[BUG][Typescript][Axios/Fetch] Wrong generated code for array of items using FormData (multipart/form-data)

[jeandonaldroselin]

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• Have you provided a full/minimal spec to reproduce the issue?
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Description

I use open api spec 3 to define api to define two attributes :

• mediasToAdd which is an array of files to upload

• mediasToDelete which is an array of files uuids to delete

---

I use a Typescript Axios in one project and Typescript Fetch in another project,

Theses projects are consuming almost the same (PHP) API endpoints.

But the typescript-axios and typescript-fetch generators generates a code that does not build properly theses array attributes.

This is the generated code :

# For typescript axios
formParams.append('mediasToAdd', element as any);
formParams.append('mediasToDelete', element as any);
# For typescript fetch
localVarFormParams.append('mediasToAdd', element);
localVarFormParams.append('mediasToDelete', element);

This parameters is not considered as array when submitting to a PHP API.

But it should be :

# For typescript axios
formParams.append('mediasToAdd[]', element as any);
formParams.append('mediasToDelete[]', element as any);
# For typescript fetch
localVarFormParams.append('mediasToAdd[]', element);
localVarFormParams.append('mediasToDelete[]', element);

the consequence is that on API side theses values are received as simple attributes instead as arrays.

---

Following the previous screenshot the API will receive :

• mediasToAdd as a single binary (latest value provided)

• mediasToDelete as a single string (latest value provided)

openapi-generator version

I use exactly @openapitools/openapi-generator-cli@1.0.18-5.0.0-beta2

OpenAPI declaration file content or url

Generation Details

Steps to reproduce

Related issues/PRs

Suggest a fix

The problem is located in theses files =>

• https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/typescript-axios/apiInner.mustache
• https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/resources/typescript-fetch/apis.mustache