Grab Screenshots

This is a collection of scripts for taking and comparing screenshots of WordPress admin pages. This is mostly a personal tool, where I create scripts to run through various pages while testing tickets.

Quickstart

cd grab-screenshots
npm install
npm run snap

Available scripts

The scripts use environment variables for configuration. Pass these in before the script command, ex:

WP_BASE_URL=http://localhost:8888 npm run snap

The following variables are used for index.js/npm run snap.

Env Variable	Default	Description
WP_USERNAME	admin	Username to log in with, should have access to all pages that are requested.
WP_PASSWORD	password	Password for account.
WP_BASE_URL	http://trunk.wordpress.test/	The URL to the running WordPress instance. Note, this does not have to be a local install.
IMAGE_PATH	screenshots	Where the screenshots will be saved. This directory needs to exist already.

index.js

Run this with npm run snap. It will loop over all core color schemes and take screenshots of an assortment of pages, sometimes with elements hovered or focused. Read through the script to see the steps it takes.

diff.js

Run this with npm run diff. Assuming you have two folders of matching screenshots, this will run blink-diff over each file-pair in the folders.

Env Variable	Default	Description
IMAGE_A_PATH	photos-a	First folder of screenshots.
IMAGE_B_PATH	photos-b	Second folder of screenshots.
DIFF_PATH	photos-diffs	Output folder for visual diffs.

Putting them together

If you want to check the difference between two branches of WordPress, you could…

1. Check out trunk and build.
2. Run the first screenshot grab.

   mkdir screenshots-trunk
   IMAGE_PATH=screenshots-trunk node index.js

3. Check out your branch and build.
4. Run the second screenshot grab.

   mkdir screenshots-branch
   IMAGE_PATH=screenshots-branch node index.js

5. Run the image comparison script with each folder.

   mkdir screenshots-diff
   IMAGE_A_PATH=screenshots-trunk IMAGE_B_PATH=screenshots-branch DIFF_PATH=screenshots-diff npm run diff

6. 🎉 You should now have a folder screenshots-diff with the differences highlighted.