PhantomJS Course And Certification
What is PhantomJS?
PhantomJS is assumed to be a headless web browser because it has no involvement with the browser while executing the client-side JavaScript code. The execution of the program will not be displayed in any browser window, but just on the command line prompt. The various functionalities like handling of CSS, JSON, Ajax, DOM Manipulation, SVG, Canvas, etc, will all be handled at the command prompt. PhantomJS does not come with a Graphical User Interface, therefore, all of its execution is being carried out at the command line.
By using PhantomJS, you can write to a file on your local system, read the contents of the file or upload a file to a web server, capture a screen, convert the webpage that you are loading into a pdf and a whole lot more. With headless browsers, you are provided with all the browser behavior, for example, Http Request Methods i.e. GET /POST, Cookies, Deleting Cookies, Clearing Cookies, Reloading of a web Page, Navigating to a Different Page, etc.
PhantomJS also makes use of WebKit which has a similar browsing environment like other popular browsers such as, Google Chrome, Safari, Mozilla Firefox, etc. PhantomJS also presents developers with a lot of JavaScript API, which helps in uploading a file, taking screenshots, writing to file, interacting with the web pages, reading a file, etc.
PhantomJS is a free software program that is distributed under the BSD License. It is very easy to install and it offers developers and web testers with multiple features run scripts. PhantomJS can be easily run on multiple platforms and Operating Systems such as Windows, Mac, and Linux.
Features of PhantomJS
Below are some of the features that PhantomJS offers.
1. Page Automation: PhantomJS allows you to read the contents of a web page with the help of its API. WIth PhantomJS, you can manipulate the DOM, and it presents you with a lot of external libraries to carry out the task required. Developers can write JavaScript code that will be evaluated against a specified page. Although this may not seem very important, this allows us to automate any sort of interactions with a web page without having to open a browser (an operation that will save you a tremendous amount of time).
2. Screen Capture: This utilizes WebKit, PhantomJS helps you with screen capturing of a specified web page and save the same as an image in several formats such as JPEG, PNG, PDF, and GIF. With the help of the screen capture, you can easily help make sure that the web content and its positioning are fine. Therefore, it can be used to automate the process of capturing screenshots of web pages that developers can analyze to ensure that everything looks good. PhantomJS also allows developers to adjust the size of these screenshots, and specify the exact areas that we want to capture.
3. Headless Testing: PhantomJS helps with the testing of UI at the command line. By making use of screenshots, you can easily find out errors in UI. PhantomJS in some cases, cannot help with testing alone. It helps developers to automate the process of running tests without a need for any sort of GUI. PhantomJS makes use of its headless browser to handle different unit tests instead and uses the command line to tell developers where they are running into an error. However, it can be wrapped together with other testing libraries like Yoeman, Mocha, etc. PhantomJS is also used in continuous integration systems. Continuous integration is a way to monitor your application. Developers can integrate PhantomJS with CI systems (such as Travis CI) in order to run tests on any new code being added to a project, before actually pushing the code. As a result, developers are able to detect problems in code as soon as they arise, and fix them, thus ensuring that no broken code will be pushed to the project.
4. Network Monitoring: One of the most important features of PhantomJS is it's being used to monitor the network connection by using the available API. PhantomJS allows for the inspection of network traffic; it is very fitting for building various analyses on network performance and behavior. PhantomJS can be used to collect data about the performance of the webpage in a live development environment. PhantomJS can be used with various tools like Yslow to gather the performance metrics of any websites. Additionally, PhantomJS and YSlow make use of TAP protocol in continuous integration systems and monitor the performance of the new code being added to a project. In this way, developers can be informed of any regression in performance before the code is pushed.
Benefits of PhantomJS
There are many benefits and advantages of PhantomJS and some of them are:
1. PhantomJS is a headless browser, and headless browsers are faster than real browsers.
2. PhantomJS is very popular and useful for web scraping.
3. PhantomJS saves you Development time, by eliminating the need to open web browsers and reloading along with other features
4. PhantomJS allows you to monitor the performance of a website with headless browser scripts
5. PhantonJS helps in the automation of Software Production.
Why Study PhantomJS?
1. Automate test from the command line
2. Detects errors in code
3. Interact with the browser from the command line
4. Job Opportunities And Career Advancement
5. Increase Your Earning Potential