Mongoose push item to array if exists

Question

I have a model schema like this :

favMovieSchema = mongoose.Schema({
    movieId: {type: mongoose.SchemaTypes.ObjectId, ref: "Movie"},
    rating: [{
        type: Number,
        // trim:true,
        //MinMax validator
    }],
});
    movieSchema={
          some fields,
          favMovies: [favMovieSchema],
        }

I want to push a rating into rating column if movieId already exists, to maintain a history of ratings done by a particular user. If it does not exists I am simply updating a new object with no issue.

I need some complex mongoose query to help me make a check for this.

Answer 1

It sounds like the complex query you need is:

collection.update({movieId: movieId}, {$push: {rating: rating}}, {upsert: true})

The first part is the matching: you are looking for a document with this movieId. The 2nd part is the update: pushing one more rating to the rating array. The 3rd part is the options, upsert meaning update if the matching exist and create a new document if it does not.