.articleUrl+"/create-article", article, options)
.map(success => success.status)
.catch(this.handleError);
}
    //Fetch article by id
getArticleById(articleId: string): Observable<Article> {
        let cpHeaders = new Headers({ 'Content-Type': 'application/json' });
        let options = new RequestOptions({ headers: cpHeaders });
        console.log(this.articleUrl +"/get-article-by-id?id="+ articleId);
        return this.http.get(this.articleUrl +"/get-article-by-id?id="+ articleId)
             .map(this.extractData)
             .catch(this.handleError);
}   
    //Update article
updateArticle(article: Article):Observable<number> {
     let cpHeaders = new Headers({ 'Content-Type': 'application/json' });
        let options = new RequestOptions({ headers: cpHeaders });
return this.http.put(this.articleUrl +"/update-article", article, options)
.map(success => success.status)
.catch(this.handleError);
}
//Delete article    
deleteArticleById(articleId: string): Observable<number> {
        let cpHeaders = new Headers({ 'Content-Type': 'application/json' });
        let options = new RequestOptions({ headers: cpHeaders });
        return this.http.delete(this.articleUrl +"/delete-article?id="+ articleId)
             .map(success => success.status)
             .catch(this.handleError);
}   
    private extractData(res: Response) {
        let body = res.json();
return body;
}
private handleError (error: Response | any) {
        console.error(error.message || error);
        return Observable.throw(error.status);
}
}

In the above file we have made all the http request for the CRUD operation. Observables of rxjs library has been used to handle the data fetching from http request.

Now let's move to the next file, article.component.ts. Here we have all the login part of the app. Let's have a look code inside this file:

import { Component, OnInit } from '@angular/core';
import { FormControl, FormGroup, Validators } from '@angular/forms';
 
import { ArticleService } from './article.service';
import { Article } from './article';
 
@Component({
selector: 'app-article',
templateUrl: './article.component.html',
styleUrls: ['./article.component.css']
})
export class ArticleComponent implements OnInit {
//Component properties
allArticles: Article[];
statusCode: number;
requestProcessing = false;
articleIdToUpdate = null;
processValidation = false;
//Create form
articleForm = new FormGroup({
title: new FormControl('', Validators.required),
category: new FormControl('', Validators.required)   
});
//Create constructor to get service instance
constructor(private articleService: ArticleService) {
}
//Create ngOnInit() and and load articles
ngOnInit(): void {
     this.getAllArticles();
}
//Fetch all articles
 
getAllArticles() {
        this.articleService.getAllArticles()
         .subscribe(
data => this.allArticles = data,
                errorCode => this.statusCode = errorCode);
                
}
//Handle create and update article
onArticleFormSubmit() {
     this.processValidation = true;
     if (this.articleForm.invalid) {
     return; //Validation failed, exit from method.
     }
     //Form is valid, now perform create or update
this.preProcessConfigurations();
     let article = this.articleForm.value;
     if (this.articleIdToUpdate === null) {
     //Generate article id then create article
this.articleService.getAllArticles()
     .subscribe(articles => {
            
         //Generate article id    
         let maxIndex = articles.length - 1;
         let articleWithMaxIndex = articles[maxIndex];
         let articleId = articleWithMaxIndex.id + 1;
         article.id = articleId;
         console.log(article,'this is form data---');
         //Create article
    this.articleService.createArticle(article)
             .subscribe(successCode => {
                    this.statusCode = successCode;
                    this.getAllArticles();  
                    this.backToCreateArticle();
                 },
                 errorCode => this.statusCode = errorCode
             );
         });        
     } else {
  //Handle update article
article.id = this.articleIdToUpdate;        
     this.articleService.updateArticle(article)
     .subscribe(successCode => {
         this.statusCode = successCode;
                 this.getAllArticles();  
                    this.backToCreateArticle();
             },
         errorCode => this.statusCode = errorCode);  
     }
}
//Load article by id to edit
loadArticleToEdit(articleId: string) {
this.preProcessConfigurations();
this.articleService.getArticleById(articleId)
     .subscribe(article => {
            console.log(article,'poiuytre');
         this.articleIdToUpdate = article.id;
                    this.articleForm.setValue({ title: article.title, category: article.category });
                    this.processValidation = true;
                    this.requestProcessing = false;
         },
         errorCode => this.statusCode = errorCode);
}
//Delete article
deleteArticle(articleId: string) {
this.preProcessConfigurations();
this.articleService.deleteArticleById(articleId)
     .subscribe(successCode => {
         //this.statusCode = successCode;
                    //Expecting success code 204 from server
                    this.statusCode = 204;
                 this.getAllArticles();  
                 this.backToCreateArticle();
             },
         errorCode => this.statusCode = errorCode);
}
//Perform preliminary processing configurations
preProcessConfigurations() {
this.statusCode = null;
     this.requestProcessing = true;
}
//Go back from update to create
backToCreateArticle() {
this.articleIdToUpdate = null;
this.articleForm.reset(); 
     this.processValidation = false;
}
}

Now we have to show the task over browser, So lets have a look inside article.component.html file.

