like/dislike mongodb using bulk - mongodb

Question

let bulk = Card.collection.initializeOrderedBulkOp();
// if user doesn't exist in array
bulk.find({
'_id': mongoose.Types.ObjectId(card_id),
'likedBy': { '$ne': mongoose.Types.ObjectId(user_id) }
}).updateOne({
'$inc': { 'likes': 1 },
'$push': { 'likedBy': mongoose.Types.ObjectId(user_id) }
});
// if user exists in array
bulk.find({
"_id": mongoose.Types.ObjectId(card_id),
"likedBy": mongoose.Types.ObjectId(user_id)
}).updateOne({
"$inc": { "likes": -1 },
"$pull": { "likedBy": mongoose.Types.ObjectId(user_id) }
});
bulk.execute(function(response) {
console.log(response);
return res.json({
'state': true,
'msg': 'Successful',
})
});
The above is supposed to behave by incrementing or decrementing the likes field if the user id exists in the likedBy array.
However, both functions run, thus the last of the bulk gets to be the last action done. In the above, the end result is always zero.
I suspect the query matches a document always, thus the .updateOne() parts run on all.
Here's the schema:
var CardSchema = new Schema({
slug: {
type: String,
lowercase: true,
index: true
},
title: String,
content: String,
createdAt: {
type: Date,
default: Date.now,
},
updatedAt: {
type: Date,
},
options: [],
likedBy: [],
likes: Number,
createdBy: String,
featured: Boolean,
});
Is there a better mongo way to do the like/dislike thing?

Answer 1

Going with this for now. Too verbose, but works. I've created a like and dislike button separately in the UI, which calls two independent functions, but to same endpoint, with endpoint rigged like this:
let like = req.body.like;
// if request is a like
if (like) {
Card.update({
'_id': mongoose.Types.ObjectId(card_id),
'likedBy': { '$ne': mongoose.Types.ObjectId(user_id) }
}, {
'$inc': { 'likes': 1 },
'$push': { 'likedBy': mongoose.Types.ObjectId(user_id) }
}, function(err) {
if (err) {
console.log(err);
return res.json({
'state': false,
'msg': err
})
}
return res.json({
'state': true,
'msg': 'Liked',
})
})
} else if (!like) { // if request is dislike
Card.update({
'_id': mongoose.Types.ObjectId(card_id),
'likedBy': mongoose.Types.ObjectId(user_id)
}, {
'$inc': { 'likes': -1 },
'$pull': { 'likedBy': mongoose.Types.ObjectId(user_id) }
}, function(err,) {
if (err) {
console.log(err);
return res.json({
'state': false,
'msg': err
})
}
return res.json({
'state': true,
'msg': 'Disliked',
})
})
}
Then something like this makes the request,
likeCard(card_id: string, like: boolean) {
let param = {
card_id: card_id,
like: like
};
return this.http.post(AppSettings.API_ENDPOINT + '/card/like', JSON.stringify(param), { headers: this.headers })
.map((res) => {
return res
})
}