How to do advance filter and sort ( E-commerce ) using Firestore

Question

I am trying to build an E-commerce app using firebase firestore, i am stuck at filtering and and sorting the product on user input. I am able to apply all filter and sort but I

Answer 1

Cloud Firestore queries are immutable. If you try to change the value by calling for example:

.where('color', '==', colorSelected)

Your query simply becomes a new query. To solve this, you have to create a reference to the allProducts collection and then add a new filter, according to what the user has selected. This is an example:

const db = firebase.firestore();
const allProductsRef = db.collection("allProducts");
const basicQuery;
if(userHasSelectedColor) {
    basicQuery = allProductsRef.where('color', '==', colorSelected);
} else if (userHasSelectedColorAndCategory) {
    basicQuery = allProductsRef.where('color', '==', colorSelected)
                    .where('category', 'array-contains-any', keyword);
}

In this way, you can chain as many function calls as you need.