Node.js Mongoose聚合未返回最新文档
我有一个返回文档的聚合,但我需要它返回集合messageTrackingId中最新的文档。在Node.js Mongoose聚合未返回最新文档,node.js,mongodb,mongoose,aggregation-framework,Node.js,Mongodb,Mongoose,Aggregation Framework,我有一个返回文档的聚合,但我需要它返回集合messageTrackingId中最新的文档。在creationDate字段中具有最新值的文档我有一个排序来完成这项工作,但我不断收到返回的文档不是最新的,我不知道为什么。目的是向用户显示该用户与另一用户之间发送的最后一条消息的时间戳,而不管是谁发送的。谢谢你的帮助 app.get("/api/messages", (req, res, next) => { query = {}; inbox = false; messageId =
creationDate
字段中具有最新值的文档我有一个排序来完成这项工作,但我不断收到返回的文档不是最新的,我不知道为什么。目的是向用户显示该用户与另一用户之间发送的最后一条消息的时间戳,而不管是谁发送的。谢谢你的帮助
app.get("/api/messages", (req, res, next) => {
query = {};
inbox = false;
messageId = false;
console.log(req.query.recipientId);
if (req.query.recipientId) {
query = { recipientId: req.query.recipientId };
inbox = true;
Messages.aggregate([
{
$match: {
$or: [
{ recipientId: req.query.recipientId },
{ creator: mongoose.Types.ObjectId(req.query.recipientId) }
]
}
},
{
$addFields: {
conversant: {
$cond: [
{ $ne: ["$recipientId", req.query.recipientId] },
"$recipientId",
"$creator"
]
}
}
},
{
$sort: { creationDate: 1 }
},
{
$group: {
_id: "$conversant",
message: { $last: "$message" },
recipientId: { $last: "$recipientId" },
creator: { $last: "$creator" },
messageTrackingId: { $last: "$messageTrackingId" },
recipient: { $last: "$recipient" },
creationDate: { $last: "$creationDate" }
}
},
{
$lookup: {
from: "users",
let: { creator: "$creator" },
pipeline: [
{ $match: { $expr: { $eq: ["$_id", "$$creator"] } } },
{ $project: { instagramName: 1 } }
],
as: "creatorName"
}
}
]).then(documents => {
if (inbox === true) {
res.status(200).json({
message: "User's Inbox Retrieved!",
posts: documents
});
}
});
我清理了消息表,来回发送了3条消息进行演示。当我重新加载页面时,我只收到JSON响应中的2个文档,而不是最新的一个。在收到的2封信中,似乎也没有一封是最新的。我不知道为什么它不返回一个。请参阅下面页面加载上的输出
消息:
/* 1 */
{
"_id" : "5e16463be5fcba1d2c56ebb7",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"recipient" : "andy",
"recipientId" : "5df0014e25ee451beccf588a",
"message" : "First message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:14:35.104Z"),
"__v" : 0.0
}
/* 2 */
{
"_id" : "5e16464de5fcba1d2c56ebb9",
"creator" : "5df0014e25ee451beccf588a",
"recipient" : "buyer1",
"recipientId" : "5e0a1d41f86e1e4234fc1a77",
"message" : "Second Message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "andy",
"creationDate" : ISODate("2020-01-08T21:14:53.618Z"),
"__v" : 0.0
}
/* 3 */
{
"_id" : "5e16465ce5fcba1d2c56ebbb",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"recipient" : "andy",
"recipientId" : "5df0014e25ee451beccf588a",
"message" : "Third Message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:15:08.500Z"),
"__v" : 0.0
}
/* 1 */
{
"_id" : "5df00d08c713f722909c99c1",
"email" : "joe@gmail.com",
"password" : "$2b$10$5eWhwL4RNT8TyQRCC191J.myYBwFcJ8hCARqGfofYWUmRaq6jJFQm",
"instagramName" : "joe",