<h1 class="text-center">Angular 7 CRUD Demo App</h1>
<h3 class="text-center" *ngIf="articleIdToUpdate; else create">
Update Article for Id: {{articleIdToUpdate}}
</h3>
<ng-template #create>
<h3 class="text-center"> Create New Article </h3>
</ng-template>
<div>
<form [formGroup]="articleForm" (ngSubmit)="onArticleFormSubmit()">
<table class="table-striped" style="margin:0 auto;">
<tr><td>Enter Title</td><td><input formControlName="title">
   <label *ngIf="articleForm.get('title').invalid && processValidation" [ngClass] = "'error'"> Title is required. </label>
 </td></tr>
<tr><td>Enter Category</td><td><input formControlName="category">
   <label *ngIf="articleForm.get('category').invalid && processValidation" [ngClass] = "'error'"> Category is required. </label>
  </td></tr>  
<tr><td colspan="2">
   <button class="btn btn-default" *ngIf="!articleIdToUpdate">CREATE</button>
    <button class="btn btn-default" *ngIf="articleIdToUpdate">UPDATE</button>
   <button (click)="backToCreateArticle()" *ngIf="articleIdToUpdate">Go Back</button>
  </td></tr>
</table>
</form>
<br/>
<div class="text-center" *ngIf="statusCode; else processing">
<div *ngIf="statusCode === 201" [ngClass] = "'success'">
   Article added successfully.
</div>
<div *ngIf="statusCode === 409" [ngClass] = "'success'">
Article already exists.
</div>   
<div *ngIf="statusCode === 200" [ngClass] = "'success'">
Article updated successfully.
</div>   
<div *ngIf="statusCode === 204" [ngClass] = "'success'">
Article deleted successfully.
</div>   
<div *ngIf="statusCode === 500" [ngClass] = "'error'">
Internal Server Error.
</div> 
</div>
<ng-template #processing>
  <img *ngIf="requestProcessing" src="assets/images/loading.gif">
</ng-template>
</div>
<h3 class="text-center">Article List</h3>
<table class="table-striped" style="margin:0 auto;" *ngIf="allArticles">
<tr><th> Id</th> <th>Title</th><th>Category</th><th></th><th></th></tr>
<tr *ngFor="let article of allArticles" >
<td>{{article.id}}</td> <td>{{article.title}}</td> <td>{{article.category}}</td>
  <td><button class="btn btn-default" type="button" (click)="loadArticleToEdit(article.id)">Edit</button> </td>
  <td><button class="btn btn-default" type="button" (click)="deleteArticle(article.id)">Delete</button></td>
</tr>
</table>

Now since I have created server and client two separate folder for nodejs and angular task. So will run both the apps with npm start over two tabs of terminal.

On the browser, over link http://localhost:4200. App will look like below

Angular CRUD with Nodejs and MySQL Example

That’s all for now. Thank you for reading and I hope this post will be very helpful for creating CRUD operations with angular7,node.js & mysql.

================================================

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Angular 8 Forms Tutorial - Reactive Forms Validation Example

Angular 8 Forms Tutorial - Reactive Forms Validation Example

In this article, you''ll see a quick example of how to setup form validation in Angular 8 using Reactive Forms.

In this article, you''ll see a quick example of how to setup form validation in Angular 8 using Reactive Forms.

The example is a simple registration form with pretty standard fields for title, first name, last name, email, password, confirm password and an accept Ts & Cs checkbox. All fields are required including the checkbox, the email field must be a valid email address and the password field must have a min length of 6. There's also a custom validator called MustMatch which is used to validate that the confirm password and password fields match.

I've setup the form to validate on submit rather than as soon as each field is changed, this is implemented with a submitted property in the app component that is set to true when the form is submitted for the first time, and reset to false if the cancel button is clicked.

