I've got User and Post models. User.favPosts is an array of refs to the Post model. I'm calling paginate like this:
options = { populate: {path: 'favPosts'} };
const result = await User.paginate({}, options)
And the result is a user document with populated posts:
{
"docs": [
{
"_id": "6299ffa5c2ca4cdeebd1f513",
"name": "user",
"email": "email@mail.com",
"favPosts": [
{
"_id": "629b299897f46f31761ad7a7",
"title": "Available Test 5",
"description": "Lorem ipsum dolor sit"
},
{
"_id": "629b1edf108e765744d2560d",
"title": "Available Test 4",
"description": "Lorem ipsum dolor sit"
},
{
"_id": "629b1c0027bf0eb197c057dd",
"title": "Available Test 4",
"description": "Lorem ipsum dolor sit"
}
]
}
],
"totalDocs": 1,
"offset": 0,
"limit": 10,
"totalPages": 1,
"page": 1,
"pagingCounter": 1,
"hasPrevPage": false,
"hasNextPage": false,
"prevPage": null,
"nextPage": null
}
So I'm getting the pagination of users. But I want to get pagination of populated documents (posts), so I could get the amount of these, page counting, etc. So I want the result to look like this:
{
"docs": [
{
"_id": "629b299897f46f31761ad7a7",
"title": "Available Test 5",
"description": "Lorem ipsum dolor sit"
},
{
"_id": "629b1edf108e765744d2560d",
"title": "Available Test 4",
"description": "Lorem ipsum dolor sit"
},
{
"_id": "629b1c0027bf0eb197c057dd",
"title": "Available Test 4",
"description": "Lorem ipsum dolor sit"
}
],
"totalDocs": 3,
"offset": 0,
"limit": 10,
"totalPages": 1,
"page": 1,
"pagingCounter": 1,
"hasPrevPage": false,
"hasNextPage": false,
"prevPage": null,
"nextPage": null
}
Can somebody tell me, is it possible to do such a thing via the mongoose-paginate-v2?
Here's how I solved it. I used the mongoose-aggregate-paginate-v2 module instead of mongoose-paginate-v2:
const aggregate = User.aggregate([ // without "await", so it will be a Promise
{ $match: { userId } }, // filter for users collection
{
// populating posts:
$lookup: {
from: 'posts',
localField: 'favPosts',
foreignField: '_id',
as: 'documents',
pipeline, // here's filter for posts
},
},
// unwind + replaceRoot to get an array of posts to the root, so this would be the posts array instead of the users array
{
$unwind: '$documents',
},
{
$replaceRoot: { newRoot: '$documents' },
},
]);
And then feeding this Promise to the paginator:
const options = { page: 2, limit: 10 };
const result = await User.aggregatePaginate(aggregate, options);