>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3558094. --> Reported by: [jdleonard](https://www.drupal.org/user/80902) Related to !8 >>> <h3 id="summary-problem-motivation">Problem/Motivation</h3> <p>Primary Entity Reference currently provides only minimal Views integration. While the field works correctly in<br> entity forms and renderers, Views cannot:</p> <ul> <li>Create relationships to the referenced entities</li> <li>Filter or sort based on the primary reference flag</li> <li>Expose only the primary referenced entity in listings</li> <li>Match the functionality that core Entity Reference provides in Views</li> </ul> <p>This makes it difficult to use the field in practical reporting and listing scenarios, particularly when a consumer<br> needs to join on, or specifically display, the primary referenced entity.</p> <h4 id="summary-steps-reproduce">Steps to reproduce</h4> <ul> <li>Create a content type that uses a Primary Entity Reference field.</li> <li>Attempt to add the field to a View as a relationship or contextual filter.</li> <li>Only minimal field display is available; no relationships or primary-only capabilities exist.</li> </ul> <h3 id="summary-proposed-resolution">Proposed resolution</h3> <p>Implement full Views integration equivalent to core Entity Reference, using modern<br> <strong>service-based Views data providers</strong> and <strong>auto-wired Hook Attributes</strong>.<br> Instead of a <code>primary_entity_reference.views.inc</code> file or procedural <code>hook_views_data()</code>,<br> the module will register and expose its Views data through attribute-driven services.</p> <p>The implementation would include:</p> <ul> <li><strong>Views data service</strong> <ul> <li>Provide a <code>views.views_data</code> service for Primary Entity Reference.</li> <li>Use Hook Attributes (e.g., <code>#[ViewsData]</code>) to auto-register Views data.</li> <li>Expose field, filter, sort, and relationship metadata programmatically.</li> </ul> </li> <li><strong>Field handler plugin</strong> extending core ER field handler: <ul> <li>Option: Display all referenced entities</li> <li>Option: Display only the primary referenced entity</li> </ul> </li> <li><strong>Relationship plugins</strong>: <ul> <li>A standard ER-style relationship matching core behavior.</li> <li>A primary-only relationship applying a <code>primary = 1</code> join condition.</li> </ul> </li> <li><strong>Filter plugin</strong>: <ul> <li>Filtering by referenced entity with optional &ldquo;primary only&rdquo; mode.</li> </ul> </li> <li><strong>Sort plugin</strong>: <ul> <li>Sorting by weight or by the primary flag.</li> </ul> </li> </ul> <p>Using service discovery and Hook Attributes ensures the module follows modern Drupal patterns and avoids the legacy<br> <code>.views.inc</code> approach entirely.</p> <h3 id="summary-remaining-tasks">Remaining tasks</h3> <ul> <li>Implement Views data provider service with Hook Attributes.</li> <li>Add field, filter, sort, and relationship plugins.</li> <li>Add primary-only relationship logic.</li> <li>Add tests covering each Views integration point.</li> <li>Document config options and usage examples.</li> </ul> <h3 id="summary-ui-changes">User interface changes</h3> <ul> <li>In the field handler options, add a setting to display: <ul> <li>All referenced entities</li> <li>Primary reference only</li> </ul> </li> </ul> <h3 id="summary-api-changes">API changes</h3> <ul> <li>New Views plugins (field, filter, sort, relationship) under <code>Plugin\views\*</code>.</li> <li>New <code>views.views_data</code> service using Hook Attributes.</li> </ul> <h3 id="summary-data-model-changes">Data model changes</h3> <p>No data model changes. The existing <code>primary</code> column already supports the necessary behavior.</p>