"over21" : "Yes",
"role" : "Artist",
"fullName" : "testdsfdfsfs",
"address1" : "adfsdf",
"address2" : "dssdf",
"city" : "sdfsdfsdf",
"state" : "dsffsdsd",
"zip" : "dsdfsdf",
"passwordCreated" : ISODate("2020-01-07T23:46:57.861Z"),
"__v" : 0
}
/* 2 */
{
"_id" : "5df0014e25ee451beccf588a",
"email" : "andy@gmail.com",
"password" : "$2b$10$fNHmIoDb4mX6x.YeMLXHbu2yIaeW6HVQvNpZR8Nt/a4xVFkhxM1Ey",
"instagramName" : "andy",
"over21" : "Yes",
"role" : "Artist",
"fullName" : "dsfdsfdfdsf",
"address1" : "111",
"address2" : "111",
"city" : "atlanta",
"state" : "ga",
"zip" : "33222",
"passwordCreated" : ISODate("2019-12-19T15:29:46.528Z"),
"__v" : 0
}
/* 1 */
{
"_id" : {
"conversant" : "5df0014e25ee451beccf588a",
"recipient" : "andy"
},
"message" : "Third Message",
"recipientId" : "5df0014e25ee451beccf588a",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"recipient" : "andy",
"creationDate" : ISODate("2020-01-08T21:15:08.500Z"),
"creatorName" : [
{
"_id" : "5df0014e25ee451beccf588a",
"instagramName" : "andy"
}
]
}
/* 2 */
{
"_id" : {
"conversant" : "5df0014e25ee451beccf588a",
"recipient" : "buyer1"
},
"message" : "Second Message",
"recipientId" : "5e0a1d41f86e1e4234fc1a77",
"creator" : "5df0014e25ee451beccf588a",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"recipient" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:14:53.618Z"),
"creatorName" : [
{
"_id" : "5df0014e25ee451beccf588a",
"instagramName" : "andy"
}
]
}
用户:
/* 1 */
{
"_id" : "5e16463be5fcba1d2c56ebb7",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"recipient" : "andy",
"recipientId" : "5df0014e25ee451beccf588a",
"message" : "First message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:14:35.104Z"),
"__v" : 0.0
}
/* 2 */
{
"_id" : "5e16464de5fcba1d2c56ebb9",
"creator" : "5df0014e25ee451beccf588a",
"recipient" : "buyer1",
"recipientId" : "5e0a1d41f86e1e4234fc1a77",
"message" : "Second Message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "andy",
"creationDate" : ISODate("2020-01-08T21:14:53.618Z"),
"__v" : 0.0
}
/* 3 */
{
"_id" : "5e16465ce5fcba1d2c56ebbb",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"recipient" : "andy",
"recipientId" : "5df0014e25ee451beccf588a",
"message" : "Third Message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:15:08.500Z"),
"__v" : 0.0
}
/* 1 */
{
"_id" : "5df00d08c713f722909c99c1",
"email" : "joe@gmail.com",
"password" : "$2b$10$5eWhwL4RNT8TyQRCC191J.myYBwFcJ8hCARqGfofYWUmRaq6jJFQm",
"instagramName" : "joe",
"over21" : "Yes",
"role" : "Artist",
"fullName" : "testdsfdfsfs",
"address1" : "adfsdf",
"address2" : "dssdf",
"city" : "sdfsdfsdf",
"state" : "dsffsdsd",
"zip" : "dsdfsdf",
"passwordCreated" : ISODate("2020-01-07T23:46:57.861Z"),
"__v" : 0
}
/* 2 */
{
"_id" : "5df0014e25ee451beccf588a",
"email" : "andy@gmail.com",
