Post Images from blocks: move from parse_blocks to Block_Delimiter

[jeherve]

Proposed changes:

Following #43648, we can start using the new class to parse blocks.

This should not change anything in the existing functionality, but should improve performance.

Performance-wise, there are gains when comparing the time to fetch images with the 2 methods, although they are minimal with this change alone.

For reference, measuring speed for a post based off this long post's contents, with added galleries, single images, slideshows, stories, tiled galleries, groups:

• Processing with Block delimiter took: 9.428 milliseconds
• Processing with parse_blocks took: 10.673 milliseconds

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

• Internal reference: p7H4VZ-5l1-p2

Does this pull request change what data or activity we track or use?

• No

Testing instructions:

• Start from a site using no other Open Graph / Sharing plugins
• Activate Jetpack's sharing module.
• Create a new post using the block editor.
• Do not specify any Featured image
• Do not upload any image to that post.
• Instead, insert a new image block and choose from an image you've already uploaded, for another post (this is so Jetpack_PostImages does not pick images from attachments to your post)
• Publish your post.
• View source when looking at the post.
  • You should see your image used in the Open Graph Meta tags.
• Repeat with an image that is smaller than the requirements (200x200):
  • it should not be picked.
• Repeat by inserting an image from another site, e.g. https://herve.bzh/wp-content/uploads/2013/01/watson-5818-1.jpg:
  • it should not be picked.
• Repeat by inserting a gallery block instead, with images originally uploaded to another post.
  • It should be able to pick images.
• Repeat by inserting a tiled gallery block instead, with images originally uploaded to another post.
  • It should be able to pick images.

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack), and enable the add/block-delimiter-post-iamges branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack add/block-delimiter-post-iamges

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

• ✅ Include a description of your PR changes.
  
• ✅ Add a "[Status]" label (In Progress, Needs Review, ...).
  
• ✅ Add a "[Type]" label (Bug, Enhancement, Janitorial, Task).
  
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• ✅ Specify whether this PR includes any changes to data or privacy.
  
• ✅ Add changelog entries to affected projects
  

This comment will be updated as you work on your PR and make changes. If you think that some of those checks are not needed for your PR, please explain why you think so. Thanks for cooperation 🤖

---

Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Make sure to test your changes on all platforms that it applies to. You're responsible for the quality of the code you ship.
3. You can use GitHub's Reviewers functionality to request a review.
4. When it's reviewed and merged, you will be pinged in Slack to deploy the changes to WordPress.com simple once the build is done.

If you have questions about anything, reach out in #jetpack-developers for guidance!

---

Jetpack plugin:

The Jetpack plugin has different release cadences depending on the platform:

• WordPress.com Simple releases happen as soon as you deploy your changes after merging this PR (PCYsg-Jjm-p2).
• WoA releases happen weekly.
• Releases to self-hosted sites happen monthly:
  • Scheduled release: June 3, 2025
  • Code freeze: June 2, 2025

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

[Copilot]

Pull Request Overview

This PR refactors the post image extraction to use the new Block_Delimiter class for parsing Gutenberg blocks, aiming for performance improvements without changing existing functionality.

• Adds automattic/block-delimiter as a dependency and updates composer.json
• Rewrites from_blocks() to scan with Block_Delimiter and introduces get_images_from_block_attributes()
• Removes the old recursive parse_blocks() logic and utility methods, and adds a changelog entry

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

File	Description
projects/plugins/jetpack/tests/php/media/Jetpack_PostImages_Test.php	Minor whitespace change in test imports
projects/plugins/jetpack/composer.json	Added automattic/block-delimiter dependency
projects/plugins/jetpack/class.jetpack-post-images.php	Refactored from_blocks() to use Block_Delimiter, removed old parsing logic, added get_images_from_block_attributes()
projects/plugins/jetpack/changelog/add-block-delimiter-post-iamges	New changelog entry for performance enhancement

Comments suppressed due to low confidence (2)

projects/plugins/jetpack/changelog/add-block-delimiter-post-iamges:0

• Rename the changelog file to add-block-delimiter-post-images to correct the spelling.

Filename contains a typo: "iamges" should be "images"

projects/plugins/jetpack/class.jetpack-post-images.php:454

• Add or update unit tests to cover the new Block_Delimiter::scan_delimiters path and the get_images_from_block_attributes() method to ensure coverage of the refactored block parsing logic.

foreach ( Block_Delimiter::scan_delimiters( $html_info['html'] ) as $where => $delimiter ) {

[jp-launch-control]

Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/class.jetpack-post-images.php	319/526 (60.65%)	1.74%	-3 💚

Full summary · PHP report · JS report