[BUG] [typescript-fetch] Incorrect parsing with additional properties

[ArshadRao]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?

Description

The typescript-fetch generator doesn't parse the request object correctly when the content type is multipart/form-data and object has additional properties.

openapi-generator version

openapi-generator version 7.10.0

https://gist.github.com/ArshadRao/9ecbfbbb14c09927e0b078fd32e0dfcb

generated output

Issue in the generation

Generating unexpected typescript code to parse the request parameters on line 87, resulting in error for the whole file.

Generation Details

{ "withInterfaces": true, "enumPropertyNaming": "original" }

Steps to reproduce

openapi-generator-cli generate -i ./swagger.json -g typescript-fetch

[DavidGrath]

@ArshadRao does this still affect you? Do you have any workarounds or are you still stuck with this?

[ArshadRao]

@DavidGrath This still affects my work, the only workaround I have for now is to manually update it and apply git patch to it.

[DavidGrath]

@ArshadRao another workaround I've seen for now is to set withoutRuntimeChecks to true, though that still seems just as bad. I'm still looking into this before I loop in Leon Yu, the author of the template

[DavidGrath]

openapi-generator/modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache

Line 268 in 45aeae3

formParams.append('{{baseName}}', new Blob([JSON.stringify({{{dataType}}}ToJSON(requestParameters['{{paramName}}']))], { type: "application/json", }));

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractTypeScriptClientCodegen.java

Line 654 in 45aeae3

return "{ [key: string]: " + getTypeDeclaration(unaliasSchema(inner)) + nullSafeSuffix + "; }";

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractTypeScriptClientCodegen.java

Line 673 in 45aeae3

return "{ [key: string]: " + this.getParameterDataType(parameter, inner) + "; }";

@leonyu Hello, I see that you're the author of the Typescript-Fetch template, so please let me know if it's you or someone else I should ask about this.
I don't know a lot about Typescript, but it seems that the main issue has to do with Index Signatures.
Is there some property in CodegenProperty or ExtendedCodegenProperty that can be used to prevent this?

[DavidGrath]

@kota65535 Hello, I'm looping you in because I see you've recently committed to the template. Please do you have any insight as to how TypeScript Index Signatures should work concerning this bug?

[DavidGrath]

@ArshadRao sorry for the long wait. I think I've fixed it now, just waiting for a review