Gegevens filteren met behulp van mangoesten

Probeer dit alstublieft:

Zoals ik al heb voorgesteld, kun je dit gebruiken:

Database.find({})
    .populate({ path: 'components', match: { name: /antr/i }, select: 'name -_id' })
    .exec((err, data) => { console.log(err); res.json(data); });

Aangezien je lege array's ziet, komt dit door de filterquery in match die geen geschikte documenten vindt in componentenverzameling w.r.t. ObjectIds in componentenarray van databasedocument, dit is normaal. Misschien kun je die in code uitfilteren, omdat je niet op die manier kijkt. Je kunt $lookup van mongoDB gebruiken van aggregatieraamwerk dat gelijk is aan .populate() van mangoest.

Database.aggregate(
    [{
        $lookup: {
            from: "components",
            "let": { "ids": "$components" },
            pipeline: [
                { $match: { $expr: { $in: ['$_id', '$$ids'] } } }],
            as: "dbComponentsArray"
        }
    }, { $unwind: '$dbComponentsArray' }, { $match: { 'dbComponentsArray.name': /antr/i } },
    { $group: { _id: '$_id', dbComponentsArray: { $push: '$dbComponentsArray' }, data: { $first: '$$ROOT' } } }, { $addFields: { 'data.dbComponentsArray': '$dbComponentsArray' } },
    { $replaceRoot: { 'newRoot': '$data' } }])

Voorbeeldgegevens in collecties:

componenten :

/* 1 */
{
    "_id" : ObjectId("5d481cd098ba991c0857959f"),
    "name" : "antracito",
    "updatedAt" : ISODate("2019-08-05T12:10:56.777Z"),
    "__v" : 0
}

/* 2 */
{
    "_id" : ObjectId("5d481cd098ba991c0857958f"),
    "name" : "anacito",
    "updatedAt" : ISODate("2019-08-05T12:10:56.777Z"),
    "__v" : 0
}

/* 3 */
{
    "_id" : ObjectId("5d481cd098ba991c0857951f"),
    "name" : "antracito",
    "updatedAt" : ISODate("2019-08-05T12:10:56.777Z"),
    "__v" : 0
}

/* 4 */
{
    "_id" : ObjectId("5d481cd098ba991c0857952f"),
    "name" : "anacito",
    "updatedAt" : ISODate("2019-08-05T12:10:56.777Z"),
    "__v" : 0
}

database :

/* 1 */
{
    "_id" : ObjectId("5d4979d52a17d10a6c8de81b"),
    "components" : [ 
        ObjectId("5d481cd098ba991c0857951f"), 
        ObjectId("5d481cd098ba991c0857952f"), 
        ObjectId("5d481cd098ba991c0857953f"), 
        ObjectId("5d481cd098ba991c0857959f")
    ]
}

Uitvoer:

/* 1 */
{
    "_id" : ObjectId("5d4979d52a17d10a6c8de81b"),
    "components" : [ 
        ObjectId("5d481cd098ba991c0857951f"), 
        ObjectId("5d481cd098ba991c0857952f"), 
        ObjectId("5d481cd098ba991c0857953f"), 
        ObjectId("5d481cd098ba991c0857959f")
    ],
    "dbComponentsArray" : [ 
        {
            "_id" : ObjectId("5d481cd098ba991c0857959f"),
            "name" : "antracito",
            "updatedAt" : ISODate("2019-08-05T12:10:56.777Z"),
            "__v" : 0
        }, 
        {
            "_id" : ObjectId("5d481cd098ba991c0857951f"),
            "name" : "antracito",
            "updatedAt" : ISODate("2019-08-05T12:10:56.777Z"),
            "__v" : 0
        }
    ]
}