Styling of the example is all done with Bootstrap 4.3 CSS.

See on StackBlitz at https://stackblitz.com/edit/angular-8-reactive-form-validation

Reactive Forms Validation App Component

The app component defines the form fields and validators for our registration form using an Angular FormBuilder to create an instance of a FormGroup that is stored in the registerForm property. The registerForm is then bound to the form in the app template below using the [formGroup] directive.

I also added a getter f as a convenience property to make it easier to access form controls from the template. So for example you can access the confirmPassword field in the template using f.confirmPassword instead of registerForm.controls.confirmPassword.

import { Component, OnInit } from '@angular/core';
import { FormBuilder, FormGroup, Validators } from '@angular/forms';

// import custom validator to validate that password and confirm password fields match
import { MustMatch } from './_helpers/must-match.validator';

@Component({ selector: 'app', templateUrl: 'app.component.html' })
export class AppComponent implements OnInit {
    registerForm: FormGroup;
    submitted = false;

    constructor(private formBuilder: FormBuilder) { }

    ngOnInit() {
        this.registerForm = this.formBuilder.group({
            title: ['', Validators.required],
            firstName: ['', Validators.required],
            lastName: ['', Validators.required],
            email: ['', [Validators.required, Validators.email]],
            password: ['', [Validators.required, Validators.minLength(6)]],
            confirmPassword: ['', Validators.required],
            acceptTerms: [false, Validators.requiredTrue]
        }, {
            validator: MustMatch('password', 'confirmPassword')
        });
    }

    // convenience getter for easy access to form fields
    get f() { return this.registerForm.controls; }

    onSubmit() {
        this.submitted = true;

        // stop here if form is invalid
        if (this.registerForm.invalid) {
            return;
        }

        // display form values on success
        alert('SUCCESS!! :-)\n\n' + JSON.stringify(this.registerForm.value, null, 4));
    }

    onReset() {
        this.submitted = false;
        this.registerForm.reset();
    }
}
Reactive Forms Validation App Template

The app component template contains all the html markup for displaying the example registration form in your browser. The form element uses the [formGroup] directive to bind to the registerForm FormGroup in the app component above.

The form binds the form submit event to the onSubmit() handler in the app component using the Angular event binding (ngSubmit)="onSubmit()". Validation messages are displayed only after the user attempts to submit the form for the first time, this is controlled with the submitted property of the app component.

The cancel button click event is bound to the onReset() handler in the app component using the Angular event binding (click)="onReset()".



    ##### Angular 8 Reactive Form Validation

    
        
            
                
                    Title
                    
                        
                        Mr
                        Mrs
                        Miss
                        Ms
                    
                    
                        Title is required

                    
                
                
                    First Name
                    
                    
                        First Name is required

                    
                
                
                    Last Name
                    
                    
                        Last Name is required

                    
                
            
            
                Email
                
                
                    Email is required

                    Email must be a valid email address

                
            
            
                
                    Password
                    
                    
                        Password is required

                        Password must be at least 6 characters

                    
                
                
                    Confirm Password
                    
                    
                        Confirm Password is required

                        Passwords must match

                    
                
            
            
                
                Accept Terms & Conditions
                Accept Ts & Cs is required

            
            
                Register
                Cancel
            
        
    

Reactive Forms Custom "Must Match" Validator

The custom MustMatch validator is used in this example to validate that both of the password fields - password and confirmPassword - are matching. However it can be used to validate that any pair of fields is matching (e.g. email and confirm email fields).

It works slightly differently than a typical custom validator because I'm setting the error on the second field instead of returning it to be set on the formGroup. I did it this way because I think it makes the template a bit cleaner and more intuitive, the mustMatch validation error is displayed below the confirmPassword field so I think it makes sense that the error is attached the the confirmPassword form control.

import { FormGroup } from '@angular/forms';

// custom validator to check that two fields match
export function MustMatch(controlName: string, matchingControlName: string) {
    return (formGroup: FormGroup) => {
        const control = formGroup.controls[controlName];
        const matchingControl = formGroup.controls[matchingControlName];

        if (matchingControl.errors && !matchingControl.errors.mustMatch) {
            // return if another validator has already found an error on the matchingControl
            return;
        }

        // set error on matchingControl if validation fails
        if (control.value !== matchingControl.value) {
            matchingControl.setErrors({ mustMatch: true });
        } else {
            matchingControl.setErrors(null);
        }
    }
}
Reactive Forms Validation App Module

There isn't much going on in the app module other than the standard stuff, the main thing you need to remember for using reactive forms in Angular is to import the ReactiveFormsModule from '@angular/forms' and include it in the imports array of the @NgModule decorator.

