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• 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?
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Description

scala-sttp client generator doesn't generate doesn't generate Api properly when the request header is not a string.

openapi-generator version

The both version 6.0.0 and the latest master branch (6.0.x)

OpenAPI declaration file content or url

openapi: 3.0.0
info:
  title: Request Header
  version: "1.0.0"
paths:
  /test:
    get:
      summary: Empty Route
      parameters:
      - description: Gets user uuid.
        explode: false
        in: header
        name: user_uuid
        required: true
        schema:
          format: uuid
          type: string
        style: simple
      responses:
        "200":
          description: Good Request.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ReturnValue'
        "400":
          description: Bad Request.
components:
  schemas:
    ReturnValue:
      properties:
        name:
          type: string

Generation Details

Command line used for generation

openapi-generator-cli generate \
  -g scala-sttp \
  -i name_of_file.yaml \
  -p mainPackage=myPackage \
  -o myApi

Steps to reproduce

Generated class DefaultApi

  def rootGet(userUuid: UUID): Request[Either[ResponseException[String, Exception], ReturnValue], Nothing] =
    basicRequest
      .method(Method.GET, uri"$baseUrl/test")
      .contentType("application/json")
      .header("user_uuid", userUuid)
      .response(asJson[ReturnValue])

Compile Error:

DefaultApi.scala:39:8: overloaded method header with alternatives:
[error]   (k: String,ov: Option[String])sttp.client3.RequestT[sttp.client3.Identity,Either[String,String],Any] <and>
[error]   (k: String,v: String)sttp.client3.RequestT[sttp.client3.Identity,Either[String,String],Any] <and>
[error]   (h: sttp.model.Header,replaceExisting: Boolean)sttp.client3.RequestT[sttp.client3.Identity,Either[String,String],Any]
[error]  cannot be applied to (String, java.util.UUID)
[error]       .header("user_uuid", userUuid)
[error]        ^

Related issues/PRs

Suggest a fix

The generator should convert the value of header parameter to string.