we need to add a test to the core server TCK. Similar to micronaut-projects/micronaut-core#9791

@driverpt Do you want to contribute that PR to core?

Hello,

After some digging and Testing with AWS API Gateway Payload V2, I have discovered that If a header value contains a comma, it's appended "as is".

i.e.:

X-SomeHeader: Foo,Bar
X-SomeHeader: Baz

We will have something like:

A comma is widely used in most User-Agent Strings. Example: Safari: Mozilla/5.0 (Macintosh; Intel Mac OS X 13_5_1) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.5 Safari/605.1.15, which was causing the PR I've created to break TCK Tests.

What is possibly needed is a Property that would tell the Request Converter not to split by comma in certain headers.

WDYT @sdelamo @graemerocher @timyates ?

@msailes , can you also provide some insights on this?

I just check this with Micronaut Framework 4.2.0

Sending a request such as:

GET /headers HTTP/1.1
ETag: A
ETag: B
Host: pr76sk5f71.execute-api.us-east-1.amazonaws.com
Connection: close
User-Agent: RapidAPI/4.2.0 (Macintosh; OS X/13.6.1) GCDHTTPRequest

with a controller:

package temp1;

import io.micronaut.http.HttpHeaders;
import io.micronaut.http.HttpRequest;
import io.micronaut.http.annotation.Controller;
import io.micronaut.http.annotation.Get;

import java.util.Collections;
import java.util.List;
import java.util.Map;

@Controller("/headers")
public class HeadersController {

    @Get
    Map<String, List<String>> receiveMultipleHeaders(HttpRequest<?> request) {
        return Collections.singletonMap("etag" , request.getHeaders().getAll(HttpHeaders.ETAG));
    }
}

we get response:

HTTP/1.1 200 OK
Date: Fri, 24 Nov 2023 12:17:38 GMT
Content-Type: application/json
Content-Length: 16
Connection: close
Apigw-Requestid: O5wfYhZroAMEJlg=

{"etag":["A,B"]}

I am going to close this issue for now. @driverpt let me know if you think we should do any changes about this.