Using mongoose $inc in array of subdocuments

Question

I need to implement a functionality where every product posted will increase product counts of respective category and subcategory. This is my schema:

//Subcategory
const subcategorySchema = new mongoose.Schema({
    title: {type: String},
    productsCounts: {type: Number, default: 0},
});

//Category
const categorySchema = new mongoose.Schema({
    title: {type: String},
    subcategories: [subcategorySchema],
    productsCounts: {type: Number, default: 0}
});

//Method I use to update products count
categorySchema.statics.increaseProductsCounts = function (categoryId, subcategoryId) {
    //Increase category's productCounts.
    this.findByIdAndUpdate(categoryId, {$inc: {productsCounts: 1}}).then(r => {
        console.log(r)
    });
};

The above code works for category productCounts well. How can update specific subcategory productCounts too?

I am beginner To mongoDb and mongoose. That question didnt help — Nux, Mar 17 '19 at 11:22

score 0 · Accepted Answer · answered Mar 16 '19 at 21:38

0

You can use the filtered positional operator (MongoDB 3.6 or newer) to define a condition which will identify your subcategory:

categorySchema.statics.increaseProductsCounts = function (categoryId, subcategoryId) {
    this.findByIdAndUpdate(categoryId, 
        {$inc: {productsCounts: 1, 'subcategories.$[sub].productsCounts': 1}}, 
        { arrayFilters:[ { 'sub._id': subcategoryId } ] }).then(r => {
            console.log(r);
    });
};

answered Mar 16 '19 at 21:38

mickl

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Thanks for response. I have copied and pasted the above code in my project but only productsCounts in **Category** increases and not in specific subcategory. Here is the log i get `{ productsCounts: 108, _id: 5c8ab97c4835f2316811d41d, title: 'Guests', subcategories: [ { productsCounts: 0, properties: [], _id: 5c8ab99d4835f2316811d41e, title: 'Bondeni' }, { productsCounts: 0, properties: [], _id: 5c8ab9ba4835f2316811d420, title: 'Tema' } ], __v: 0 }` – Nux Mar 17 '19 at 11:19
What could still be wrong? – Nux Mar 17 '19 at 11:20
After updating mongoose version to latest it now works. Thanks for – Nux Mar 17 '19 at 12:20
can you take a look at my other question. they are kind related. [link](https://stackoverflow.com/questions/55217447/mongoose-upsert-and-inc-subdocument) @mickl – Nux Mar 18 '19 at 14:29

Using mongoose $inc in array of subdocuments

1 Answers1