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { ReactiveFormsModule } from '@angular/forms';

import { AppComponent } from './app.component';

@NgModule({
    imports: [
        BrowserModule,
        ReactiveFormsModule
    ],
    declarations: [
        AppComponent
    ],
    bootstrap: [AppComponent]
})
export class AppModule { }

Angular 8 Pagination Example and Tutorial

Angular 8 Pagination Example and Tutorial

Pagination is the best way to show huge number of records in series for any application. Also showing/fetching thousands of record at one go will affect the performance of the application.

Pagination is the best way to show huge number of records in series for any application. Also showing/fetching thousands of record at one go will affect the performance of the application.

For example, when you search something that returns a large number of records which cannot be shown on a single web page therefore, those records are part into number of pages that can be accessed through links via pagination structure.

So today in this demo we will discuss the simple pagination in Angular 8.

Step 1: Create a basic app with angular cli
ng new angular8-simple-pagination-example

By typing the above command we will see a basic angular app created on the current folder. So move to the created folder by typing **cd angular8-simple-pagination-example/. **You can check the newly created app by typing http://localhost:4200 on the browser.

Step 2: install ngx-pagination pagination dependency from terminal

So run the below command over terminal

npm install ngx-pagination --save

Step 3: Create dummy records for pagination

Now we will create static data to show the pagination. So lets have a look on the code under file **app.component.ts **

import { Component } from '@angular/core';
import {NgxPaginationModule} from 'ngx-pagination';
@Component({
   selector: 'app-root',
   templateUrl: './app.component.html',
   styleUrls: ['./app.component.css']
})
export class AppComponent {
   title = 'simple pagination demo';
   collection = [];
   constructor(){
     for(let i=1;i<=100;i++){
       let Obj = {'name': `Employee Name ${i}`,'code': `EMP00 ${i}`}
       this.collection.push(Obj);
     }
   }
}

In the above file, we can see that inside constructor we have created a loop for created dummy record for 100 employees having employee name & code for showing pagination.

Step 4: Import dependency in app.module.ts

Now let's have a look on the code inside **app.module.ts **where the ngx-pagination module has been imported

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';
 
import { NgxPaginationModule } from 'ngx-pagination';
import { AppComponent } from './app.component';
 
@NgModule({
declarations: [
AppComponent
],
imports: [
BrowserModule,
NgxPaginationModule
],
providers: [],
bootstrap: [AppComponent]
})
export class AppModule { }

Step 5: Update view from app.component.html

Now one last step needed to do is, add the below code anywhere inside app.component.html

*  Emp Name | Emp code
 {{item.name}} | {{item.code}} 


Now, we are done with all the needed steps for the pagination in our angular application.

Step 6: Run the app

Run the app over the terminal with npm start and check the app after typing the url http://localhost:4200/.** **A page will open like below:

Conclusion

By following these easy steps we can easily achieve the client side pagination in Angular 8 application. If you want to impliment server side pagination in angular8 Server Side Pagination in Angular Example and Tutorial . You can also find other demos of Angular Sample Application here to start working on enterprise level application. Click here to view more about the pagination package over npm.

Introduction New Features in TypeScript 3.7 and How to Use Them

Introduction New Features in TypeScript 3.7 and How to Use Them

The TypeScript 3.7 release is coming soon, and it's going to be a big one.

The target release date is November 5th, and there are some seriously exciting headline features included:

  • Assert signatures.
  • Recursive type aliases.
  • Top-level await.
  • Null coalescing.
  • Optional chaining.

Personally, I'm super excited about this, they're going to whisk away all sorts of annoyances that I've been fighting in TypeScript while building HTTP Toolkit.

If you haven't been paying close attention to the TypeScript development process though, it's probably not clear what half of these mean, or why you should care. Let's talk through all of them.

Assert Signatures

This is a brand-new and little-known TypeScript feature, which allows you to write functions that act like type guards as a side-effect, rather than explicitly returning their boolean result.

It's easiest to demonstrate this with a JavaScript example:

function assertString(input) { 
  if (typeof input === 'string') 
    return; 
  else 
    throw new Error('Input must be a string!'); 
} 
function doSomething(input) { 
  assertString(input); 
  // ... Use input, confident that it's a string 
} 
doSomething('abc'); 
// All good doSomething(123); // Throws an error

This pattern is neat and useful, and you can't use it in TypeScript today.

