mapSet

mapSet allows you to set the update value using a method. This is helpful in case where you want to update the value using some logic.

It is a function which is called with two parameter - setValue & storedValue.

Let's create a method which sets the total price -

function myUpdateMapper(setValue, storedValue){
   setValue.totalPrice = storedValue.price * storedValue.quantity;
}

We have created the method, now we need to tell jsstore to use this method in update query -

With web worker

In case of web worker, you first need to make your method accessible to jsstore worker, so that it can call it.

1. Save the above code in a file and import it inside web worker

you can use importScripts to import your scripts which contains your methods.

await connection.importScripts("update_logic.js");

2. Use the method in query

connection.update({
    in:"Products",
    set:{
        totalPrice:0
    },
    mapSet: 'myUpdateMapper' // pass the method name
})

Without web worker

You can simply use the method as mapSet.

connection.update({
    in:"Products",
    set:{
        totalPrice:0
    },
    mapSet: myUpdateMapper // pass the method
})