使用猫鼬填充时返回一个空的帖子数组
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【中文标题】使用猫鼬填充时返回一个空的帖子数组【英文标题】：Returning an empty array of posts when using mongoose populate 【发布时间】：2020-06-21 16:43:12 【问题描述】：我正在尝试获取特定用户的帖子。它返回给我一个空的帖子数组。这是我的代码。我想我已经正确地引用了所有内容，一定有什么错误。
User model
const Schema = mongoose.Schema
const userSchema = new Schema(
username: type: String, required: true ,
email: type: String, reuired: true ,
password: type: String, required: true ,
posts:[ type: Schema.Types.ObjectId, ref: "Post" ]
, timestamps: true )
Post model
const Schema = mongoose.Schema;
const postSchema = new Schema(
title: type: String, required: true ,
content: type: String, required: true ,
user: type: Schema.Types.ObjectId, ref: "User" ,
, timestamps: true
router.get("/posts/:id", usersController.getUserPosts)
getUserPosts: (req, res) =>
User.findById(req.params.id, async (err, user) =>
if (err)
return res.status(500).json( error: "Server error" )
else if (!user)
return res.status(400).json( error: "No user" )
else if (user)
user = await User.populate("user",
path: "posts",
model: "Post"
)
return res.status(200).json( user )
)
编辑
数据库中的用户是：
/users/list
"users": [
"posts": [],
"_id": "5e66496fcaf5d6697ca3fdbc",
"username": "JimmyPage",
"email": "jimmypage@gmail.com",
"password": "$2b$10$mu0IcHADj5YVIT/66EEfPOxL3cvEjqDsnJUcrST8ZcatTOcQ42kn6",
"createdAt": "2020-03-09T13:49:35.834Z",
"updatedAt": "2020-03-09T13:49:35.834Z",
"__v": 0
,
"posts": [],
"_id": "5e66499fcaf5d6697ca3fdbe",
"username": "AxlRose",
"email": "axlrose@gmail.com",
"password": "$2b$10$H3X3efz02RonlvNXaRPr2eEbflSiFK1ITFdbyT2igUGDK9gDpIJqO",
"createdAt": "2020-03-09T13:50:23.702Z",
"updatedAt": "2020-03-09T13:50:23.702Z",
"__v": 0
]
帖子如下所示：
/posts/list
"posts": [
"_id": "5e66498ccaf5d6697ca3fdbd",
"title": "Jimmy Page's post",
"description": "This is Jimmy Page's post",
"user":
"posts": [],
"_id": "5e66496fcaf5d6697ca3fdbc",
"username": "JimmyPage",
"email": "jimmypage@gmail.com",
"password": "$2b$10$mu0IcHADj5YVIT/66EEfPOxL3cvEjqDsnJUcrST8ZcatTOcQ42kn6",
"createdAt": "2020-03-09T13:49:35.834Z",
"updatedAt": "2020-03-09T13:49:35.834Z",
"__v": 0
,
"createdAt": "2020-03-09T13:50:04.840Z",
"updatedAt": "2020-03-09T13:50:04.840Z",
"__v": 0
,
"_id": "5e6649b5caf5d6697ca3fdbf",
"title": "Axl Rose's Post",
"description": "This is Axl Rose's Post",
"user":
"posts": [],
"_id": "5e66499fcaf5d6697ca3fdbe",
"username": "AxlRose",
"email": "axlrose@gmail.com",
"password": "$2b$10$H3X3efz02RonlvNXaRPr2eEbflSiFK1ITFdbyT2igUGDK9gDpIJqO",
"createdAt": "2020-03-09T13:50:23.702Z",
"updatedAt": "2020-03-09T13:50:23.702Z",
"__v": 0
,
"createdAt": "2020-03-09T13:50:45.751Z",
"updatedAt": "2020-03-09T13:50:45.751Z",
"__v": 0
,
"_id": "5e664b7bf120ab6c0d9999c9",
"title": "Jimmy Page's second post",
"description": "This is Jimmy Page's second post\n\n",
"user":
"posts": [],
"_id": "5e66496fcaf5d6697ca3fdbc",
"username": "JimmyPage",
"email": "jimmypage@gmail.com",