TypeScript can't know that you've guaranteed the type of input after it's run assertString. Typically, people just make the argument input: string to avoid this, and that's good. But, it also just pushes the type checking problem somewhere else, and in cases where you just want to fail hard, it's useful to have this option available.

Fortunately, soon we will:

// With TS 3.7 
function assertString(input: any): 
	asserts input is string { 
      // <-- the magic 
      if (typeof input === 'string') 
        return; 
      else 
        throw new Error('Input must be a string!'); 
    } 
function doSomething(input: string | number) { 
  assertString(input); 
  // input's type is just 'string' here }

Here assert input is string means that if this function ever returns, TypeScript can narrow the type of input to string, just as if it was inside an if block with a type guard.

To make this safe, that means if the assert statement isn't true then your assert function must either throw an error or not return at all (kill the process, infinite loop, you name it).

That's the basics, but this actually lets you pull some really neat tricks:

// With TS 3.7 
// Asserts that input is truthy, throwing immediately if not: 
function assert(input: any): 
	asserts input { // <-- not a typo 
      if (!input) 
        throw new Error('Not a truthy value'); 
    } 
declare const x: number | string | undefined; 
assert(x); // Narrows x to number | string 
// Also usable with type guarding expressions! 
assert(typeof x === 'string'); 
// Narrows x to string // -- Or use assert in your tests: -- 
const a: Result | Error = doSomethingTestable(); 
expect(a).is.instanceOf(result); 
// 'instanceOf' could 'asserts a is Result' 
expect(a.resultValue).to.equal(123); 
// a.resultValue is now legal // -- Use as a safer ! that throws immediately if 
// you're wrong -- 
function assertDefined<T>(obj: T): 
	asserts obj is NonNullable<T> { 
      if (obj === undefined || obj === null) { 
        throw new Error('Must not be a nullable value'); 
      } 
    } 
declare const x: string | undefined; 
// Gives y just 'string' as a type, could throw elsewhere later: 
const y = x!; 
// Gives y 'string' as a type, or throws immediately if you're wrong: 
assertDefined(x); const z = x; 
// -- Or even update types to track a function's side-effects -- 
type X<T extends string | {}> = { value: T }; 
// Use asserts to narrow types according to side effects: 
function setX<T extends string | {}>(x: X<any>, v: T): 
	asserts x is X<T> { 
      x.value = v; 
    } 
	declare let x: X<any>; 
// x is now { value: any }; 
setX(x, 123); 
// x is now { value: number };

This is still in flux, so don't take it as the definite result, and keep an eye on the pull request if you want the final details.

There's even a discussion there about allowing functions to assert something and return a type, which would let you extend the final example above to track a much wider variety of side effects, but we'll have to wait and see how that plays out.

Top-Level Await

Async/await is amazing and makes promises dramatically cleaner to use.

Unfortunately, though, you can't use them at the top level. This might not be something you care about much in a TS library or application, but if you're writing a runnable script or using TypeScript in a REPL, then this gets super annoying.

It's even worse if you're used to frontend development, since top-level await has been working nicely in the Chrome and Firefox console for a couple of years now.

Fortunately though, a fix is coming. This is actually a general stage-3 JS proposal, so it'll be everywhere else eventually too, but for TS devs 3.7 is where the magic happens.

This one's simple, but let's have another quick demo anyway:


// Your only solution right now for a script that does something async: 
async function doEverything() { 
  ... 
  const response = await fetch('http://example.com'); 
  ... 
} 
  
doEverything(); // <- eugh (could use an IIFE instead, but even more eugh)

With top-level await:

// With TS 3.7: 
// Your script: ... 
const response = await fetch('http://example.com'); 
// ...

There's a notable gotcha here: if you're not writing a script, or using a REPL, don't write this at the top level, unless you really know what you're doing!

It's totally possible to use this to write modules that do blocking async steps when imported. That can be useful for some niche cases, but people tend to assume that their import statement is a synchronous, reliable, and fairly quick operation, and you could easily hose your codebase's startup time if you start blocking imports for complex async processes (even worse, processes that can fail).

This is somewhat mitigated by the semantics of imports of async modules: they're imported and run in parallel, so the importing module effectively waits for Promise.all(importedModules) before being executed.

Rich Harris wrote an excellent piece on a previous version of this spec before that change when imports ran sequentially and this problem was much worse), which makes for good background reading on the risks here if you're interested.

