Add test + update logic

packages/core/database/lib/query/helpers/populate/apply.js

@@ -490,7 +490,7 @@ const morphToMany = async (input, ctx) => {
     const qb = db.entityManager.createQueryBuilder(type);
 
     const rows = await qb
-      .init(on && type in on ? on[type] : typePopulate)
+      .init(on?.[type] ?? typePopulate)
       .addSelect(`${qb.alias}.${idColumn.referencedColumn}`)
       .where({ [idColumn.referencedColumn]: ids })
       .execute({ mapResults: false });
@@ -561,7 +561,7 @@ const morphToOne = async (input, ctx) => {
     const qb = db.entityManager.createQueryBuilder(type);
 
     const rows = await qb
-      .init(on && type in on ? on[type] : typePopulate)
+      .init(on?.[type] ?? typePopulate)
       .addSelect(`${qb.alias}.${idColumn.referencedColumn}`)
       .where({ [idColumn.referencedColumn]: ids })
       .execute({ mapResults: false });

packages/core/strapi/tests/api/populate/filtering/index.test.api.js

@@ -315,4 +315,64 @@ describe('Populate filters', () => {
       expect(body.data[0].attributes.third).toBeUndefined();
     });
   });
+
+  describe('Populate a dynamic zone', () => {
+    test('Populate every components in the dynamic zone', async () => {
+      const qs = {
+        populate: {
+          dz: '*',
+        },
+      };
+
+      const { status, body } = await rq.get(`/${schemas.contentTypes.b.pluralName}`, { qs });
+
+      expect(status).toBe(200);
+      expect(body.data).toHaveLength(2);
+      expect(body.data[0].attributes.dz).toHaveLength(3);
+      expect(body.data[1].attributes.dz).toHaveLength(1);
+    });
+
+    test('Populate only one component type using fragment', async () => {
+      const qs = {
+        populate: {
+          dz: {
+            on: {
+              'default.foo': true,
+            },
+          },
+        },
+      };
+
+      const { status, body } = await rq.get(`/${schemas.contentTypes.b.pluralName}`, { qs });
+
+      expect(status).toBe(200);
+      expect(body.data).toHaveLength(2);
+      expect(body.data[0].attributes.dz).toHaveLength(2);
+      expect(body.data[1].attributes.dz).toHaveLength(0);
+    });
+
+    test('Populate the dynamic zone with filters in fragments', async () => {
+      const qs = {
+        populate: {
+          dz: {
+            on: {
+              'default.foo': {
+                filters: { number: { $lt: 2 } },
+              },
+              'default.bar': {
+                filters: { title: { $contains: 'another' } },
+              },
+            },
+          },
+        },
+      };
+
+      const { status, body } = await rq.get(`/${schemas.contentTypes.b.pluralName}`, { qs });
+
+      expect(status).toBe(200);
+      expect(body.data).toHaveLength(2);
+      expect(body.data[0].attributes.dz).toHaveLength(1);
+      expect(body.data[1].attributes.dz).toHaveLength(1);
+    });
+  });
 });

packages/core/utils/lib/convert-query-params.js

@@ -186,7 +186,15 @@ const convertPopulateObject = (populate, schema) => {
       return acc;
     }
 
-    if (typeof subPopulate === 'object' && 'on' in subPopulate) {
+    // Allow adding a 'on' strategy to populate queries for polymorphic relations, media and dynamic zones
+    const isAllowedAttributeForFragmentPopulate =
+      attribute.type === 'dynamiczone' ||
+      attribute.type === 'media' ||
+      (attribute.relation && attribute.relation.startsWith('morphTo'));
+
+    const hasFragmentPopulateDefined = typeof subPopulate === 'object' && 'on' in subPopulate;
+
+    if (isAllowedAttributeForFragmentPopulate && hasFragmentPopulateDefined) {
       return {
         ...acc,
         [key]: {
@@ -201,8 +209,8 @@ const convertPopulateObject = (populate, schema) => {
       };
     }
 
-    // TODO: Deprecated way of handling dynamic zone populate queries. It's kept as is,
-    // as removing it could break existing user queries but should be removed in V5.
+    // TODO: This is a query's populate fallback for DynamicZone and is kept for legacy purpose.
+    //       Removing it could break existing user queries but it should be removed in V5.
     if (attribute.type === 'dynamiczone') {
       const populates = attribute.components
         .map((uid) => strapi.getModel(uid))