Lia  Haley

Lia Haley

1598436960

5 Puppeteer Tricks That Will Make Your Web Scraping Easier

Puppeteer probably is the best free web scraping tool on the internet. It has so many options and is very easy to use once you get the hang of it. The problem with it is that it is too complicated and the average developer might be overwhelmed by the vast options it offers.

As a veteran in the web scraping industry and the proxy world, I’ve gathered five puppeteer tricks (with code examples), which I believe help you with the daunting task of web scraping when using Puppeteer and how they will help you avoid detection.

So, What is Puppeteer?

Puppeteer is an open-source Node.js library developed and maintained by Google. It is based on Chromium, the open version of Chrome, and can do almost any task a human can perform on a regular web browser. It has a headless mode, which allows it to run as code in the background, without actually rendering the pages, and thus reduces a lot of the resources needed to run it.

Google’s maintenance of this library is fantastic, with new features and security updates regularly added a clear and easy-to-use API, and user-friendly documentation.

What is Web Scraping?

Web Scraping is the automatic version of surfing the web and collecting data. The internet is full of content and user-generated content (UGC), so you can scrape countless data points.

However, most of the valuable data is in these popular websites, which are being scraped daily are Google search results, eCommerce platforms like Amazon, Walmart, Shopify, Travel websites, hotels you get the deal. Most companies or individuals who perform web scraping are looking for data to improve their sales, search rankings, keyword analysis, price comparison, and so on.

What Is the Difference Between Web Crawling and Web Scraping?

Web scraping and web crawling are very similar terms, and the confusion between them is natural. The main difference between web scraping and web crawling revolves around the type of operation/activity that the user is doing.

Web crawling moves around a website and collects links, and optionally goes through those links and collects and aggregates data or additional links. It is called crawling because it works like a spider that crawls through a website; this is why crawlers are often called spiders by some developers.

Web Scraping on the other hand is task-oriented. It’s targeting a predefined link and retrieves the data from it and sends it to the database.

Usually, a data collection is built around a combination of those two approaches, which means getting the links to scrape with a web crawler/spider and then scraping the data from those pages with a scraper.

#web scraping #puppeteer #web crawling web scraping

What is GEEK

Buddha Community

5 Puppeteer Tricks That Will Make Your Web Scraping Easier
Lia  Haley

Lia Haley

1598436960

5 Puppeteer Tricks That Will Make Your Web Scraping Easier

Puppeteer probably is the best free web scraping tool on the internet. It has so many options and is very easy to use once you get the hang of it. The problem with it is that it is too complicated and the average developer might be overwhelmed by the vast options it offers.

As a veteran in the web scraping industry and the proxy world, I’ve gathered five puppeteer tricks (with code examples), which I believe help you with the daunting task of web scraping when using Puppeteer and how they will help you avoid detection.

So, What is Puppeteer?

Puppeteer is an open-source Node.js library developed and maintained by Google. It is based on Chromium, the open version of Chrome, and can do almost any task a human can perform on a regular web browser. It has a headless mode, which allows it to run as code in the background, without actually rendering the pages, and thus reduces a lot of the resources needed to run it.

Google’s maintenance of this library is fantastic, with new features and security updates regularly added a clear and easy-to-use API, and user-friendly documentation.

What is Web Scraping?

Web Scraping is the automatic version of surfing the web and collecting data. The internet is full of content and user-generated content (UGC), so you can scrape countless data points.

However, most of the valuable data is in these popular websites, which are being scraped daily are Google search results, eCommerce platforms like Amazon, Walmart, Shopify, Travel websites, hotels you get the deal. Most companies or individuals who perform web scraping are looking for data to improve their sales, search rankings, keyword analysis, price comparison, and so on.

What Is the Difference Between Web Crawling and Web Scraping?

Web scraping and web crawling are very similar terms, and the confusion between them is natural. The main difference between web scraping and web crawling revolves around the type of operation/activity that the user is doing.

Web crawling moves around a website and collects links, and optionally goes through those links and collects and aggregates data or additional links. It is called crawling because it works like a spider that crawls through a website; this is why crawlers are often called spiders by some developers.

Web Scraping on the other hand is task-oriented. It’s targeting a predefined link and retrieves the data from it and sends it to the database.

Usually, a data collection is built around a combination of those two approaches, which means getting the links to scrape with a web crawler/spider and then scraping the data from those pages with a scraper.

#web scraping #puppeteer #web crawling web scraping

Osiki  Douglas

Osiki Douglas

1624595434

How POST Requests with Python Make Web Scraping Easier

When scraping a website with Python, it’s common to use the

urllibor theRequestslibraries to sendGETrequests to the server in order to receive its information.