It's also worth noting that this is only useful for module systems that support asynchronous imports. There isn't yet a formal spec for how TS will handle this, but that likely means that a very recent target configuration, and, either ES Modules or Webpack v5 (whose alphas have experimental support), will be used at runtime.

Recursive Type Aliases

If you're ever tried to define a recursive type in TypeScript, you may have run into StackOverflow questions like this: https://stackoverflow.com/questions/47842266/recursive-types-in-typescript.

Right now, you can't. Interfaces can be recursive, but there are limitations to their expressiveness, and type aliases can't. That means right now, you need to combine the two: define a type alias and extract the recursive parts of the type into interfaces. It works, but it's messy, and we can do better.

As a concrete example, this is the suggested type definition for JSON data:

type JSONValue = | string | number | boolean | JSONObject | JSONArray; 
interface JSONObject { [x: string]: JSONValue; } 
interface JSONArray extends Array<JSONValue> { }

That works, but the extra interfaces are only there because they're required to get around the recursion limitation.

Fixing this requires no new syntax; it just removes that restriction, so the below compiles:

// With TS 3.7: 
type JSONValue = | string | number | boolean | { [x: string]: JSONValue } | Array<JSONValue>;

Right now, that fails to compile with Type alias 'JSONValue' circularly references itself. Soon though, soon...

Null Coalescing

Aside from being difficult to spell, this one is quite simple and easy. It's based on a JavaScript stage-3 proposal, which means it'll also be coming to your favorite vanilla JavaScript environment soon (if it hasn't already).

In JavaScript, there's a common pattern for handling default values, and falling back to the first valid result of a defined group. It looks something like this:

// Use the first of firstResult/secondResult which is truthy: 
const result = firstResult || secondResult; 
// Use configValue from provided options if truthy, or 'default' if not: 
this.configValue = options.configValue || 'default';

This is useful in a host of cases, but due to some interesting quirks in JavaScript, it can catch you out. If firstResult or options.configValue can meaningfully be set to false, an empty string or 0, then this code has a bug. If those values are set, then when considered as booleans they're falsy, so the fallback value (secondResult / 'default') is used anyway.

Null coalescing fixes this. Instead of the above, you'll be able to write:

// With TS 3.7: 
// Use the first of firstResult/secondResult which is *defined*: 
const result = firstResult ?? secondResult; 
// Use configSetting from provided options if *defined*, or 'default' if not: 
this.configValue = options.configValue ?? 'default';

?? differs from || in that it falls through to the next value only if the first argument is null or undefined, not falsy. That fixes our bug. If you pass false as firstResult, that will be used instead of secondResult because, while it's falsy, it is still defined, and that's all that's required.

It's simple but super-useful, as it takes away a whole class of bugs.

Optional Chaining

Last but not least, optional chaining is another stage-3 proposal that is making its way into TypeScript.

This is designed to solve an issue faced by developers in every language: how do you get data out of a data structure when some or all of it might not be present?

Right now, you might do something like this:

// To get data.key1.key2, if any level could be null/undefined: 
let result = data ? (data.key1 ? data.key1.key2 : undefined) : undefined; 
// Another equivalent alternative: 
let result = ((data || {}).key1 || {}).key2;

Nasty! This gets much much worse if you need to go deeper, and although the second example works at runtime, it won't even compile in TypeScript, since the first step could be {}, in which case key1 isn't a valid key at all.

This gets still more complicated if you're trying to get into an array, or there's a function call somewhere in this process.

There's a host of other approaches to this, but they're all noisy, messy & error-prone. With optional chaining, you can do this:

// With TS 3.7: 
// Returns the value is it's all defined & non-null, or undefined if not. 
let result = data?.key1?.key2; 
// The same, through an array index or property, if possible: 
array?.[0]?.['key']; 
// Call a method, but only if it's defined: 
obj.method?.(); 
// Get a property, or return 'default' if any step is not defined: 
let result = data?.key1?.key2 ?? 'default';

The last case shows how neatly some of these dovetails together: null coalescing + optional chaining is a match made in heaven.

One gotcha: this will return undefined for missing values, even if they were null, e.g. in cases like (null)?.key (returns undefined). A small point, but one to watch out for if you have a lot of null in your data structures.

That's the lot! That should outline all the essentials for these features, but there are lots of smaller improvements, fixes, and editor support improvements coming too, so take a look at the official roadmap if you want to get into the nitty-gritty.