Jenkins Cheat Sheet – A Beginner’s Guide to Jenkins

A handy Jenkins cheat sheet which covers the basics of Jenkins along with the best practices that are needed for software development.

Are you a DevOps Enthusiast looking to explore different tools? If yes, then you have landed at the right place. DevOps Engineers are the most demanded and payed professionals all around the world. With this in mind let me introduce you to the most popular DevOps Tool, Jenkins. This Jenkins cheat sheet is for beginners who have prior knowledge about how a software development process occurs.

Jenkins Cheat Sheet

Continuous Integration is a software development practice in which developers are required to frequently commit changes to the source code in a shared repository. Each commit is then continuously pulled & built. Jenkins is an open source, Continuous Integration (CI) tool, written in Java. It continuously pulls, builds and tests any code commits made by a developer with the help of plugins.

Installation

Let’s start by installing Jenkins. This installation is specific to systems operating on Ubuntu. Follow the below steps:

Step 1: Install Java
$ sudo apt update
$ sudo apt install openjdk-8-jdk

Step 2: Add Jenkins Repository
$ wget -q -O - https://pkg.jenkins.io/debian/jenkins.io.key | sudo apt-key add –

Step 3: Add Jenkins repo to the system
$ sudo sh -c 'echo deb http://pkg.jenkins.io/debian-stable binary/ > /etc/apt/sources.list.d/jenkins.list'

Step 4: Install Jenkins
$ sudo apt update
$ sudo apt install Jenkins

Step 5: Verify installation
$ systemctl status Jenkins

Step 6: Once Jenkins is up and running, access it from the link:
http://localhost:8080

Most commonly used Jenkins Plugins

Jenkins comes with over 2000 plugins and each plugin has a unique functionality. But when it comes to software development most developers use a set of plugins, such as

• Maven
• Git
• Ant
• Docker
• Amazon EC2
• HTML publisher
• Copy artifact

Follow the below step to install the above plugins or any other Jenkins plugin.

Jenkins Dashboard -> Manage Jenkins -> Manage Plugins -> Available  

In the filter text field enter the name of the plugin you want to install.

Different Types of Jenkins Jobs

Jenkins provides the option of choosing from different types of jobs to build your project.

Below are the types of jobs you can choose from:

• Freestyle

Freestyle build jobs are general-purpose build jobs, which provides maximum flexibility. It can be used for any type of project.

• Pipeline

This project runs the entire software development workflow as code. Instead of creating several jobs for each stage of software development, you can now run the entire workflow as one code.

• Multiconfiguration

The multiconfiguration project allows you to run the same build job on different environments. It is used for testing an application in different environments.

• Folder

This project allows users to create folders to organize and categorize similar jobs in one folder or sub folder.

• GitHub Organization

This project scans your entire GitHub organization and creates Pipeline jobs for each repository containing a Jenkinsfile

• Multibranch pipeline

This project type lets you implement different Jenkinsfiles for different branches of the same project.

Build Pipeline

Build pipeline can be used to chain several jobs together and run them in a sequence. Let’s see how to install Build Pipeline:

Jenkins Dashboard -> Manage Jenkins -> Manage Plugins -> Available  

In the filter text field enter the name of the plugin you want to install.

Build Pipeline Example

Step 1: Create 3 freestyle Jobs (Job1, Job2, Job3)

Step 2: Chain the 3 Jobs together
Job1 -> configure -> Post Build -> Build other projects -> Job2
Job2 -> configure -> Post Build -> Build other projects -> Job3

Step 3: Create a build pipeline view
Jenkins Dashboard -> Add view -> Enter a name -> Build pipeline view -> ok ->
configure -> Pipeline flow -> Select Initial job -> Job1 -> ok

Step 4: Run the Build Pipeline

Jenkins Pipeline

Jenkins pipeline is a single platform that runs the entire _pipeline as code. _Instead of building several jobs for each phase, you can now code the entire workflow and put it in a Jenkinsfile.

