Background image: add support for relative theme path URLs in top-level theme.json styles

[ramonjd]

What

This PR syncs the PHP changes from:

• Background image: add support for relative theme path URLs in top-level theme.json styles gutenberg#61271

Testing

Important

Until the latest Gutenberg packages are synced, the editor won't parse the relative paths correctly.

I'm using twentytwentyfour to test.

In the theme.json for that theme, add the following to the "styles" object:

		"background": {
			"backgroundImage": {
				"url": "file:./assets/images/windows.webp"
			},
			"backgroundSize": "contain"
		},

Next, add a background image to a style variations, for example src/wp-content/themes/twentytwentyfour/styles/ember.json

		"background": {
			"backgroundImage": {
				"url": "file:./assets/images/abstract-geometric-art.webp"
			},
			"backgroundSize": "cover"
		},

Check the frontend to ensure the correct image is displayed in the background:

Now head over to the site editor and enable the ember variation under Styles > Browse styles. Save and check the frontend.

Ensure the correct image displays (the one from the variation ember.json above).

You can check that _links is added correctly to the REST response through the core data selectors in the browser's console.

To do that, head back to the site editor and open the browser console.

// Get user global styles
await wp.data.resolveSelect( 'core' ).getEntityRecord( 'root', 'globalStyles', await wp.data.resolveSelect( 'core' ).__experimentalGetCurrentGlobalStylesId() )

Check that user styles has a _links entry with theme-uris. It should if you saved the switch to the ember variation.

// Get global styles items (variations)
await wp.data.resolveSelect( 'core' ).__experimentalGetCurrentThemeGlobalStylesVariations()

Check that the Ember item has a _links entry with theme-uris.

// Get all revisions.
await wp.data.resolveSelect( 'core' ).getRevisions( 'root', 'globalStyles', await wp.data.resolveSelect( 'core' ).__experimentalGetCurrentGlobalStylesId() ) 

Check that the latest revision (the one where you saved the Ember variation) item has a _links entry with theme-uris.

Trac ticket: https://core.trac.wordpress.org/ticket/61273

---

This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

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[noisysocks]

I created a local branch containing this PR and #6482 and, with the Gutenberg plugin disabled, I tested creating a new block theme that uses a local file:./ image. The relative URL was not being turned into an absolute URL in the site frontend.

I think you're missing this change:

https://github.com/WordPress/gutenberg/pull/61271/files#diff-b49a48d455acd888a968ee6facf9fb00d9c3de6f91d2818bbe9ddaa4b812dd55

[ramonjd]

I created a local branch containing this PR and #6482 and, with the Gutenberg plugin disabled, I tested creating a new block theme that uses a local file:./ image. The relative URL was not being turned into an absolute URL in the site frontend.

Ah, nice spotting. Thanks! 🙇🏻

I'll update and push quickly.

TBH I'd stopped working on this in anticipation of #6482 getting in first.

[noisysocks]

You asked me to test these two PRs so, ready or not, I'm testing these two PRs 😛

[ramonjd]

You asked me to test these two PRs so, ready or not, I'm testing these two PRs

🍺 You got me. 😄

[github-actions]

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Props ramonopoly, noisysocks.

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[noisysocks]

Code looks correctly ported to me—just a few small things to fix.

I tested this by creating a new empty theme and using a relative URL in background.backgroundImage.url and all was well.

[noisysocks]

Looking good. Would you mind adding step-by-step instructions for how to test the changes to class-wp-rest-global-styles-controller.php and class-wp-rest-global-styles-revisions-controller.php? I couldn't quite figure it out from hitting API endpoints locally.

[noisysocks]

Thanks! LGTM 👍

[noisysocks]

Committed in r58262.

[mukeshpanchal27]

Remove space before variable

[mukeshpanchal27]

Remove space.