[BUG] [typescript] not compatible with --isolatedModules

[bard]

Bug Report Checklist

• [x] Have you provided a full/minimal spec to reproduce the issue?
• [x] Have you validated the input using an OpenAPI validator (example)?
• [x] What's the version of OpenAPI Generator used?
• [x] Have you search for related issues/PRs?
• [x] What's the actual output vs expected output?
• [ ] [Optional] Bounty to sponsor the fix (example)

Description

Using the new TypeScript generator from #6341

The generated code is not compatible with --isolatedModules, which is required by popular setups such as create-react-app.

openapi-generator version

5.0.0-SNAPSHOT

OpenAPI declaration file content or url

https://github.com/bard/repro-openapi-generator-typescript-isolated-modules/blob/master/example.yaml

Command line used for generation

OPENAPI_GENERATOR_VERSION=5.0.0-SNAPSHOT /tmp/openapi-generator-cli.sh generate -g typescript -i example.yaml -o ./src/api

Steps to reproduce

1. git clone https://github.com/bard/repro-openapi-generator-typescript-isolated-modules/blob/master/example.yaml
2. OPENAPI_GENERATOR_VERSION=5.0.0-SNAPSHOT /tmp/openapi-generator-cli.sh generate -g typescript -i example.yaml -o ./src/api
3. yarn && yarn start

Failed to compile.

/tmp/repro-openapi-generator-typescript-isolated-modules/src/api/index.ts
TypeScript error in /tmp/repro-openapi-generator-typescript-isolated-modules/src/api/index.ts(4,31):
Cannot re-export a type when the '--isolatedModules' flag is provided.  TS1205

    2 | export * from "./auth/auth";
    3 | export * from "./models/all";
  > 4 | export { createConfiguration, Configuration } from "./configuration"
      |                               ^
    5 | export * from "./apis/exception";
    6 | export * from "./servers";
    7 | 

Related issues/PRs

https://github.com/facebook/create-react-app/issues/6054

Suggest a fix

Possible workaround is to export * from index.ts:

  export * from "./http/http";
  export * from "./auth/auth";
  export * from "./models/all";
- export { createConfiguration, Configuration } from "./configuration"
+ export * from "./configuration"
  export * from "./apis/exception";
  export * from "./servers";

[auto-labeler[bot]]

👍 Thanks for opening this issue! 🏷 I have applied any labels matching special text in your issue.

The team will review the labels and make any necessary changes.

[rsp]

It's been over two years since this bug is open. Are there any plans to fix it?

A temporary workaround for anyone who is waiting for the fix:

• use typescript-eslint
• set @typescript-eslint/consistent-type-exports rule to "error"
• run eslint --fix on the code generated by openapi-generator

Hopefully it won't be needed soon but meanwhile this can be used to fix the code automatically.

[Drago92]

Now the Issue has been fixed and the configuration Type has the right export:

export * from "./http/http";
export * from "./auth/auth";
export * from "./models/all";
export { createConfiguration } from "./configuration"
export type { Configuration } from "./configuration"
export * from "./apis/exception";
export * from "./servers";
export { RequiredError } from "./apis/baseapi";

export { PromiseMiddleware as Middleware } from './middleware';

But in the same file the PromiseMiddleware Type has the wrong export:

[wing328]

export { PromiseMiddleware as Middleware } from './middleware';

I wonder if you can file a PR to fix it 🙏

[Drago92]

export { PromiseMiddleware as Middleware } from './middleware';

I wonder if you can file a PR to fix it 🙏

Okay a PR is not necessary. I took a look at the code and i saw that the export type will be set when the addditional property platform=deno is set. For example: openapi-generator generate -g typescript -i ./schema.yaml -o ./Client --additional-properties=platform=deno

Output-File:

[Drago92]

export { PromiseMiddleware as Middleware } from './middleware';

I wonder if you can file a PR to fix it 🙏

Okay a PR is not necessary. I took a look at the code and i saw that the export type will be set when the addditional property platform=deno is set. For example: openapi-generator generate -g typescript -i ./schema.yaml -o ./Client --additional-properties=platform=deno

Output-File:

Nevermind. The deno Version is not compatible with node. I will create a PR