Jenkinsfile is a text file that stores the pipeline as code. It is written using the Groovy DSL_. _It can be written based on two syntaxes:

• Scripted pipeline

Code is written on the Jenkins UI instance and is enclosed within the node block

node {
      scripted pipeline code
}

• Declarative pipeline

Code is written locally in a file and is checked into a SCM and is enclosed within the pipeline block

pipeline {
      declarative pipeline code
}

Pipeline Concepts

The below fundamentals are common to both, scripted and declarative pipeline:

1. Pipeline: A user defined block which contains all the stages. It is a key part of declarative pipeline syntax.

2. Node: A node is a machine that executes an entire workflow. It is a key part of the scripted pipeline syntax.

3. Agent: instructs Jenkins to allocate an executor for the builds. It is defined for an entire pipeline or a specific stage.

   It has the following parameters:

• Any: Runs pipeline/ stage on any available agent
• None: applied at the root of the pipeline, it indicates that there is no global agent for the entire pipeline & each stage must specify its own agent
• Label: Executes the pipeline/stage on the labelled agent.
• Docker: Uses docker container as an execution environment for the pipeline or a specific stage.

1. Stages: It contains all the work; each stage performs a specific task.
2. Steps: steps are carried out in sequence to execute a stage

Create your first Jenkins Pipeline

After installing Jenkins, building jobs using the Build pipeline and briefly discussing about pipeline concepts, let’s see how to create a Jenkins pipeline.

Follow the below steps to create both, a scripted pipeline and a declarative pipeline:

Jenkins Pipeline syntax example

Step 1: Log into Jenkins and select ‘New Item from the Dashboard'

Step 2: Next, enter a name for your pipeline and select ‘Pipeline project’. Click ‘ok’ to proceed

Step 3: Scroll down to the pipeline and choose if you want a Declarative or Scripted pipeline

Step 4a: If you want a Scripted pipeline, then choose ‘pipeline script’ and start typing your code

Step 4b: If you want a Declarative Pipeline, select ‘Pipeline script from SCM’ and choose your SCM and enter your repository URL

Step 5: Within the Script path is the name of the Jenkinsfile that is going to be accessed from your SCM to run. Finally click on ‘apply’ and ‘save’
node {
     stage(‘SCM checkout’) {
          //Checkout from your SCM(Source Control Management)
          //For eg: Git Checkout
     }
     stage(‘Build’) {
          //Compile code
          //Install dependencies
          //Perform Unit Test, Integration Test
     }
     stage(‘Test’) {
          //Resolve test server dependencies
          //Perform UAT
     }
     stage(‘Deploy’) {
          //Deploy code to prod server
          //Solve dependency issues
     }
}

Jenkins Tips and Tricks

Start, stop and restart Jenkins

Follow the below command to start, stop and restart Jenkins through the CLI.

$ sudo service jenkins restart
$ sudo service jenkins stop
$ sudo service jenkins start

Deploy a custom build of a core plugin

Step 1: Stop Jenkins.

Step 2: Copy the custom HPI to $Jenkins_Home/plugins.

Step 3: Delete the previously expanded plugin directory.

Step 4: Make an empty file called <plugin>.hpi.pinned.

Step 5: Start Jenkins.

Schedule a build periodically

Jenkins uses a cron expressions to schedule a job. Each line consists of 5 fields separated by TAB or whitespace:

Syntax: (Minute Hour DOM Month DOW)

MINUTE: Minutes in one hour (0-59)

HOURS: Hours in one day (0-23)

DAYMONTH: Day in a month (1-31)

MONTH: Month in a year (1-12)

DAYWEEK: Day of the week (0-7) where 0 and 7 are sunday

Example: H/2 * * * * (schedule your build for every 2 minutes)

Try this example:

H/2 * * * * (schedules your build for every 2 minutes)

Snippet Generator

A tool that lets users generate code for individual steps in a scripted pipeline. Let’s look at an example:

Step 1: Create a pipeline job > configure

Step 2: Select pipeline script from pipeline definition

Step 3: Click on Pipeline syntax > snippet generator

Step 4: Step > select Git > enter repo URL

Step 5: Scroll down > Generate pipeline script

Step 6: Copy the script into your pipeline script UI

Below is an image of the Snippet Generator. You can select from a variety of steps and generate a code for each step.

