Remove fields from typescript interface object

Question

I am getting a json response and storing it in mongodb, however the fields that I don\'t need are also getting in to the database, is there anyway to strip the uneseccary fi

Answer 1

If you want to do this in a strongly-typed way, you can define a dummy/ideal object which satisfies your interface (const dummy: IMyInterface = {someField: "someVal"};), and then filter incoming objects' fields against Object.keys(dummy). This way your compiler will complain if you update the interface without updating this 'filtering' code.

Answer 2

You can use a function that picks certain properties from a given object:

function pick<T, K extends keyof T>(obj: T, ...keys: K[]): Pick<T, K> {
    const copy = {} as Pick<T, K>;

    keys.forEach(key => copy[key] = obj[key]);

    return copy;
}

Then:

let obj = { "name": "someName", "age": 20 };
let copy = pick(obj, "name") as Test;
console.log(copy); // { name: "someName" }

Answer 3

Suppose you want to remove age

temp = {...temp, age: undefined}

This will remove age from your object for good.