NOTE: V3 is out, please read the releases for all the (breaking)changes
NOTE for Windows users!!
Please check the FAQ
Date: 8th of May I decided to stop maintaining this package per today and add the DEPRECATED status to all versions Date: 16th of January 2020
I will stop maintaining this module per the first of July 2020. If you look at Protractor you can get the feeling that, in spite of all the effort that the Open Source Community is putting in it, it is not being maintained by Google anymore. To be honest, I'm pretty sure about it. If you look at the facts, see image below, you will notice that:
- the amount of issues is increasing
- the amount of PR's is increasing
- the activity in the project is decreasing
This is not giving me a good feeling. As a contributor to the Protractor project in the last years, I also have the feeling that there won't be a big chance that this is going to change.
I'm not the only one who thinks about Protractor like this, please take a look at this great article which might also give you some insights.
I want to thank all contributors for their help in the past 3-4 years and I feel blessed that I was able to help so many people over the last few years.
protractor-image-comparison is a lightweight protractor plugin for browsers / mobile browsers / hybrid apps to do image comparison on screens, elements or full page screens.
You can:
- save or compare screens / elements / full page screens against a baseline
- automatically create a baseline when no baseline is there
- blockout custom regions and even automatically exclude a status and or tool bars (mobile only) during a comparison
- hide / remove elements during comparison like for example stickyheaders (NEW)
- increase the element dimensions screenshots
- use different comparison methods
- and much more, see the options here
The module is now based on the power of the new webdriver-image-comparison
module. This is a lightweight module to retrieve the needed data and screenshots for all browsers / devices.
The comparison power comes from ResembleJS. If you want to compare images online you can check the online tool
It can be used for:
- desktop browsers (Chrome / Firefox / Safari / Internet Explorer 11 / Microsoft Edge)
- mobile / tablet browsers (Chrome / Safari on emulators / real devices) via Appium
- Hybrid apps via Appium
NOTE: See the browser-matrix at the top of this readme to see all the supported browser/OS-versions.
Install this module locally with the following command to be used as a (dev-)dependency:
npm install --save protractor-image-comparison
npm install --save-dev protractor-image-comparison
protractor-image-comparison supports NodeJS 8 or higher
In comparison to versions < 3 protractor-image-comparison can now be used as a plugin with the following code:
// protractor.conf.js
const { join } = require('path');
exports.config = {
// ... the rest of your config
plugins: [
{
// The module name
package: 'protractor-image-comparison',
// Some options, see the docs for more
options: {
baselineFolder: join(process.cwd(), './baseline/'),
formatImageName: `{tag}-{logName}-{width}x{height}`,
screenshotPath: join(process.cwd(), '.tmp/'),
savePerInstance: true,
// ... more options
},
},
],
};
More plugin options can be found here.
protractor-image-comparison is framework agnostic, meaning that you can use it with all the frameworks Protractor supports like Jasmine|Mocha|CucumberJS
.
You can use it like this:
import {$, browser} from 'protractor';
describe('protractor-image-comparison desktop', () => {
beforeEach(async () => {
await browser.get(browser.baseUrl);
});
it('should save some screenshots', async() => {
// Save a screen
await browser.imageComparison.saveScreen('examplePaged', { /* some options*/ });
// Save an element
await browser.imageComparison.saveElement($('.uk-button:nth-child(1)'), 'firstButtonElement', { /* some options*/ });
// Save a full page screens
await browser.imageComparison.saveFullPageScreen('fullPage', { /* some options*/ });
});
it('should compare successful with a baseline', async() => {
// Check a screen
expect(await browser.imageComparison.checkScreen('examplePaged', { /* some options*/ })).toEqual(0);
// Check an element
expect(await browser.imageComparison.checkElement($('.uk-button:nth-child(1)'), 'firstButtonElement', { /* some options*/ })).toEqual(0);
// Check a full page screens
expect(await browser.imageComparison.checkFullPageScreen('fullPage', { /* some options*/ })).toEqual(0);
});
});
If you run for the first time without having a baseline the check
-methods will reject the promise with the following warning:
#####################################################################################
Baseline image not found, save the actual image manually to the baseline.
The image can be found here:
/Users/wswebcreation/Git/protractor-image-comparison/.tmp/actual/desktop_chrome/examplePage-chrome-latest-1366x768.png
If you want the module to auto save a non existing image to the baseline you
can provide 'autoSaveBaseline: true' to the options.
#####################################################################################
This means that the current screenshot is saved in the actual folder and you manually need to copy it to your baseline.
If you instantiate protractor-image-comparsion
with autoSaveBaseline: true
the image will automatically be saved into the baseline folder.
The save(Screen/Element/FullPageScreen)
methods will provide the following information after the method has been executed:
const saveResult = {
// The device pixel ratio of the instance that has run
devicePixelRatio: 1,
// The formatted filename, this depends on the options `formatImageName`
fileName: 'examplePage-chrome-latest-1366x768.png',
// The path where the actual screenshot file can be found
path: '/Users/wswebcreation/Git/protractor-image-comparison/.tmp/actual/desktop_chrome',
};
See the Check output on failure section in the output docs for the images.
By default the check(Screen/Element/FullPageScreen)
methods will only provide a mismatch percentage like 1.23
, but when the plugin has the options returnAllCompareData: true
the following information is provided after the method has been executed:
const checkResult = {
// The formatted filename, this depends on the options `formatImageName`
fileName: 'examplePage-chrome-headless-latest-1366x768.png',
folders: {
// The actual folder and the file name
actual: '/Users/wswebcreation/Git/protractor-image-comparison/.tmp/actual/desktop_chrome/examplePage-chrome-headless-latest-1366x768.png',
// The baseline folder and the file name
baseline: '/Users/wswebcreation/Git/protractor-image-comparison/localBaseline/desktop_chrome/examplePage-chrome-headless-latest-1366x768.png',
// This following folder is optional and only if there is a mismatch
// The folder that holds the diffs and the file name
diff: '/Users/wswebcreation/Git/protractor-image-comparison/.tmp/diff/desktop_chrome/examplePage-chrome-headless-latest-1366x768.png',
},
// The mismatch percentage
misMatchPercentage: 2.34
};
See the Save output section in the output docs for the images.
Do I need to use a save(Screen/Element/FullPageScreen)
methods when I want to run check(Screen/Element/FullPageScreen)
?
No, you don't need to do this. The check(Screen/Element/FullPageScreen)
will do this automatically for you
It could be that the error Width and height cannot be negative
is thrown. 9 out of 10 times this is related to creating an image of an element that is not in the view. Please be sure you always make sure the element in is in the view before you try to make an image of the element.
When using Chrome and using the chromeOptions.args:['--disable-gpu']
it could be possible that the images can't be compared in the correct way. If you remove this argument all will work again. See here
See CONTRIBUTING.md.
- iOS Safari on iPads can have multiple tabs, so the address bar is bigger making the cutout go wrong
- create a new website
protractor-image-comparison
uses an open source licence from Sauce Labs.
You can request your open source licence here