Support generic type parameter and return type about tsoa

[nenadalm]

I see that support for this was merged, but if I try to use Promise<ResultList<Resource>> I get an error:

$ ./node_modules/.bin/tsoa swagger
There was a problem resolving type of 'T'.
There was a problem resolving type of 'ResultListResource'.
Error: No matching model found for referenced type T

with ResultList being

interface ResultList<T> {
    data: T[],
}

version: [email protected]

[andriykrasnychuk]

+1

[fhewitt]

That's absolutely awesome. I love it!

But still have similar issue adding extends

export interface ThingContainerWithTitle extends GenContainer<TheThing> {
    title: string;
}

export interface GenContainer<T> {
    id: string;
    list: T[];
}

And I got

There was a problem resolving type of 'T'.
There was a problem resolving type of 'GenContainer'.
There was a problem resolving type of 'ThingContainerWithTitle'.

[janhrastnik]

@mrgoonie I had the exact same issue today, the problem is that the return type of getMessage() isn't explicitly typed.

@Get()
async getMessage() {
	const data: PingEntity = { message: "pong" };
	let result: ResponseObject<PingEntity> = { status: 1, data };
	return result;
}

Should be changed to:

@Get()
async getMessage(): Promise<ResponseObject<PingEntity>> {
	const data: PingEntity = { message: "pong" };
	let result: ResponseObject<PingEntity> = { status: 1, data };
	return result;
}

[lukeautry]

I think this can be supported and it's a great idea. I'll look into it soon.

[judenaveenraj]

@nenadalm +1 same here

[judenaveenraj]

Just something i came across while fiddling with the above
The following seems to work:
interface ResultList {
data: T,
}

The following doesn't, gives the above error that @nenadalm mentioned:
interface ResultList {
data: T[],
}
The following doesn't as well
interface ResultList {
data: Array,
}

[AndyGura]

+1 on this! I can't make something like

export interface IListPage<T> {
    pageIndex: number;
    totalPages: number;
    list: T[];
}

And use as result Promise<IListPage<MyCoolItem>>

[amozh-op]

+1, i have the same issue

[AndyGura]

@lukeautry Hello, anytning on this? Its been sitting there dormant for a while

[fhewitt]

+1, same issue here. This seems a particularly important feature for code maintenance.

[ChamNouki]

Hello, still have a kind a similar issue :

There was a problem resolving type of 'T'.
There was a problem resolving type of 'JsonApiResourceT'.
There was a problem resolving type of 'JsonApiWrapperUserAttributes'.
Generate routes error.
 Error: No matching model found for referenced type T.
    at new GenerateMetadataError (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/exceptions.js:17:28)
    at getModelTypeDeclaration (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:419:15)
    at getReferenceType (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:280:25)
    at resolveType (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:95:25)
    at /Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:496:23
    at Array.map (<anonymous>)
    at getModelProperties (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:462:14)
    at getReferenceType (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:281:26)
    at resolveType (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:92:25)
    at resolveType (/Users/thibaut/Documents/poc/jsonapi-serializer/node_modules/tsoa/dist/metadataGeneration/resolveType.js:69:30)

I use tsoa in version 2.1.4.

Here is my controller :

@Route("users")
export class UsersController extends Controller {
    @Get("{id}")
    public async getUser(
        @Path("id") id: number,
        @Query() name?: string
    ): Promise<JsonApiWrapper<UserAttributes>> {
        const user = await UserService.get(id);
        return SerializerService.serialize(user);
    }

    @SuccessResponse("201", "Created")
    @Post()
    public async createUser(
        @Body() requestBody: UserCreationRequest
    ): Promise<JsonApiWrapper<UserAttributes>> {
        const user = await UserService.create(requestBody);
        this.setStatus(201); // set return status 201
        return SerializerService.serialize(user);
    }
}

and my Models :

User.ts

export interface User extends UserAttributes {
    apiId: number;
}

export interface UserAttributes {
    email: string;
    name: Name;
    status?: Status;
    phoneNumbers: string[];
}

export type Status = "Happy" | "Sad";

export interface Name {
    first: string;
    last?: string;
}

export interface UserCreationRequest {
    email: string;
    name: Name;
    phoneNumbers: string[];
}

JsonApiWrapper.ts

export interface JsonApiWrapper<T> {
    data?:
        | JsonApiResource<T>
        | Array<JsonApiResource<T>>
        | JsonApiResourceIdentifier
        | JsonApiResourceIdentifier[]
        | null;
    error?: JsonApiError[];
    meta?: JsonApiMeta;
    jsonapi?: any;
    links?: JsonApiWrapperLinks;
    included?: Array<JsonApiResource<T>>;
}

JsonApiError.ts

export interface JsonApiError {
  id?: string;
  links?: JsonApiErrorLinks;
  status?: string;
  code?: string;
  title?: string;
  detail?: string;
  source?: JsonApiErrorSource;
}

export interface JsonApiErrorSource {
    pointer: string;
    parameter: string;
    meta: JsonApiMeta;
}

