@ApiHeader() schema is being overwritten if an enum is provided

[jointhejourney]

Is there an existing issue for this?

• I have searched the existing issues

Current behavior

Using the following @ApiHeader() with an enum:

  @ApiHeader({
    name: 'Journey-Version',
    description: 'API version',
    enum: ['1'],
    schema: {
      default: '1',
    }
  })

Generates the following OpenAPI schema:

 /test:
    post:
      operationId: TestController_testRequest
      parameters:
        - name: Journey-Version
          in: header
          description: Journey API version.
          required: false
          schema:
            enum:
              - '1'
            type: string

Minimum reproduction code

https://gist.github.com/jointhejourney/13b4cd7feba0864f11c8fd42fd069890

Steps to reproduce

No response

Expected behavior

It should include the default value as provided by the schema, such as:

 /test:
    post:
      operationId: TestController_testRequest
      parameters:
        - name: Journey-Version
          in: header
          description: Journey API version.
          required: false
          schema:
            type: string
            enum:
              - '1'
            default: '1'

Package version

7.1.10

NestJS version

9.3.9

Node.js version

18.19.0

In which operating systems have you tested?

• macOS
• Windows
• Linux

Other

This seems to be a fairly straightforward fix, the schema is being overwritten here if an enum is provided:

swagger/lib/decorators/api-header.decorator.ts

Lines 36 to 42 in 5108ba6

	if (options.enum) {
	const enumValues = getEnumValues(options.enum);
	param.schema = {
	enum: enumValues,
	type: getEnumType(enumValues)
	};
	}

Maybe we can do it like this?

  if (options.enum) {
    const enumValues = getEnumValues(options.enum);
    param.schema = {
+     ...param.schema,
      enum: enumValues,
      type: getEnumType(enumValues)
    };
  }

This way, if a default value is provided in the schema object, it won't be ignored. This is a not a huge issue since I can just provide the enum directly into the schema, but if my suggestion makes sense, I could submit a PR. Thanks!

[alenap93]

Your solution seems to be a good fix

[kamilmysliwiec]

Would you like to create a PR for this issue?