"password" : "$2b$10$fNHmIoDb4mX6x.YeMLXHbu2yIaeW6HVQvNpZR8Nt/a4xVFkhxM1Ey",
"instagramName" : "andy",
"over21" : "Yes",
"role" : "Artist",
"fullName" : "dsfdsfdfdsf",
"address1" : "111",
"address2" : "111",
"city" : "atlanta",
"state" : "ga",
"zip" : "33222",
"passwordCreated" : ISODate("2019-12-19T15:29:46.528Z"),
"__v" : 0
}
/* 1 */
{
"_id" : {
"conversant" : "5df0014e25ee451beccf588a",
"recipient" : "andy"
},
"message" : "Third Message",
"recipientId" : "5df0014e25ee451beccf588a",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"recipient" : "andy",
"creationDate" : ISODate("2020-01-08T21:15:08.500Z"),
"creatorName" : [
{
"_id" : "5df0014e25ee451beccf588a",
"instagramName" : "andy"
}
]
}
/* 2 */
{
"_id" : {
"conversant" : "5df0014e25ee451beccf588a",
"recipient" : "buyer1"
},
"message" : "Second Message",
"recipientId" : "5e0a1d41f86e1e4234fc1a77",
"creator" : "5df0014e25ee451beccf588a",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"recipient" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:14:53.618Z"),
"creatorName" : [
{
"_id" : "5df0014e25ee451beccf588a",
"instagramName" : "andy"
}
]
}
所需输出(返回每个用户的最后一条消息):
/* 1 */
{
"_id" : "5e16463be5fcba1d2c56ebb7",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"recipient" : "andy",
"recipientId" : "5df0014e25ee451beccf588a",
"message" : "First message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:14:35.104Z"),
"__v" : 0.0
}
/* 2 */
{
"_id" : "5e16464de5fcba1d2c56ebb9",
"creator" : "5df0014e25ee451beccf588a",
"recipient" : "buyer1",
"recipientId" : "5e0a1d41f86e1e4234fc1a77",
"message" : "Second Message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "andy",
"creationDate" : ISODate("2020-01-08T21:14:53.618Z"),
"__v" : 0.0
}
/* 3 */
{
"_id" : "5e16465ce5fcba1d2c56ebbb",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"recipient" : "andy",
"recipientId" : "5df0014e25ee451beccf588a",
"message" : "Third Message",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"creatorName" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:15:08.500Z"),
"__v" : 0.0
}
/* 1 */
{
"_id" : "5df00d08c713f722909c99c1",
"email" : "joe@gmail.com",
"password" : "$2b$10$5eWhwL4RNT8TyQRCC191J.myYBwFcJ8hCARqGfofYWUmRaq6jJFQm",
"instagramName" : "joe",
"over21" : "Yes",
"role" : "Artist",
"fullName" : "testdsfdfsfs",
"address1" : "adfsdf",
"address2" : "dssdf",
"city" : "sdfsdfsdf",
"state" : "dsffsdsd",
"zip" : "dsdfsdf",
"passwordCreated" : ISODate("2020-01-07T23:46:57.861Z"),
"__v" : 0
}
/* 2 */
{
"_id" : "5df0014e25ee451beccf588a",
"email" : "andy@gmail.com",
"password" : "$2b$10$fNHmIoDb4mX6x.YeMLXHbu2yIaeW6HVQvNpZR8Nt/a4xVFkhxM1Ey",
"instagramName" : "andy",
"over21" : "Yes",
"role" : "Artist",
"fullName" : "dsfdsfdfdsf",
"address1" : "111",
"address2" : "111",
"city" : "atlanta",
"state" : "ga",
"zip" : "33222",