JsonApiMeta.ts

export interface JsonApiMeta {
    [key: string]: any;
}

JsonApiResource.ts

export interface JsonApiResource<T> {
    type: string;
    id?: string;
    attributes?: T;
    relationships?: JsonApiRelationships;
    links?: JsonApiResourceLinks;
    meta?: JsonApiMeta;
}

export interface JsonApiResourceIdentifier {
    type: string;
    id: string;
    meta?: any;
}

JsonApiRelationships.ts

export interface JsonApiRelationships {
    [key: string]: JsonApiRelationship;
}

export interface JsonApiRelationship {
    links: JsonApiLinks;
    data: JsonApiResourceIdentifier | JsonApiResourceIdentifier[] | null;
}

JsonApiLinks.ts

export interface JsonApiLinks {
  self?: string | JsonApiLinkObject;
  related?: string | JsonApiLinkObject;
  [key: string]: string | JsonApiLinkObject;
}

export interface JsonApiLinkObject {
  href: string;
  meta: any;
}

export interface JsonApiResourceLinks extends JsonApiLinks {
  self: string | JsonApiLinkObject;
  related: string | JsonApiLinkObject;
}

export interface JsonApiErrorLinks extends JsonApiLinks {
  about: string | JsonApiLinkObject;
}

export interface JsonApiWrapperLinks extends JsonApiLinks {
  first?: string | JsonApiLinkObject;
  last?: string | JsonApiLinkObject;
  prev?: string | JsonApiLinkObject;
  next?: string | JsonApiLinkObject;
}

any update on this issue ?

[ChamNouki]

So I tried to replace some generic parts of my interface and the following interface replacing JsonApiWrapper seems to work :

JsonApiUser.ts

export interface JsonApiUser {
    data?:
        | JsonApiResource<UserAttributes>
        | Array<JsonApiResource<UserAttributes>>
        | JsonApiResourceIdentifier
        | JsonApiResourceIdentifier[]
        | null;
    error?: JsonApiError[];
    meta?: JsonApiMeta;
    jsonapi?: any;
    links?: JsonApiWrapperLinks;
    included?: Array<JsonApiResource<UserAttributes>>;
}

I think it's the passing on of the generic type to another generic interface that bring on the issue.

[mazswojejzony]

Bump. Any plans to fix this?

[lukeautry]

This is definitely a desirable feature but it's some work to implement it handle all of the cases.

[dgreene1]

Full support for generics was added in v2.4.10.

[ryankeener]

@dgreene1 I think this should be re-opened as I'm still seeing the behavior described above.

It can be replicated by replacing

tsoa/tests/fixtures/testModel.ts

Lines 360 to 363 in ac71d13

	export interface GenericRequest<T> {
	name: string;
	value: T;
	}

with

export interface GenericRequest<T> {
  name: string;
  value: T;
  nested?: GenericNested<T>;
}

export interface GenericNested<T> {
  foo: T;
}

and re-running the tests:

There was a problem resolving type of 'T'.
There was a problem resolving type of 'GenericNestedT'.
There was a problem resolving type of 'GenericRequestTypeAliasModel1'.
There was a problem resolving type of 'GenericRequestGenericRequestTypeAliasModel1'.
There was a problem resolving type of 'TestModel'.

[dgreene1]

@ryankeener I know you already confirmed that this works, but I wanted to let you know that this fix/feature was just released in v2.5.1. Can you let us know how it worked out for you?

Side note: we're looking for companies that want to be featured in tsoa's readme: #464

[dgreene1]

@fhewitt would you be so kind as to make a separate issue for that scenario since the non-extended generic scenarios seem to be resolved?

[fhewitt]

Can do that! > #467

[mrgoonie]

Hi @WoH @dgreene1, sorry for digging this but I think this issue isn't fully resolved (or maybe I'm doing something incorrectly).

import { Get, Route } from "tsoa";

interface ResponseObject<T> {
	status: number;
	data: T | any;
}

interface PingEntity {
	message: string;
}

@Route("ping")
export default class PingController {
	@Get()
	async getMessage() {
		const data: PingEntity = { message: "pong" };
		let result: ResponseObject<PingEntity> = { status: 1, data };
		return result;
	}
}

When I try to generate the swagger json it throws this error:

There was a problem resolving type of 'ResponseObject<any>'.
Generate swagger error.
 Error: Debug Failure. False expression: Node must have a real position for this operation

But when I specified the type directly to ResponseObject (instead of using generic type), it will works normally:

interface ResponseObject {
	status: number;
	data: PingEntity;
}

Here is the example repo: https://github.com/mrgoonie/express-swagger-typescript

---

Temporary workaround solution:

import { Get, Route } from "tsoa";

// no generic type
interface ResponseObject {
	status: number;
	data: any;
}

interface PingEntity {
	message: string;
}

@Route("ping")
export default class PingController {
	@Get()
	async getMessage() {
		const data: PingEntity = { message: "pong" };
		// use type combination instead of generic type
		let result: ResponseObject & { data: PingEntity } = { status: 1, data };
		return result;
	}
}

---

Cheers,