Impossible 'body' field required in GET

[gtrak]

Description

I'm seeing an issue where generated typescript types result in some impossible types:

Type error: Argument of type '{ params: { path: { id: string; }; }; }' is not assignable to parameter of type 'FetchOptions<{ parameters: { path: { id: string; }; }; responses: ...snipped
  Property 'body' is missing in type '{ params: { path: { id: string; }; }; }' but required in type '{ body: never; }'.

  10 |
  11 | async function exampleGet() {
> 12 |   const { data, error } = await get(`/v1/endpoint`, {
     |                                                                             ^
  13 |     params: { path: { id: "todo" } },
  14 |   });
  15 | }

I am able to work around it by adding a field body: "" as never, which seems to be forcing TS into the right path. body: undefined or body: null does not work either.

Reproduction

I used the latest versions of openapi-fetch, openapi-typescript, and an internal OpenAPI spec with only GETs in it.

Something relevant in the generated code seems to be:

export interface components {
...
  responses: never;
  parameters: never;
  requestBodies: never;  // <--
  headers: never;
  pathItems: never;
}

Expected result

I can work out the types in this scenario more easily.

Checklist

• I’m willing to open a PR (see CONTRIBUTING.md)

[drwpow]

Edit: I didn’t know you could transfer issues!

[vdawg-git]

I am getting the same issue. However when I try to do something like:

{ body: '' as never }

I get a runtime error: TypeError: Failed to execute 'fetch' on 'Window': Request with GET/HEAD method cannot have body.

Not sure how to circumvent that without disabling typechecking.

[kepek]

Up

[gtrak]

body: undefined as never is able to issue requests

[jiroscripts]

Same issue here

[drwpow]

I think some of this may be fixed in 0.6.0 by a looser parsing of the media type.

If anyone is having issues in 0.6.0, a reproduction would be helpful with a short snippet of the OpenAPI schema you’re using 🙏

[t1mmen]

@drwpow I'm also having this exact issue on (every) GET requests on openapi-fetch@0.6.0 (types generated with openapi-typescript@6.2.8)

error TS2345: Argument of type '{ params: { query: { connectionId: number; }; path: { provider: string; operationId: string; }; }; }' is not assignable to parameter of type 'FetchOptions<{ parameters: { query: { connectionId: number; }; path: { provider: string; operationId: string; }; }; responses: { 200: { content: { "application/json": { message?: string; operationsLog?: { jobSummary?: { executionSeconds?: string; executeOperations?: string[]; okCount?: number; errorCount?: number; }...'.
  Property 'body' is missing in type '{ params: { query: { connectionId: number; }; path: { provider: string; operationId: string; }; }; }' but required in type '{ body: never; }'.

body: undefined as never does work. Mind you, vscode does not complain, workaround or not, but tsc does 🤷

I can't share a full spec atm, but the types generated below map to the error above. If I had to bet, this seems like a generic "applies to all GET operations"-kinda issue

export interface paths {
  "/api/1.0/integrations/{provider}/{operationId}?connectionId={connectionId}": {
    get: operations["providerOperationId"];
  };
}

// ...

export interface operations {
  providerOperationId: {
    parameters: {
      query: {
        connectionId: components["parameters"]["connectionIdParam"];
      };
      path: {
        provider: components["parameters"]["providerParam"];
        operationId: components["parameters"]["operationIdParam"];
      };
    };
    responses: {
      200: {
        content: {
          "application/json": components["schemas"]["OperationOutcome"];
        };
      };
      401: components["responses"]["Unauthorized"];
      500: components["responses"]["Error"];
    };
  };
}

(PS: Thank you for making this tool! Bug aside, what I've seen so far is awesome! 👏 )

[djMax]

I'm going to dig into this a bit as we are doing a big migration to openapi-typescript and a openapi-fetch-derived module that uses apollo, and I don't want to have to explain to PR reviewers why body: undefined as never is littered everywhere. Any pointers appreciated, I will report back on progress.