Below is an image of the Scripted pipeline UI with the code generated from snippet generator

Download Jenkins Cheat Sheet Edureka

#jenkins #devops

What is GEEK

Buddha Community

Test_cov_console: Flutter Console Coverage Test

Flutter Console Coverage Test

This small dart tools is used to generate Flutter Coverage Test report to console

How to install

Add a line like this to your package's pubspec.yaml (and run an implicit flutter pub get):

dev_dependencies:
  test_cov_console: ^0.2.2

How to run

run the following command to make sure all flutter library is up-to-date

flutter pub get
Running "flutter pub get" in coverage...                            0.5s

run the following command to generate lcov.info on coverage directory

flutter test --coverage
00:02 +1: All tests passed!

run the tool to generate report from lcov.info

flutter pub run test_cov_console
---------------------------------------------|---------|---------|---------|-------------------|
File                                         |% Branch | % Funcs | % Lines | Uncovered Line #s |
---------------------------------------------|---------|---------|---------|-------------------|
lib/src/                                     |         |         |         |                   |
 print_cov.dart                              |  100.00 |  100.00 |   88.37 |...,149,205,206,207|
 print_cov_constants.dart                    |    0.00 |    0.00 |    0.00 |    no unit testing|
lib/                                         |         |         |         |                   |
 test_cov_console.dart                       |    0.00 |    0.00 |    0.00 |    no unit testing|
---------------------------------------------|---------|---------|---------|-------------------|
 All files with unit testing                 |  100.00 |  100.00 |   88.37 |                   |
---------------------------------------------|---------|---------|---------|-------------------|

Optional parameter

If not given a FILE, "coverage/lcov.info" will be used.
-f, --file=<FILE>                      The target lcov.info file to be reported
-e, --exclude=<STRING1,STRING2,...>    A list of contains string for files without unit testing
                                       to be excluded from report
-l, --line                             It will print Lines & Uncovered Lines only
                                       Branch & Functions coverage percentage will not be printed
-i, --ignore                           It will not print any file without unit testing
-m, --multi                            Report from multiple lcov.info files
-c, --csv                              Output to CSV file
-o, --output=<CSV-FILE>                Full path of output CSV file
                                       If not given, "coverage/test_cov_console.csv" will be used
-t, --total                            Print only the total coverage
                                       Note: it will ignore all other option (if any), except -m
-p, --pass=<MINIMUM>                   Print only the whether total coverage is passed MINIMUM value or not
                                       If the value >= MINIMUM, it will print PASSED, otherwise FAILED
                                       Note: it will ignore all other option (if any), except -m
-h, --help                             Show this help

example run the tool with parameters

flutter pub run test_cov_console --file=coverage/lcov.info --exclude=_constants,_mock
---------------------------------------------|---------|---------|---------|-------------------|
File                                         |% Branch | % Funcs | % Lines | Uncovered Line #s |
---------------------------------------------|---------|---------|---------|-------------------|
lib/src/                                     |         |         |         |                   |
 print_cov.dart                              |  100.00 |  100.00 |   88.37 |...,149,205,206,207|
lib/                                         |         |         |         |                   |
 test_cov_console.dart                       |    0.00 |    0.00 |    0.00 |    no unit testing|
---------------------------------------------|---------|---------|---------|-------------------|
 All files with unit testing                 |  100.00 |  100.00 |   88.37 |                   |
---------------------------------------------|---------|---------|---------|-------------------|

report for multiple lcov.info files (-m, --multi)