However, you’ll eventually need to send some information to the website yourself before receiving the data you want, maybe because it’s necessary to perform a log-in or to interact somehow with the page.

To execute such interactions, Selenium is a frequently used tool. However, it also comes with some downsides as it’s a bit slow and can also be quite unstable sometimes. The alternative is to send a

POSTrequest containing the information the website needs using the request library.

In fact, when compared to Requests, Selenium becomes a very slow approach since it does the entire work of actually opening your browser to navigate through the websites you’ll collect data from. Of course, depending on the problem, you’ll eventually need to use it, but for some other situations, a

POSTrequest may be your best option, which makes it an important tool for your web scraping toolbox.

In this article, we’ll see a brief introduction to the

POSTmethod and how it can be implemented to improve your web scraping routines.

#python #web-scraping #requests #web-scraping-with-python #data-science #data-collection #python-tutorials #data-scraping

Autumn  Blick

Autumn Blick

1603805749

What's the Link Between Web Automation and Web Proxies?

Web automation and web scraping are quite popular among people out there. That’s mainly because people tend to use web scraping and other similar automation technologies to grab information they want from the internet. The internet can be considered as one of the biggest sources of information. If we can use that wisely, we will be able to scrape lots of important facts. However, it is important for us to use appropriate methodologies to get the most out of web scraping. That’s where proxies come into play.

How Can Proxies Help You With Web Scraping?

When you are scraping the internet, you will have to go through lots of information available out there. Going through all the information is never an easy thing to do. You will have to deal with numerous struggles while you are going through the information available. Even if you can use tools to automate the task and overcome struggles, you will still have to invest a lot of time in it.

When you are using proxies, you will be able to crawl through multiple websites faster. This is a reliable method to go ahead with web crawling as well and there is no need to worry too much about the results that you are getting out of it.

Another great thing about proxies is that they will provide you with the chance to mimic that you are from different geographical locations around the world. While keeping that in mind, you will be able to proceed with using the proxy, where you can submit requests that are from different geographical regions. If you are keen to find geographically related information from the internet, you should be using this method. For example, numerous retailers and business owners tend to use this method in order to get a better understanding of local competition and the local customer base that they have.

If you want to try out the benefits that come along with web automation, you can use a free web proxy. You will be able to start experiencing all the amazing benefits that come along with it. Along with that, you will even receive the motivation to take your automation campaigns to the next level.

#automation #web #proxy #web-automation #web-scraping #using-proxies #website-scraping #website-scraping-tools

Ray  Patel

Ray Patel

1619518440

top 30 Python Tips and Tricks for Beginners

Welcome to my Blog , In this article, you are going to learn the top 10 python tips and tricks.

1) swap two numbers.

2) Reversing a string in Python.

3) Create a single string from all the elements in list.

4) Chaining Of Comparison Operators.

5) Print The File Path Of Imported Modules.

6) Return Multiple Values From Functions.

7) Find The Most Frequent Value In A List.

8) Check The Memory Usage Of An Object.

#python #python hacks tricks #python learning tips #python programming tricks #python tips #python tips and tricks #python tips and tricks advanced #python tips and tricks for beginners #python tips tricks and techniques #python tutorial #tips and tricks in python #tips to learn python #top 30 python tips and tricks for beginners

Annie  Emard

Annie Emard

1653075360

HAML Lint: Tool For Writing Clean and Consistent HAML

HAML-Lint

haml-lint is a tool to help keep your HAML files clean and readable. In addition to HAML-specific style and lint checks, it integrates with RuboCop to bring its powerful static analysis tools to your HAML documents.

You can run haml-lint manually from the command line, or integrate it into your SCM hooks.

Requirements

  • Ruby 2.4+
  • HAML 4.0+

Installation

gem install haml_lint

If you'd rather install haml-lint using bundler, don't require it in your Gemfile:

gem 'haml_lint', require: false

Then you can still use haml-lint from the command line, but its source code won't be auto-loaded inside your application.

Usage

Run haml-lint from the command line by passing in a directory (or multiple directories) to recursively scan:

haml-lint app/views/

You can also specify a list of files explicitly:

haml-lint app/**/*.html.haml

haml-lint will output any problems with your HAML, including the offending filename and line number.

File Encoding

haml-lint assumes all files are encoded in UTF-8.

