feat: support dot notation syntax for nested relations (#739)

src/paginate.spec.ts

@@ -710,7 +710,7 @@ describe('paginate', () => {
         expect(result.links.current).toBe('?page=1&limit=20&sortBy=id:ASC&search=Garfield')
     })
 
-    it('should load nested relations', async () => {
+    it('should load nested relations (object notation)', async () => {
         const config: PaginateConfig<CatEntity> = {
             relations: { home: { pillows: true } },
             sortableColumns: ['id', 'name'],
@@ -743,6 +743,39 @@ describe('paginate', () => {
         expect(result.data[0].home.pillows).toStrictEqual(cat.home.pillows)
     })
 
+    it('should load nested relations (array notation)', async () => {
+        const config: PaginateConfig<CatEntity> = {
+            relations: ['home.pillows'],
+            sortableColumns: ['id', 'name'],
+            searchableColumns: ['name'],
+        }
+        const query: PaginateQuery = {
+            path: '',
+            search: 'Garfield',
+        }
+
+        const result = await paginate<CatEntity>(query, catRepo, config)
+
+        const cat = clone(cats[1])
+        const catHomesClone = clone(catHomes[1])
+        const catHomePillowsClone3 = clone(catHomePillows[3])
+        delete catHomePillowsClone3.home
+        const catHomePillowsClone4 = clone(catHomePillows[4])
+        delete catHomePillowsClone4.home
+        const catHomePillowsClone5 = clone(catHomePillows[5])
+        delete catHomePillowsClone5.home
+
+        catHomesClone.countCat = cats.filter((cat) => cat.id === catHomesClone.cat.id).length
+        catHomesClone.pillows = [catHomePillowsClone3, catHomePillowsClone4, catHomePillowsClone5]
+        cat.home = catHomesClone
+        delete cat.home.cat
+
+        expect(result.meta.search).toStrictEqual('Garfield')
+        expect(result.data).toStrictEqual([cat])
+        expect(result.data[0].home).toBeDefined()
+        expect(result.data[0].home.pillows).toStrictEqual(cat.home.pillows)
+    })
+
     it('should throw an error when nonexistent relation loaded', async () => {
         const config: PaginateConfig<CatEntity> = {
             relations: <any>['homee'],

src/paginate.ts

@@ -6,6 +6,7 @@ import {
     FindOptionsRelations,
     ObjectLiteral,
     FindOptionsUtils,
+    FindOptionsRelationByString,
 } from 'typeorm'
 import { PaginateQuery } from './decorator'
 import { ServiceUnavailableException, Logger } from '@nestjs/common'
@@ -28,6 +29,7 @@ import {
     getQueryUrlComponents,
 } from './helper'
 import { addFilter, FilterOperator, FilterSuffix } from './filter'
+import { OrmUtils } from 'typeorm/util/OrmUtils'
 
 const logger: Logger = new Logger('nestjs-paginate')
 
@@ -61,7 +63,7 @@ export enum PaginationType {
 }
 
 export interface PaginateConfig<T> {
-    relations?: FindOptionsRelations<T> | RelationColumn<T>[]
+    relations?: FindOptionsRelations<T> | RelationColumn<T>[] | FindOptionsRelationByString
     sortableColumns: Column<T>[]
     nullSort?: 'first' | 'last'
     searchableColumns?: Column<T>[]
@@ -123,16 +125,9 @@ export async function paginate<T extends ObjectLiteral>(
     }
 
     if (config.relations) {
-        // relations: ["relation"]
-        if (Array.isArray(config.relations)) {
-            config.relations.forEach((relation) => {
-                queryBuilder.leftJoinAndSelect(
-                    `${queryBuilder.alias}.${relation}`,
-                    `${queryBuilder.alias}_${relation}_rel`
-                )
-            })
-        } else {
-            // relations: {relation:true}
+        const relations = Array.isArray(config.relations)
+            ? OrmUtils.propertyPathsToTruthyObject(config.relations)
+            : config.relations
         const createQueryBuilderRelations = (
             prefix: string,
             relations: FindOptionsRelations<T> | RelationColumn<T>[],
@@ -148,16 +143,11 @@ export async function paginate<T extends ObjectLiteral>(
                 )
 
                 if (typeof relationSchema === 'object') {
-                        createQueryBuilderRelations(
-                            relationName,
-                            relationSchema,
-                            `${alias ?? prefix}_${relationName}_rel`
-                        )
+                    createQueryBuilderRelations(relationName, relationSchema, `${alias ?? prefix}_${relationName}_rel`)
                 }
             })
         }
-            createQueryBuilderRelations(queryBuilder.alias, config.relations)
-        }
+        createQueryBuilderRelations(queryBuilder.alias, relations)
     }
 
     let nullSort: 'NULLS LAST' | 'NULLS FIRST' | undefined = undefined