fix: reduce relationships to unique values

Author: Mateus Garcia

libs/json-api-nestjs/src/lib/mixin/service/transform/transform.mixin.ts

@@ -186,10 +186,17 @@ export class TransformMixinService<T> {
         const propsData = data[field];
         const typeName = getEntityName(this.relationTarget.get(field));
         if (Array.isArray(propsData)) {
-          builtData.data = propsData.map((i) => ({
-            type: camelToKebab(typeName),
-            id: i[this.relationPrimaryField.get(field)].toString(),
-          }));
+          builtData.data = propsData
+            .map((i) => ({
+              type: camelToKebab(typeName),
+              id: i[this.relationPrimaryField.get(field)].toString(),
+            }))
+            .reduce((acum, i) => {
+              if (acum.find((a) => a.id === i.id)) {
+                return acum;
+              }
+              return [...acum, i];
+            }, []);
         }
 
         if (!Array.isArray(data[field]) && typeof data[field] !== 'undefined') {

libs/json-api-nestjs/src/lib/mixin/service/typeorm/methods/get-one/get-one.spec.ts

@@ -3,7 +3,14 @@ import { getDataSourceToken, getRepositoryToken } from '@nestjs/typeorm';
 import { BadRequestException, NotFoundException } from '@nestjs/common';
 
 import { TypeormMixinService } from '../../typeorm.mixin';
-import { mockDBTestModule, Users, Addresses } from '../../../../../mock-utils';
+import {
+  mockDBTestModule,
+  Users,
+  Addresses,
+  Notes,
+  Comments,
+  Roles,
+} from '../../../../../mock-utils';
 import { ConfigParam, QueryField, QueryParams } from '../../../../../types';
 import { DataSource, Repository } from 'typeorm';
 import {
@@ -84,11 +91,42 @@ describe('GetOne methode test', () => {
       })
     );
 
+    await repository.manager.getRepository(Roles).save(
+      Object.assign(new Roles(), {
+        name: 'user',
+        key: 'USER',
+        isDefault: true,
+      })
+    );
+
+    const comments = await repository.manager.getRepository(Comments).save([
+      Object.assign(new Comments(), {
+        kind: 'COMMENT',
+        text: 'text',
+      }),
+      Object.assign(new Comments(), {
+        kind: 'COMMENT',
+        text: 'text',
+      }),
+      Object.assign(new Comments(), {
+        kind: 'COMMENT',
+        text: 'text',
+      }),
+    ]);
+
+    const notes = await repository.manager.getRepository(Notes).save([
+      Object.assign(new Notes(), {
+        text: 'text',
+      }),
+    ]);
+
     const user = {
       login: 'login',
       lastName: 'lastName',
       isActive: true,
       addresses: addresses,
+      comments,
+      notes,
     };
     await repository.save(Object.assign(new Users(), user));
   });
@@ -188,6 +226,17 @@ describe('GetOne methode test', () => {
     expect(selectSpy).toBeCalledWith([...defaultField['include'], aliasString]);
   });
 
+  it('included relationships should only return unique values', async () => {
+    defaultField['include'] = ['comments', 'notes'];
+    const res = await typeormService.getOne({
+      query: defaultField,
+      route: { id: params },
+    });
+
+    expect(res.data['relationships'].comments.data.length).toBe(3);
+    expect(res.data['relationships'].notes.data.length).toBe(1);
+  });
+
   it('Should be correct query with params', async () => {
     let joinSpy;
     let selectSpy;