Command Line Flags

Command Line FlagDescription
--auto-gen-configGenerate a configuration file acting as a TODO list
--auto-gen-exclude-limitNumber of failures to allow in the TODO list before the entire rule is excluded
-c/--configSpecify which configuration file to use
-e/--excludeExclude one or more files from being linted
-i/--include-linterSpecify which linters you specifically want to run
-x/--exclude-linterSpecify which linters you don't want to run
-r/--reporterSpecify which reporter you want to use to generate the output
-p/--parallelRun linters in parallel using available CPUs
--fail-fastSpecify whether to fail after the first file with lint
--fail-levelSpecify the minimum severity (warning or error) for which the lint should fail
--[no-]colorWhether to output in color
--[no-]summaryWhether to output a summary in the default reporter
--show-lintersShow all registered linters
--show-reportersDisplay available reporters
-h/--helpShow command line flag documentation
-v/--versionShow haml-lint version
-V/--verbose-versionShow haml-lint, haml, and ruby version information

Configuration

haml-lint will automatically recognize and load any file with the name .haml-lint.yml as a configuration file. It loads the configuration based on the directory haml-lint is being run from, ascending until a configuration file is found. Any configuration loaded is automatically merged with the default configuration (see config/default.yml).

Here's an example configuration file:

linters:
  ImplicitDiv:
    enabled: false
    severity: error

  LineLength:
    max: 100

All linters have an enabled option which can be true or false, which controls whether the linter is run, along with linter-specific options. The defaults are defined in config/default.yml.

Linter Options

OptionDescription
enabledIf false, this linter will never be run. This takes precedence over any other option.
includeList of files or glob patterns to scope this linter to. This narrows down any files specified via the command line.
excludeList of files or glob patterns to exclude from this linter. This excludes any files specified via the command line or already filtered via the include option.
severityThe severity of the linter. External tools consuming haml-lint output can use this to determine whether to warn or error based on the lints reported.

Global File Exclusion

The exclude global configuration option allows you to specify a list of files or glob patterns to exclude from all linters. This is useful for ignoring third-party code that you don't maintain or care to lint. You can specify a single string or a list of strings for this option.

Skipping Frontmatter

Some static blog generators such as Jekyll include leading frontmatter to the template for their own tracking purposes. haml-lint allows you to ignore these headers by specifying the skip_frontmatter option in your .haml-lint.yml configuration:

skip_frontmatter: true

Inheriting from Other Configuration Files

The inherits_from global configuration option allows you to specify an inheritance chain for a configuration file. It accepts either a scalar value of a single file name or a vector of multiple files to inherit from. The inherited files are resolved in a first in, first out order and with "last one wins" precedence. For example:

inherits_from:
  - .shared_haml-lint.yml
  - .personal_haml-lint.yml

First, the default configuration is loaded. Then the .shared_haml-lint.yml configuration is loaded, followed by .personal_haml-lint.yml. Each of these overwrite each other in the event of a collision in configuration value. Once the inheritance chain is resolved, the base configuration is loaded and applies its rules to overwrite any in the intermediate configuration.

Lastly, in order to match your RuboCop configuration style, you can also use the inherit_from directive, which is an alias for inherits_from.

Linters

» Linters Documentation

haml-lint is an opinionated tool that helps you enforce a consistent style in your HAML files. As an opinionated tool, we've had to make calls about what we think are the "best" style conventions, even when there are often reasonable arguments for more than one possible style. While all of our choices have a rational basis, we think that the opinions themselves are less important than the fact that haml-lint provides us with an automated and low-cost means of enforcing consistency.

Custom Linters

Add the following to your configuration file:

require:
  - './relative/path/to/my_first_linter.rb'
  - 'absolute/path/to/my_second_linter.rb'

The files that are referenced by this config should have the following structure:

module HamlLint
  # MyFirstLinter is the name of the linter in this example, but it can be anything
  class Linter::MyFirstLinter < Linter
    include LinterRegistry

    def visit_tag
      return unless node.tag_name == 'div'
      record_lint(node, "You're not allowed divs!")
    end
  end
end

For more information on the different types on HAML node, please look through the HAML parser code: https://github.com/haml/haml/blob/master/lib/haml/parser.rb

Keep in mind that by default your linter will be disabled by default. So you will need to enable it in your configuration file to have it run.

Disabling Linters within Source Code

One or more individual linters can be disabled locally in a file by adding a directive comment. These comments look like the following:

-# haml-lint:disable AltText, LineLength
[...]
-# haml-lint:enable AltText, LineLength

You can disable all linters for a section with the following:

-# haml-lint:disable all

Directive Scope

A directive will disable the given linters for the scope of the block. This scope is inherited by child elements and sibling elements that come after the comment. For example:

-# haml-lint:disable AltText
#content
  %img#will-not-show-lint-1{ src: "will-not-show-lint-1.png" }
  -# haml-lint:enable AltText
  %img#will-show-lint-1{ src: "will-show-lint-1.png" }
  .sidebar
    %img#will-show-lint-2{ src: "will-show-lint-2.png" }
%img#will-not-show-lint-2{ src: "will-not-show-lint-2.png" }

The #will-not-show-lint-1 image on line 2 will not raise an AltText lint because of the directive on line 1. Since that directive is at the top level of the tree, it applies everywhere.

