cache.identify : Index signature is missing in type

related to

#6083

Intended outcome:

I want to retrieve the Apollo Client cache ID for a particular object.

interface MyMapInterface {
  __typename: "Map";
  id: string;
  width: number;
  height: number;
}

const myMap: MyMapInterface = { __typename: "Map", id: "1", width: 100, height: 100 };

client.cache.identify(myMap);

Actual outcome:

I get the following TS error.

Argument of type 'MyInterface' is not assignable to parameter of type 'StoreObject | Reference'.
  Type 'MyInterface' is not assignable to type 'StoreObject'.
    Index signature is missing in type 'MyInterface'.

How to reproduce the issue:

Playground

Versions

  System:
    OS: Windows 10 10.0.19041
  Binaries:
    Node: 15.5.1 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.10 - ~\Documents\workspace\GOunite\v3\client\node_modules\.bin\yarn.CMD
    npm: 6.14.10 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Chrome: 87.0.4280.88
    Edge: Spartan (44.19041.423.0), Chromium (87.0.664.75)
  npmPackages:
    @apollo/client: 3.3.6 => 3.3.6
    @apollo/link-context: 2.0.0-beta.3 => 2.0.0-beta.3
    @apollo/link-error: 2.0.0-beta.3 => 2.0.0-beta.3
    @apollo/link-persisted-queries: 1.0.0-beta.0 => 1.0.0-beta.0
    @apollo/link-ws: 2.0.0-beta.3 => 2.0.0-beta.3
    @apollo/react-testing: 3.1.4 => 3.1.4
    apollo: 2.32.1 => 2.32.1
    apollo-cache-persist: 0.1.1 => 0.1.1
    apollo-upload-client: 14.1.0 => 14.1.0

TS 4.1

[rylanc]

The same issue exists if the interface passed is generated by the Apollo CLI (e.g. using an object returned in the data of a mutation). For best compatibility between Apollo created tools, it seems like changing the parameter type might be the best fix.

[PeterDekkers]

It’s possible to circumvent the issue by using spread syntax.

client.cache.identify({ ...myMap });

Although this could affect performance. Personally I prefer to @ts-ignore the warning.

There is a related issue in the Typescript repo.