It support to run for multiple lcov.info files with the followings directory structures:
1. No root module
<root>/<module_a>
<root>/<module_a>/coverage/lcov.info
<root>/<module_a>/lib/src
<root>/<module_b>
<root>/<module_b>/coverage/lcov.info
<root>/<module_b>/lib/src
...
2. With root module
<root>/coverage/lcov.info
<root>/lib/src
<root>/<module_a>
<root>/<module_a>/coverage/lcov.info
<root>/<module_a>/lib/src
<root>/<module_b>
<root>/<module_b>/coverage/lcov.info
<root>/<module_b>/lib/src
...
You must run test_cov_console on <root> dir, and the report would be grouped by module, here is
the sample output for directory structure 'with root module':
flutter pub run test_cov_console --file=coverage/lcov.info --exclude=_constants,_mock --multi
---------------------------------------------|---------|---------|---------|-------------------|
File                                         |% Branch | % Funcs | % Lines | Uncovered Line #s |
---------------------------------------------|---------|---------|---------|-------------------|
lib/src/                                     |         |         |         |                   |
 print_cov.dart                              |  100.00 |  100.00 |   88.37 |...,149,205,206,207|
lib/                                         |         |         |         |                   |
 test_cov_console.dart                       |    0.00 |    0.00 |    0.00 |    no unit testing|
---------------------------------------------|---------|---------|---------|-------------------|
 All files with unit testing                 |  100.00 |  100.00 |   88.37 |                   |
---------------------------------------------|---------|---------|---------|-------------------|
---------------------------------------------|---------|---------|---------|-------------------|
File - module_a -                            |% Branch | % Funcs | % Lines | Uncovered Line #s |
---------------------------------------------|---------|---------|---------|-------------------|
lib/src/                                     |         |         |         |                   |
 print_cov.dart                              |  100.00 |  100.00 |   88.37 |...,149,205,206,207|
lib/                                         |         |         |         |                   |
 test_cov_console.dart                       |    0.00 |    0.00 |    0.00 |    no unit testing|
---------------------------------------------|---------|---------|---------|-------------------|
 All files with unit testing                 |  100.00 |  100.00 |   88.37 |                   |
---------------------------------------------|---------|---------|---------|-------------------|
---------------------------------------------|---------|---------|---------|-------------------|
File - module_b -                            |% Branch | % Funcs | % Lines | Uncovered Line #s |
---------------------------------------------|---------|---------|---------|-------------------|
lib/src/                                     |         |         |         |                   |
 print_cov.dart                              |  100.00 |  100.00 |   88.37 |...,149,205,206,207|
lib/                                         |         |         |         |                   |
 test_cov_console.dart                       |    0.00 |    0.00 |    0.00 |    no unit testing|
---------------------------------------------|---------|---------|---------|-------------------|
 All files with unit testing                 |  100.00 |  100.00 |   88.37 |                   |
---------------------------------------------|---------|---------|---------|-------------------|

Output to CSV file (-c, --csv, -o, --output)

flutter pub run test_cov_console -c --output=coverage/test_coverage.csv

#### sample CSV output file:
File,% Branch,% Funcs,% Lines,Uncovered Line #s
lib/,,,,
test_cov_console.dart,0.00,0.00,0.00,no unit testing
lib/src/,,,,
parser.dart,100.00,100.00,97.22,"97"
parser_constants.dart,100.00,100.00,100.00,""
print_cov.dart,100.00,100.00,82.91,"29,49,51,52,171,174,177,180,183,184,185,186,187,188,279,324,325,387,388,389,390,391,392,393,394,395,398"
print_cov_constants.dart,0.00,0.00,0.00,no unit testing
All files with unit testing,100.00,100.00,86.07,""

Installing

Use this package as an executable

Install it

You can install the package from the command line:

dart pub global activate test_cov_console

Use it

The package has the following executables:

$ test_cov_console

Use this package as a library

Depend on it

Run this command:

With Dart:

 $ dart pub add test_cov_console

With Flutter:

 $ flutter pub add test_cov_console

This will add a line like this to your package's pubspec.yaml (and run an implicit dart pub get):

dependencies:
  test_cov_console: ^0.2.2

Alternatively, your editor might support dart pub get or flutter pub get. Check the docs for your editor to learn more.

