Typescript, define a generic instead object

Question

Currently I have this interfaces:

export interface requestPayload {
  agentId: string;
}

export interface Agent {
  id: string;
  name: string;
  requestPayload: requestPayload;
}

My problem is requestPayload property of Agent interface is now an object with { agentId: string; }

But requestPayload should be anything, like an array, number, string, and maybe that object that I defined with requestPayload interface.

I got a suggestion to "use a generic", how can I change that to a generic? I'm not sure how to proceed.

Why make a requestPayload interface in the first place if requestPayload doesn't have to match the type? — Aplet123
– Aplet123, Commented Dec 12, 2020 at 19:02
At first I thought that requestPayload would be always an object, but now it seems that can be anything, so how can define it's type? — pmiranda
– pmiranda, Commented Dec 12, 2020 at 19:04

Anatoly · Accepted Answer · 2020-12-12 19:07:27Z

1

Using generics is quite right solution for your case:

export interface Agent<T> {
  id: string;
  name: string;
  requestPayload: T;
}

answered Dec 12, 2020 at 19:07

Anatoly

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2 Comments

Thanks, I was posting that as a solution because I wasn't sure if it was correct

Depends on your tasks and goals. If you wish to shape every instance of Agent that this solution is for you

Brother Woodrow · Accepted Answer · 2020-12-12 19:05:53Z

0

You can use unknown:

export interface Agent {
  id: string;
  name: string;
  requestPayload: unknown;
}

As the docs indicate, it was meant for this sort of thing.

answered Dec 12, 2020 at 19:04

Brother Woodrow

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That's a solution but I can't, the Eslint config for this project doesn't allow any types.

Ok, with unknown I have other eslint problems, when I want to acces a propery of an object it says that it's not possible on unknown type