I made that aggregate query below to handle a social network main feed that will be able to show the posts and then answer then. Is there a way to simplify that query or the right choice for that case is to lookup, unwind and project?
`[
{
$match: {
_id: mongoose.Types.ObjectId(myId),
},
},
{
$addFields: {
following: {
$concatArrays: ["$following", [mongoose.Types.ObjectId(myId)]],
},
},
},
{
$lookup: {
from: "users",
localField: "following",
foreignField: "_id",
as: "following",
},
},
{
$unwind: {
path: "$following",
preserveNullAndEmptyArrays: true,
},
},
{
$project: {
_id: "$following._id",
name: "$following.name",
surname: "$following.surname",
profilePicPath: "$following.profilePicPath",
},
},
{
$lookup: {
from: "posts",
localField: "_id",
foreignField: "parentId",
as: "posts",
},
},
{
$unwind: {
path: "$posts",
preserveNullAndEmptyArrays: true,
},
},
{
$project: {
name: true,
surname: true,
profilePicPath: true,
_id: "$posts._id",
parentId: "$posts.parentId",
content: "$posts.content",
date: "$posts.date",
},
},
{
$lookup: {
from: "answerposts",
localField: "_id",
foreignField: "parentId",
as: "answerPosts",
},
},
{
$unwind: {
path: "$answerPosts",
preserveNullAndEmptyArrays: true,
},
},
{
$project: {
name: true,
surname: true,
profilePicPath: true,
_id: true,
parentId: true,
content: true,
date: true,
answerPosts_id: "$answerPosts._id",
answerPostsOwnerId: "$answerPosts.ownerId",
answerPostsContent: "$answerPosts.content",
answerPostsDate: "$answerPosts.date",
},
},
{
$lookup: {
from: "users",
localField: "answerPostsOwnerId",
foreignField: "_id",
as: "answerPostsOwner",
},
},
{
$unwind: {
path: "$answerPostsOwner",
preserveNullAndEmptyArrays: true,
},
},
{
$project: {
name: true,
surname: true,
profilePicPath: true,
_id: true,
parentId: true,
content: true,
date: true,
answerPosts_id: true,
answerPostsContent: true,
answerPostsDate: true,
answerPostsOwner_name: "$answerPostsOwner.name",
answerPostsOwner_surname: "$answerPostsOwner.surname",
answerPostsOwner_profilePicPath: "$answerPostsOwner.profilePicPath",
},
},
{
$group: {
_id: "$_id",
parentId: {
$first: "$parentId",
},
name: {
$first: "$name",
},
surname: {
$first: "$surname",
},
profilePicPath: {
$first: "$profilePicPath",
},
content: {
$first: "$content",
},
date: {
$first: "$date",
},
answerPosts: {
$push: {
_id: "$answerPosts_id",
name: "$answerPostsOwner_name",
surname: "$answerPostsOwner_surname",
content: "$answerPostsContent",
profilePicPath: "$answerPostsOwner_profilePicPath",
date: "$answerPostsDate",
},
},
},
},
{
$addFields: {
answerPosts: {
$cond: [
{
$in: [{}, "$answerPosts"],
},
[],
"$answerPosts",
],
},
},
},
{
$match: {
_id: {
$ne: null,
},
},
},
{
$sort: {
date: -1,
"answerPosts.date": 1,
},
},
]`
It works that way but I want to know if there is a simpler way to make this query.
