Introduce an XB `PageTemplate` config entity

I have a question that I’ve been thinking about around this, maybe a bit early to answer

Let’s say I have a header region, and I place a Hero component in that region. The Hero component an background image (Media entity)

How will that work? Let’s say I build the page template locally and then push the config entity to production, there is no guarantee that the media with that ID exists so the default will be broken image when you create a page.

Thinking loudly… Should page templates e.g be allowed to save “incomplete” components, or do we need some placeholder feature generic, or specifically for media?

wim leers → credited effulgentsia → .

wim leers → credited lauriii → .

This is progressing nicely. An incomplete PageTemplate config entity now fails as expected:

1) Drupal\Tests\experience_builder\Kernel\Config\PageTemplateValidationTest::testEntityIsValid
Failed asserting that two arrays are identical.
--- Expected
+++ Actual
@@ @@
-Array &0 []
+Array &0 [
+    'component_trees' => Array &1 [
+        0 => 'Configuration for the region "<em class="placeholder">sidebar_first</em>" (<em class="placeholder">sidebar_first</em>) is missing.',
+        1 => 'Configuration for the region "<em class="placeholder">sidebar_second</em>" (<em class="placeholder">sidebar_second</em>) is missing.',
+        2 => 'Configuration for the region "<em class="placeholder">content</em>" (<em class="placeholder">content</em>) is missing.',
+        3 => 'Configuration for the region "<em class="placeholder">header</em>" (<em class="placeholder">header</em>) is missing.',
+        4 => 'Configuration for the region "<em class="placeholder">primary_menu</em>" (<em class="placeholder">primary_menu</em>) is missing.',
+        5 => 'Configuration for the region "<em class="placeholder">secondary_menu</em>" (<em class="placeholder">secondary_menu</em>) is missing.',
+        6 => 'Configuration for the region "<em class="placeholder">footer</em>" (<em class="placeholder">footer</em>) is missing.',
+        7 => 'Configuration for the region "<em class="placeholder">highlighted</em>" (<em class="placeholder">highlighted</em>) is missing.',
+        8 => 'Configuration for the region "<em class="placeholder">help</em>" (<em class="placeholder">help</em>) is missing.',
+        9 => 'Configuration for the region "<em class="placeholder">page_top</em>" (<em class="placeholder">page_top</em>) is missing.',
+        10 => 'Configuration for the region "<em class="placeholder">page_bottom</em>" (<em class="placeholder">page_bottom</em>) is missing.',
+        11 => 'Configuration for the region "<em class="placeholder">breadcrumb</em>" (<em class="placeholder">breadcrumb</em>) is missing.',
+    ],
+]

(Also crediting Lauri & Alex.)

How will that work? Let’s say I build the page template locally and then push the config entity to production, there is no guarantee that the media with that ID exists so the default will be broken image when you create a page.

The way this works with similar things now is you would have to do this:

1. Create the media entity on production
2. Sync the production database locally
3. Set up the layout (or whatever config entity referencing the content entity).
4. Deploy the config and everything works

This works but is of course very clunky. Feels like a separate issue since it's more of a general problem with config entities that reference config entities rather than XB specific, although agreed it's going to be a common thing people want to do.

#3: @catch is right in #7 and is also right that this is out of scope here, but merits its own issue. For now, let's discuss this on the meta, because this is a challenge affecting multiple of XB's config entity types. See prior discussion at #3444424-4: [META] Configuration management: define needed config entity types → from >4 months ago, where I link to a PoC that we built >5 months ago that shows a viable way to fix that.

Let's not discuss that further here 🙏

Will continue on Monday, but this is ready for an initial high-level review. 👍

Continuing…

A few questions but mostly nits, I think the overall approach is sound.

@lauriii A review from @longwave surfaced two important questions, and I answered both by adding explicit "warning, future stuff" docs for both. Can you confirm the accuracy of these 2 small paragraphs? 🙏

#15: That looks good 👍 Those are limitations I'm aware of for the current state of XB.

Thanks @lauriii! Incorporated your suggested refinement too 👍

All feedback from @longwave has now been addressed, back to him for review.

I did a (fairly quick/cursory) review of this and couldn't see any obvious problems, just one question in the MR.

Good question/suggestion, @catch! Responded :)

The HTTP API follow-up exists: 📌 HTTP API to read+write PageTemplate and Pattern config entities Active .

Merged in upstream and did a trivial search-and-replace to compensate for 📌 Replace plus with dot in component config entity IDs Active having landed.

FYI: 📌 HTTP API to read+write PageTemplate and Pattern config entities Active is making good progress and will allow a (client-side) UI to be built, allowing to reuse significant pieces of the existing UX :)

Follow-up created per @lauriii's feedback: 📌 [later phase] [PP-1] Gracefully handle deleted regions in PageTemplate config entities" Postponed .

Again only another round of tiny nits, I still think this is a solid base for the desired functionality here.

Thanks, this looks great now, and unblocks future work. Let's ship it!

Automatically closed - issue fixed for 2 weeks with no activity.