JLineup is a tool which is useful for automated visual regression tests of web pages, especially in continuous delivery pipelines. It can be used as a simple command line tool or as a small web service which is controlled via REST API.
JLineup shoots and compares screenshots of a web page at two consecutive points in time. It does a pixel by pixel comparison of both runs and generates a HTML and a JSON report. Behind the scenes, it uses Selenium and a browser of choice (currently Chrome, Firefox and PhantomJS¹ are supported).
JLineup has no other dependencies than web browser (Firefox or Chrome/Chromium) and a JVM. Experimental: There's also a self contained Linux AMD64 build of the CLI version that doesn't even require a JVM.
Let's take this little example config for a check of two paths on otto.de during a deployment:
{
"urls": {
"https://www.otto.de": {
"paths": [
"/wohnen/?thema=thmn123nol_retro_chic",
"/k/10072934231?a=224673"
],
"window-widths": [ 500,1000,1200,1600 ]
}
},
"wait-after-page-load" : 3,
"window-height" : 800,
"browser" : "chrome-headless"
}
JLineup runs before and after the deployment and generates a report like this:
There's also a JSON report, which is great if you want to check things by script:
JLineup CLI comes as executable Java Archive. Java 8 or higher has to be available to run it.
Open a terminal and download it like this:
wget https://repo1.maven.org/maven2/de/otto/jlineup-cli/4.3.4/jlineup-cli-4.3.4.jar -O jlineup.jar
Then type
java -jar jlineup.jar --help
to see the command line help.
See the CLI documentation for more details and a small tutorial.
This is an example, how JLineup can be helpful in your automated build and deploy pipeline. Let's assume, this is part of a continuous integration pipeline:
JLineup 4.3.4 was tested successfully with
- Chrome 92.x
- Firefox 91.x
- PhantomJS 2.1.1 (auto-downloaded by JLineup if not installed)
Chrome or Firefox have to be installed on the system if you want to use one of them.
JLineup uses some third party tools and libraries
- Selenium is licensed under the Apache 2.0 License
- Webdrivermanager is licensed under the Apache 2.0 License
- Jackson is licensed under the Apache 2.0 License
- Logback is licensed under the Eclipse Public License
- The SLF4J API is licensed under the MIT License
- PhantomJS is licensed under the BSD-3-Clause
- Thymeleaf is licensed under the Apache 2.0 License
- Edison Microservice is licensed under the Apache 2.0 License
- Spring Boot is licensed under the Apache 2.0 License
- The binary cli version is built with GraalVM Community Edition. GraalVM CE brings it's own Product License.
JLineup is a configuration compatible replacement for Lineup, implemented in Java. The original Lineup was a Ruby tool, but is not maintained any more.
Credit for original Lineup goes to Finn Lorbeer.
If you have questions or proposals, please open an issue or write an email to marco DOT geweke AT otto.de
¹) PhantomJS Development has been suspended. For more details go to ariya/phantomjs#15344