Import it

Now in your Dart code, you can use:

import 'package:test_cov_console/test_cov_console.dart';

example/lib/main.dart

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
        // This makes the visual density adapt to the platform that you run
        // the app on. For desktop platforms, the controls will be smaller and
        // closer together (more dense) than on mobile platforms.
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key? key, required this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also a layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Invoke "debug painting" (press "p" in the console, choose the
          // "Toggle Debug Paint" action from the Flutter Inspector in Android
          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
          // to see the wireframe for each widget.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

Author: DigitalKatalis
Source Code: https://github.com/DigitalKatalis/test_cov_console 
License: BSD-3-Clause license

#flutter #dart #test 

What is Bitcoin Cash? - A Beginner’s Guide

Bitcoin Cash was created as a result of a hard fork in the Bitcoin network. The Bitcoin Cash network supports a larger block size than Bitcoin (currently 32mb as opposed to Bitcoin’s 1mb).

Later on, Bitcoin Cash forked into Bitcoin SV due to differences in how to carry on its developments.

That’s Bitcoin Cash in a nutshell. If you want a more detailed review watch the complete video. Here’s what I’ll cover:

0:50 - Bitcoin forks
2:06 - Bitcoin’s block size debate
3:35 - Big blocks camp
4:26 - Small blocks camp
5:16 - Small blocks vs. big blocks arguments
7:05 - How decisions are made in the Bitcoin network
10:14 - Block size debate resolution
11:06 - Bitcoin cash intro
11:28 - BTC vs. BCH
12:13 - Bitcoin Cash (ABC) vs. Bitcoin SV
13:09 - Conclusion
📺 The video in this post was made by 99Bitcoins
The origin of the article: https://www.youtube.com/watch?v=ONhbb4YVRLM
🔺 DISCLAIMER: The article is for information sharing. The content of this video is solely the opinions of the speaker who is not a licensed financial advisor or registered investment advisor. Not investment advice or legal advice.
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Thanks for visiting and watching! Please don’t forget to leave a like, comment and share!

#bitcoin #blockchain #bitcoin cash #what is bitcoin cash? - a beginner’s guide #what is bitcoin cash #a beginner’s guide

Jenkins Is Getting Old — It’s Time to Move On

By far, Jenkins is the most adopted tool for continuous integration, owning nearly 50% of the market share. As so many developers are using it, it has excellent community support, like no other Jenkins alternative. With that, it has more than 1,500 plugins available for continuous integration and delivery purposes.

We love and respect Jenkins. After all, it’s the first tool we encountered at the beginning of our automation careers. But as things are rapidly changing in the automation field, Jenkins is** left behind with his old approach**. Even though many developers and companies are using it, most of them aren’t happy with it. Having used it ourselves on previous projects, we quickly became frustrated by its lack of functionality, numerous maintenance issues, dependencies, and scaling problems.

We decided to investigate if other developers face the same problems and quickly saw the need to create a tool ourselves. We asked some developers at last year’s AWS Summit in Berlin about this. Most of them told us that they chose Jenkins because it’s free in the first place. However, many of them expressed interest in trying to use some other Jenkins alternative.

#devops #continuous integration #jenkins #devops adoption #jenkins ci #jenkins pipeline #devops continuous integration #jenkins automation #jenkins scripts #old technology

Jenkins Cheat Sheet – A Beginner’s Guide to Jenkins

A handy Jenkins cheat sheet which covers the basics of Jenkins along with the best practices that are needed for software development.

Are you a DevOps Enthusiast looking to explore different tools? If yes, then you have landed at the right place. DevOps Engineers are the most demanded and payed professionals all around the world. With this in mind let me introduce you to the most popular DevOps Tool, Jenkins. This Jenkins cheat sheet is for beginners who have prior knowledge about how a software development process occurs.

Jenkins Cheat Sheet

Continuous Integration is a software development practice in which developers are required to frequently commit changes to the source code in a shared repository. Each commit is then continuously pulled & built. Jenkins is an open source, Continuous Integration (CI) tool, written in Java. It continuously pulls, builds and tests any code commits made by a developer with the help of plugins.