"passwordCreated" : ISODate("2019-12-19T15:29:46.528Z"),
"__v" : 0
}
/* 1 */
{
"_id" : {
"conversant" : "5df0014e25ee451beccf588a",
"recipient" : "andy"
},
"message" : "Third Message",
"recipientId" : "5df0014e25ee451beccf588a",
"creator" : "5e0a1d41f86e1e4234fc1a77",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"recipient" : "andy",
"creationDate" : ISODate("2020-01-08T21:15:08.500Z"),
"creatorName" : [
{
"_id" : "5df0014e25ee451beccf588a",
"instagramName" : "andy"
}
]
}
/* 2 */
{
"_id" : {
"conversant" : "5df0014e25ee451beccf588a",
"recipient" : "buyer1"
},
"message" : "Second Message",
"recipientId" : "5e0a1d41f86e1e4234fc1a77",
"creator" : "5df0014e25ee451beccf588a",
"messageTrackingId" : "17c4fc99-d92f-46ef-9bae-1408f415287a",
"recipient" : "buyer1",
"creationDate" : ISODate("2020-01-08T21:14:53.618Z"),
"creatorName" : [
{
"_id" : "5df0014e25ee451beccf588a",
"instagramName" : "andy"
}
]
}
必须改变
1) 如果我在此阶段理解正确,您希望在一个字段上按recipientId
分组(因为您不能为一个值在两个字段上分组),因此您正在创建一个名为conversant
的新字段,因此,它必须是$eq
,或者您需要交换接收方ID
和创建者
&它也必须是$toString
:
{
$addFields: {
conversant: {
$cond: [
{ $eq: ["$recipientId", req.query.recipientId] },
"$recipientId",
{$toString : "$creator"}
]
}
}
}
2) 您不需要此$sort
阶段,因为所有最新添加到集合中的内容都将在末尾添加(预期creationDate
一次创建,但从未更新):
此外,您还需要根据\u id:{conversant:$conversant],recipient:'$recipient'}
对基于用户的最后一封邮件进行分组。在$lookup
中更改为该让:{conversant:$\u id.conversant“}
试试这个:
Messages.aggregate([
{
$match: {
$or: [
{ recipientId: req.query.recipientId },
{ creator: mongoose.Types.ObjectId(req.query.recipientId) }
]
}
},
{
$addFields: {
conversant: {
$cond: [
{ $eq: ["$recipientId", req.query.recipientId] },
"$recipientId",
{ $toString: "$creator" }
]
}
}
},
{
$group: {
_id: { conversant: "$conversant", recipient: '$recipient' },
message: { $last: "$message" },
recipientId: { $last: "$recipientId" },
creator: { $last: "$creator" },
messageTrackingId: { $last: "$messageTrackingId" },
recipient: { $last: "$recipient" },
creationDate: { $last: "$creationDate" }
}
},
{
$lookup: {
from: "users",
let: { conversant: "$_id.conversant" },
pipeline: [
{ $match: { $expr: { $eq: ["$_id", "$$conversant"] } } },
{ $project: { instagramName: 1 } }
],
as: "creatorName"
}
},
// this is optional only if you wanted to return latest document irrespective of user.
{ $sort: { creationDate: -1 } }
])
我相信如果你能提供样本文档和你得到的结果,以便更好地理解正在发生的事情,这是可以理解的,但是如果你能提供上述样本文档,那就更好了。我对{conversant:{$cond:[{$ne:[“$recipientId”,req.query.recipientId]},“$recipientId”,“$creator”]}
进行了一些编辑,如果我理解正确,那么在这个阶段,您希望通过字段上的recipientId
进行分组(因为不能为单个值在两个字段上分组)所以您正在创建一个新字段,是不是$ne
?我想应该是$eq
!!我将conversant更新为$eq
,而不是nq
,当我刷新页面时,从JSON响应返回的2个文档中没有一个是最新的文档。我添加了-1
,但问题仍然存在。下面是一个更新参考代码的ed版本:从我的测试来看,当用户发送消息时,他们现在似乎拥有最新的文档,这很好,但收件人似乎对最新的文档有点不满意。我一直在来回登录和注销每个用户帐户,最终它不会用它来提取最新的文档messageTracking Id。此表应具有最新日期,但应显示3:08:13而不是3:07:49