Breadcrumbs use a static pattern but should be updated to a service to get the functions out of the global scope.
Breadcrumbs are a sticking point in the panel-ish controller conversion.
Create a service to manage breadcrumbs
Create the class and register the service
Investigate more about how the system will actually be used.
- on the theme / display level
- modules that provide breadcrumb builder plugins. for this we should investigate the various drupal_set_breadcrumb() that already exist in core.
User interface changes
Breadcrumbs becomes a block
API changes: Introduce BreadcrumbBuilder
drupal_set_breadcrumb() will be deprecated or removed.
Instead, we will have a "breadcrumb" service, which can build a breadcrumb for any given request.
The service operates with a series of breadcrumb builder objects, representing the different modules or components of the site that provide breadcrumbs for specific pages - e.g. menu, taxonomy, etc.
The main breadcrumb service will iterate over the registered builder objects, until one of them provides a breadcrumb.
It was discussed whether those builder objects should be services or plugins. For now the consensus is that they should be services, identified by a tag in services.yml.
Drupal 7 contrib has some interesting advanced solutions for breadcrumb building, that outshine what we are doing here.
In this discussion were mentioned:
- Path breadcrumbs, mentioned in
- Crumbs, mentioned in #7 (donquixote), and #36 (bojanz). This shares the basic ideas of this core architecture, but takes it to a new level:
- Not the entire breadcrumb, but each segment, is individually negotiated by plugins.
- Plugins can be sorted in a fine-grained manner.
- The breadcrumb is built leaf-to-root in a hierarchical way, allowing to combine segments/joins provided by different plugins that do not know about each other.
It would have been an option to put some of this into core, but
- this would have been a lot of work, and we don't have enough time before freeze.
- It would prevent contrib to further improve those systems.
Instead, what we focus on here is:
- Architectural clean-up of the D7 core breadcrumb system.
- Keep it simple, leave advanced use cases to contrib.
- Roll out the red carpet for contrib modules: Allow contrib modules to either provide specific breadcrumb builders, or replace the entire breadcrumb service.
Original, but deprecated part of the issue summary
API changes (deprecated)
PASSED: [[SimpleTest]]: [MySQL] 57,719 pass(es). View
FAILED: [[SimpleTest]]: [MySQL] Drupal installation failed. View