Installation

Let’s start by installing Jenkins. This installation is specific to systems operating on Ubuntu. Follow the below steps:

Step 1: Install Java
$ sudo apt update
$ sudo apt install openjdk-8-jdk

Step 2: Add Jenkins Repository
$ wget -q -O - https://pkg.jenkins.io/debian/jenkins.io.key | sudo apt-key add –

Step 3: Add Jenkins repo to the system
$ sudo sh -c 'echo deb http://pkg.jenkins.io/debian-stable binary/ > /etc/apt/sources.list.d/jenkins.list'

Step 4: Install Jenkins
$ sudo apt update
$ sudo apt install Jenkins

Step 5: Verify installation
$ systemctl status Jenkins

Step 6: Once Jenkins is up and running, access it from the link:
http://localhost:8080

Most commonly used Jenkins Plugins

Jenkins comes with over 2000 plugins and each plugin has a unique functionality. But when it comes to software development most developers use a set of plugins, such as

• Maven
• Git
• Ant
• Docker
• Amazon EC2
• HTML publisher
• Copy artifact

Follow the below step to install the above plugins or any other Jenkins plugin.

Jenkins Dashboard -> Manage Jenkins -> Manage Plugins -> Available  

In the filter text field enter the name of the plugin you want to install.

Different Types of Jenkins Jobs

Jenkins provides the option of choosing from different types of jobs to build your project.

Below are the types of jobs you can choose from:

• Freestyle

Freestyle build jobs are general-purpose build jobs, which provides maximum flexibility. It can be used for any type of project.

• Pipeline

This project runs the entire software development workflow as code. Instead of creating several jobs for each stage of software development, you can now run the entire workflow as one code.

• Multiconfiguration

The multiconfiguration project allows you to run the same build job on different environments. It is used for testing an application in different environments.

• Folder

This project allows users to create folders to organize and categorize similar jobs in one folder or sub folder.

• GitHub Organization

This project scans your entire GitHub organization and creates Pipeline jobs for each repository containing a Jenkinsfile

• Multibranch pipeline

This project type lets you implement different Jenkinsfiles for different branches of the same project.

Build Pipeline

Build pipeline can be used to chain several jobs together and run them in a sequence. Let’s see how to install Build Pipeline:

Jenkins Dashboard -> Manage Jenkins -> Manage Plugins -> Available  

In the filter text field enter the name of the plugin you want to install.

Build Pipeline Example

Step 1: Create 3 freestyle Jobs (Job1, Job2, Job3)

Step 2: Chain the 3 Jobs together
Job1 -> configure -> Post Build -> Build other projects -> Job2
Job2 -> configure -> Post Build -> Build other projects -> Job3

Step 3: Create a build pipeline view
Jenkins Dashboard -> Add view -> Enter a name -> Build pipeline view -> ok ->
configure -> Pipeline flow -> Select Initial job -> Job1 -> ok

Step 4: Run the Build Pipeline

Jenkins Pipeline

Jenkins pipeline is a single platform that runs the entire _pipeline as code. _Instead of building several jobs for each phase, you can now code the entire workflow and put it in a Jenkinsfile.

Jenkinsfile is a text file that stores the pipeline as code. It is written using the Groovy DSL_. _It can be written based on two syntaxes:

• Scripted pipeline

Code is written on the Jenkins UI instance and is enclosed within the node block

node {
      scripted pipeline code
}

• Declarative pipeline

Code is written locally in a file and is checked into a SCM and is enclosed within the pipeline block

pipeline {
      declarative pipeline code
}

Pipeline Concepts

The below fundamentals are common to both, scripted and declarative pipeline:

1. Pipeline: A user defined block which contains all the stages. It is a key part of declarative pipeline syntax.

2. Node: A node is a machine that executes an entire workflow. It is a key part of the scripted pipeline syntax.

3. Agent: instructs Jenkins to allocate an executor for the builds. It is defined for an entire pipeline or a specific stage.

   It has the following parameters:

• Any: Runs pipeline/ stage on any available agent
• None: applied at the root of the pipeline, it indicates that there is no global agent for the entire pipeline & each stage must specify its own agent
• Label: Executes the pipeline/stage on the labelled agent.
• Docker: Uses docker container as an execution environment for the pipeline or a specific stage.

1. Stages: It contains all the work; each stage performs a specific task.
2. Steps: steps are carried out in sequence to execute a stage

Create your first Jenkins Pipeline

After installing Jenkins, building jobs using the Build pipeline and briefly discussing about pipeline concepts, let’s see how to create a Jenkins pipeline.

