From 97106c28e8549b29f438c1c1aa1e37478b3bf450 Mon Sep 17 00:00:00 2001
From: ChengLei Shao <chareice@live.com>
Date: Mon, 12 Jun 2023 18:44:43 +0800
Subject: [PATCH] chore(database): return emtpy fields when attributes not
 specified (#2034)

* test: append nested field

* chore: return emtpy fields when attributes not specified

* fix: test

* fix: data template error

---------

Co-authored-by: chenos <chenlinxh@gmail.com>
---
 .../src/__tests__/field-options/sort-by.test.ts       |  3 ++-
 .../database/src/__tests__/repository/find.test.ts    | 11 +++++++++++
 .../database/src/eager-loading/eager-loading-tree.ts  |  3 ++-
 packages/core/server/src/middlewares/data-template.ts |  2 +-
 4 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/packages/core/database/src/__tests__/field-options/sort-by.test.ts b/packages/core/database/src/__tests__/field-options/sort-by.test.ts
index e9f194606..62ed4a724 100644
--- a/packages/core/database/src/__tests__/field-options/sort-by.test.ts
+++ b/packages/core/database/src/__tests__/field-options/sort-by.test.ts
@@ -151,10 +151,11 @@ describe('associated field order', () => {
     });
 
     const u1 = await db.getRepository('users').findOne({
-      appends: ['posts.tags'],
+      appends: ['posts.tags', 'posts.title'],
     });
 
     const u1Json = u1.toJSON();
+
     const u1Posts = u1Json['posts'];
     expect(u1Posts.map((p) => p['title'])).toEqual(['a', 'b', 'c']);
 
diff --git a/packages/core/database/src/__tests__/repository/find.test.ts b/packages/core/database/src/__tests__/repository/find.test.ts
index 7f5520f94..e3732fe02 100644
--- a/packages/core/database/src/__tests__/repository/find.test.ts
+++ b/packages/core/database/src/__tests__/repository/find.test.ts
@@ -488,6 +488,17 @@ describe('repository find', () => {
       expect(user['posts']).toBeDefined();
     });
 
+    test('find with nested fields', async () => {
+      const user = await User.repository.findOne({
+        fields: ['posts.comments.content'],
+      });
+
+      const userData = user.toJSON();
+
+      const post = userData['posts'][0];
+      expect(Object.keys(post)).toEqual(['comments']);
+    });
+
     describe('find with appends', () => {
       test('toJSON', async () => {
         const user = await User.repository.findOne({
diff --git a/packages/core/database/src/eager-loading/eager-loading-tree.ts b/packages/core/database/src/eager-loading/eager-loading-tree.ts
index 72d0e7aeb..4d7203fb9 100644
--- a/packages/core/database/src/eager-loading/eager-loading-tree.ts
+++ b/packages/core/database/src/eager-loading/eager-loading-tree.ts
@@ -343,7 +343,8 @@ export class EagerLoadingTree {
         });
       }
 
-      const nodeRawAttributes = node.rawAttributes;
+      // if no attributes are specified, return empty fields
+      const nodeRawAttributes = node.rawAttributes || [];
 
       if (!lodash.isArray(nodeRawAttributes)) {
         return;
diff --git a/packages/core/server/src/middlewares/data-template.ts b/packages/core/server/src/middlewares/data-template.ts
index 02909bf7f..a2a625f4c 100644
--- a/packages/core/server/src/middlewares/data-template.ts
+++ b/packages/core/server/src/middlewares/data-template.ts
@@ -37,7 +37,7 @@ const traverseBelongsToMany = (arr: any[], { collection, exclude = [], through }
   const throughCollection = collection.db.getCollection(through);
   return arr.map((item) => {
     const data = traverseJSON(item[through], { collection: throughCollection, exclude });
-    if (Object.keys(data).length) {
+    if (data && Object.keys(data).length) {
       item[through] = data;
     } else {
       delete item[through];