Refresh the browser each time, the global header is added in duplicate.

[doljae]

Describe the bug

• Refresh the browser each time, the global header is added in duplicate.

To Reproduce
Steps to reproduce the behavior:

• Repo: https://github.com/doljae/decalcomanie/tree/feature/swagger
• used version: 1.16.11

SwaggerConfiguration.kt

@Configuration
class SwaggerConfiguration {

    @Bean
    fun globalHeaders(): OpenApiCustomiser = OpenApiCustomiser { openApi ->
        openApi.paths.flatMap { it.value.readOperations() }
            .forEach {
                it.addParametersItem(HeaderParameter().name("Header1").required(true))
                it.addParametersItem(HeaderParameter().name("Header2").required(true))
            }
    }
}

Expected behavior

• When I refresh the browser, it works properly without any duplicated headers.

Screenshots

After running Spring Boot application

Refresh browser once

Refresh browser twice

Additional context

• Disabling the cache through the properties below does not cause duplicate headers.

springdoc.cache.disabled= true

• I wonder if this is intended or if the configuration is wrong.

• When I debug the code, it seems that AbstractOpenApiResource 's OpenApiCustomizer logic is related. If it's a bug, I want to send a PR after fixing it.

[bnasslahsen]

@doljae,

There is no intention of such a behavior.
Please feel free to propose a PR.

[doljae]

@bnasslahsen ,
You already fixed it, I hope to make contribution 😭
Anyway, thanks for the quick fix.

[bnasslahsen]

@doljae,

I have just reverted some old code. But if you had in mind a simpler PR, you still can propose it!

[doljae]

@bnasslahsen ,
I made PR with tiny adjustment. If you don't mind, please check 🙂