Follow the below steps to create both, a scripted pipeline and a declarative pipeline:

Jenkins Pipeline syntax example

Step 1: Log into Jenkins and select ‘New Item from the Dashboard'

Step 2: Next, enter a name for your pipeline and select ‘Pipeline project’. Click ‘ok’ to proceed

Step 3: Scroll down to the pipeline and choose if you want a Declarative or Scripted pipeline

Step 4a: If you want a Scripted pipeline, then choose ‘pipeline script’ and start typing your code

Step 4b: If you want a Declarative Pipeline, select ‘Pipeline script from SCM’ and choose your SCM and enter your repository URL

Step 5: Within the Script path is the name of the Jenkinsfile that is going to be accessed from your SCM to run. Finally click on ‘apply’ and ‘save’
node {
     stage(‘SCM checkout’) {
          //Checkout from your SCM(Source Control Management)
          //For eg: Git Checkout
     }
     stage(‘Build’) {
          //Compile code
          //Install dependencies
          //Perform Unit Test, Integration Test
     }
     stage(‘Test’) {
          //Resolve test server dependencies
          //Perform UAT
     }
     stage(‘Deploy’) {
          //Deploy code to prod server
          //Solve dependency issues
     }
}

Jenkins Tips and Tricks

Start, stop and restart Jenkins

Follow the below command to start, stop and restart Jenkins through the CLI.

$ sudo service jenkins restart
$ sudo service jenkins stop
$ sudo service jenkins start

Deploy a custom build of a core plugin

Step 1: Stop Jenkins.

Step 2: Copy the custom HPI to $Jenkins_Home/plugins.

Step 3: Delete the previously expanded plugin directory.

Step 4: Make an empty file called <plugin>.hpi.pinned.

Step 5: Start Jenkins.

Schedule a build periodically

Jenkins uses a cron expressions to schedule a job. Each line consists of 5 fields separated by TAB or whitespace:

Syntax: (Minute Hour DOM Month DOW)

MINUTE: Minutes in one hour (0-59)

HOURS: Hours in one day (0-23)

DAYMONTH: Day in a month (1-31)

MONTH: Month in a year (1-12)

DAYWEEK: Day of the week (0-7) where 0 and 7 are sunday

Example: H/2 * * * * (schedule your build for every 2 minutes)

Try this example:

H/2 * * * * (schedules your build for every 2 minutes)

Snippet Generator

A tool that lets users generate code for individual steps in a scripted pipeline. Let’s look at an example:

Step 1: Create a pipeline job > configure

Step 2: Select pipeline script from pipeline definition

Step 3: Click on Pipeline syntax > snippet generator

Step 4: Step > select Git > enter repo URL

Step 5: Scroll down > Generate pipeline script

Step 6: Copy the script into your pipeline script UI

Below is an image of the Snippet Generator. You can select from a variety of steps and generate a code for each step.

Below is an image of the Scripted pipeline UI with the code generated from snippet generator

Download Jenkins Cheat Sheet Edureka

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A Beginner’s Guide to Setting Up a Web Application with Typescript and Express

Web applications are types of software applications that run on remote servers (source). Examples of web applications can range from word processors, to file scanners, video editing tools, shopping carts, and more. Web applications can be great additions to any website; they can even function as websites themselves (Facebook, Gmail, and Udacity’s classroom are all examples of popular web applications), so understanding how to set up and implement a web application is a fantastic skill to have.

For this guide, I am assuming that you already have a basic knowledge of npm, node and whatExpress Requests and Responses are (or that you at least know what they are used for in their basic sense). Also, I assume that you know what the npm install and mkdir commands do. You have to know basic Typescript to implement — or at least know basic JavaScript to read and understand — the code below. Finally, this is the base for the backend of a web application. You still need to create a frontend application using a framework like Angular or an HTML/CSS file to make requests and display responses.

Before you start, it’s important that you create a folder in your favorite place on your computer. This can be anywhere as long as you have a sense of how you are going to find it later when you come up with an awesome project to start developing.

The Process:

#web-development #backend #software-development #beginners-guide #beginner