"password": "$2b$10$mu0IcHADj5YVIT/66EEfPOxL3cvEjqDsnJUcrST8ZcatTOcQ42kn6",
"createdAt": "2020-03-09T13:49:35.834Z",
"updatedAt": "2020-03-09T13:49:35.834Z",
"__v": 0
,
"createdAt": "2020-03-09T13:58:19.261Z",
"updatedAt": "2020-03-09T13:58:19.261Z",
"__v": 0
]
我在我的问题中添加了上述代码。我一直被困在这种状态，就像我试图在他的个人资料中显示用户的帖子一样，并且还计划显示所有用户帖子的全球供稿。
如果你能帮助我，那就太好了。我会很感激的。谢谢。
列表帖子控制器是这样的：
listposts: (req, res) =>
Post.find(, async (error, posts) =>
if (error)
return res.status(500).json( error: "something went wrong" )
else if (!posts)
return res.status(400).json( msg: "sorry no posts" )
else if (posts)
posts = await Post.populate(posts,
path: 'user',
model: 'User'
);
return res.status(200).json( posts )
)
用户文档：
"_id" : ObjectId("5e66496fcaf5d6697ca3fdbc"),
"posts" : [ ],
"username" : "JimmyPage",
"email" : "jimmypage@gmail.com",
"password" : "$2b$10$mu0IcHADj5YVIT/66EEfPOxL3cvEjqDsnJUcrST8ZcatTOcQ42kn6",
"createdAt" : ISODate("2020-03-09T13:49:35.834Z"),
"updatedAt" : ISODate("2020-03-09T13:49:35.834Z"), "__v" : 0
"_id" : ObjectId("5e66499fcaf5d6697ca3fdbe"),
"posts" : [ ],
"username" : "AxlRose",
"email" : "axlrose@gmail.com",
"password" : "$2b$10$H3X3efz02RonlvNXaRPr2eEbflSiFK1ITFdbyT2igUGDK9gDpIJqO",
"createdAt" : ISODate("2020-03-09T13:50:23.702Z"),
"updatedAt" : ISODate("2020-03-09T13:50:23.702Z"),
"__v" : 0
还有帖子文件：
"_id" : ObjectId("5e66498ccaf5d6697ca3fdbd"),
"title" : "Jimmy Page's post",
"description" : "This is Jimmy Page's post",
"user" : ObjectId("5e66496fcaf5d6697ca3fdbc"),
"createdAt" : ISODate("2020-03-09T13:50:04.840Z"),
"updatedAt" : ISODate("2020-03-09T13:50:04.840Z"),
"__v" : 0
"_id" : ObjectId("5e6649b5caf5d6697ca3fdbf"),
"title" : "Axl Rose's Post",
"description" : "This is Axl Rose's Post",
"user" : ObjectId("5e66499fcaf5d6697ca3fdbe"),
"createdAt" : ISODate("2020-03-09T13:50:45.751Z"),
"updatedAt" : ISODate("2020-03-09T13:50:45.751Z"),
"__v" : 0
"_id" : ObjectId("5e664b7bf120ab6c0d9999c9"),
"title" : "Jimmy Page's second post",
"description" : "This is Jimmy Page's second post\n\n",
"user" : ObjectId("5e66496fcaf5d6697ca3fdbc"),
"createdAt" : ISODate("2020-03-09T13:58:19.261Z"),
"updatedAt" : ISODate("2020-03-09T13:58:19.261Z"),
"__v" : 0
【问题讨论】：
【参考方案1】：您可以使用以下方法获取用户信息和他/她的帖子。
getUserPosts: async (req, res) =>
try
const user = await User.findById(req.params.id).populate("posts");
if (!user)
return res.status(400).json( error: "No user" );
return res.status(200).json( user );
catch (err)
return res.status(500).json( error: "Server error" );
;
【讨论】：
我收到的帖子仍然是空的。我必须在某处添加帖子 ID。我阅读了其他一些答案，但我不知道如何在这里获取帖子 ID。 @ubuntu7788 你如何为帖子收集创建模型？一定是这样的mongoose.model("Posts", postSchema )。这里的帖子必须与这里的帖子匹配 ref: "Posts"
我的猫鼬模型是export const Post = mongoose.model("Post", postSchema, "posts")。我不知道为什么需要第三个参数 "posts"。这是可选的，对吧？
@ubuntu7788 你需要在用户模式中像posts:[ type: Schema.Types.ObjectId, ref: "Post" ] 这样更改你的引用。我们对第三个参数不感兴趣。
@ubuntu7788 不客气，能否将其标记为答案并点赞？以上是关于使用猫鼬填充时返回一个空的帖子数组的主要内容，如果未能解决你的问题，请参考以下文章