MongoDB group performance in node.js

Question

MongoDB group performance in node.js

As a preface, I'm using Node.js with Mongo-db-native.

I'm also using GridFS to store images and each image has meta data, one of which is a Product Id.

I want to query all the the fs.files and return images that are associated to a specific product.

Here's how I am currently doing this:

this.collection.ensureIndex({
    product_id: 1,
}, function (err, edIndex) {
    self.collection.group(   ['group'] , {
        "product_id": ObjectID(product_id)
    } , {
        docs: []
    } , function (doc, prev) {
        prev.docs.push({
            width: doc.width,
            height: doc.height,
            _id: doc._id
        });
    } , true , function (err, results) { 
        if (err) {
            callback(err)
        } else {
            callback(null, results)
        } 
    });
});

I'm finding that this is extremely slow. Does anyone have any suggestions as an alternative or how to increase the performance of this?

Thank you!

database
node.js
mongodb

Answer 1

Here is a simple query in Mongo shell syntax which will find all GridFS files with ProductId = 42 in its metadata.

db.fs.files.find({"metadata.ProductId": 42});

The returned documents will contain a filename which can be used with mongo-native's GridStore.