However, on line 4, the directive enables the AltText linter for the remainder of the #content element's content. This means that the #will-show-lint-1 image on line 5 will raise an AltText lint because it is a sibling of the enabling directive that appears later in the #content element. Likewise, the #will-show-lint-2 image on line 7 will raise an AltText lint because it is a child of a sibling of the enabling directive.

Lastly, the #will-not-show-lint-2 image on line 8 will not raise an AltText lint because the enabling directive on line 4 exists in a separate element and is not a sibling of the it.

Directive Precedence

If there are multiple directives for the same linter in an element, the last directive wins. For example:

-# haml-lint:enable AltText
%p Hello, world!
-# haml-lint:disable AltText
%img#will-not-show-lint{ src: "will-not-show-lint.png" }

There are two conflicting directives for the AltText linter. The first one enables it, but the second one disables it. Since the disable directive came later, the #will-not-show-lint element will not raise an AltText lint.

You can use this functionality to selectively enable directives within a file by first using the haml-lint:disable all directive to disable all linters in the file, then selectively using haml-lint:enable to enable linters one at a time.

Onboarding Onto a Preexisting Project

Adding a new linter into a project that wasn't previously using one can be a daunting task. To help ease the pain of starting to use Haml-Lint, you can generate a configuration file that will exclude all linters from reporting lint in files that currently have lint. This gives you something similar to a to-do list where the violations that you had when you started using Haml-Lint are listed for you to whittle away, but ensuring that any views you create going forward are properly linted.

To use this functionality, call Haml-Lint like:

haml-lint --auto-gen-config

This will generate a .haml-lint_todo.yml file that contains all existing lint as exclusions. You can then add inherits_from: .haml-lint_todo.yml to your .haml-lint.yml configuration file to ensure these exclusions are used whenever you call haml-lint.

By default, any rules with more than 15 violations will be disabled in the todo-file. You can increase this limit with the auto-gen-exclude-limit option:

haml-lint --auto-gen-config --auto-gen-exclude-limit 100

Editor Integration

Vim

If you use vim, you can have haml-lint automatically run against your HAML files after saving by using the Syntastic plugin. If you already have the plugin, just add let g:syntastic_haml_checkers = ['haml_lint'] to your .vimrc.

Vim 8 / Neovim

If you use vim 8+ or Neovim, you can have haml-lint automatically run against your HAML files as you type by using the Asynchronous Lint Engine (ALE) plugin. ALE will automatically lint your HAML files if it detects haml-lint in your PATH.

Sublime Text 3

If you use SublimeLinter 3 with Sublime Text 3 you can install the SublimeLinter-haml-lint plugin using Package Control.

Atom

If you use atom, you can install the linter-haml plugin.

TextMate 2

If you use TextMate 2, you can install the Haml-Lint.tmbundle bundle.

Visual Studio Code

If you use Visual Studio Code, you can install the Haml Lint extension

Git Integration

If you'd like to integrate haml-lint into your Git workflow, check out our Git hook manager, overcommit.

Rake Integration

To execute haml-lint via a Rake task, make sure you have rake included in your gem path (e.g. via Gemfile) add the following to your Rakefile:

require 'haml_lint/rake_task'

HamlLint::RakeTask.new

By default, when you execute rake haml_lint, the above configuration is equivalent to running haml-lint ., which will lint all .haml files in the current directory and its descendants.

You can customize your task by writing:

require 'haml_lint/rake_task'

HamlLint::RakeTask.new do |t|
  t.config = 'custom/config.yml'
  t.files = ['app/views', 'custom/*.haml']
  t.quiet = true # Don't display output from haml-lint to STDOUT
end

You can also use this custom configuration with a set of files specified via the command line:

# Single quotes prevent shell glob expansion
rake 'haml_lint[app/views, custom/*.haml]'

Files specified in this manner take precedence over the task's files attribute.

Documentation

Code documentation is generated with YARD and hosted by RubyDoc.info.

Contributing

We love getting feedback with or without pull requests. If you do add a new feature, please add tests so that we can avoid breaking it in the future.

Speaking of tests, we use Appraisal to test against both HAML 4 and 5. We use rspec to write our tests. To run the test suite, execute the following from the root directory of the repository:

appraisal bundle install
appraisal bundle exec rspec

Community

All major discussion surrounding HAML-Lint happens on the GitHub issues page.

Changelog

If you're interested in seeing the changes and bug fixes between each version of haml-lint, read the HAML-Lint Changelog.

Author: sds
Source Code: https://github.com/sds/haml-lint
License: MIT license

#haml #lint