TypeScript: Can I assert a value to a type with different property names?

Question

I am working with an API and a web framework.

I have an interface IResponse. It looks something like this

interface IResponse {
    Id: string;
    Name: string;
}

When I get an API response, I get an array and assert the value as IResponse[]

However, the Web Framework I'm using requires me to convert this IResponse[] to an IComboBoxOption[] which has the following interface:

interface IComboBoxOption {
    key: string;
    text: string;
}

Right now, I am converting it like this:

const convertedResults: IComboBoxOption[] = [];
const results = await APICall(productsRequest) as IResponse[];

results.forEach(r => {
    convertedResults.push({
        key: r.Id,
        text: r.Name,
    });
}

However, there are a large amount of results and the forEach loop takes too long. Ideally, I would like to skip the conversion step all together, and directly assert the API return value as an IComboBoxOption[].

Is this at all possible?

Note: I have no control over the property names returned by the API, and I must use this Web Framework.

Answer 1

There is no way to change the names of the properties without iterating over each value. But you can use a method that has more performance:

Using ES6 array methods tend to work faster https://leanylabs.com/blog/js-forEach-map-reduce-vs-for-for_of/

try using this:

const convertedResults: IComboBoxOptions = results.map((r) => ({
  key: r.Id,
  text: r.Name,
}));