RFR: 8314978: Multiple server call from connection failing with expect100 in getOutputStream [v2]

[Vyom Tewari]

On Fri, 8 Sep 2023 11:32:26 GMT, Daniel Fuchs <dfuchs at openjdk.org> wrote:

> If another code than 100 is returned there's no point in sending the request body, hence the exception. You can get the 200 and the response at this point by looking at the status code and reading the response input stream. IMHO it's better than returning null or some other special output stream that would discard the data (or throw when it's used). It's typically what you'd expect if 417 was returned, but 200 falls down in the same category too. So catch the exception and check the status.


As per specification (https://www.rfc-editor.org/rfc/rfc9110#section-10.1.1-11.4) if server returns non 100 code then one of the client side requirement is as follows.

A client that receives a 417 (Expectation Failed) status code in response to a request containing a 100-continue expectation SHOULD repeat that request without a 100-continue expectation, since the 417 response merely indicates that the response chain does not support expectations (e.g., it passes through an HTTP/1.0 server).  

I checked with JDK new HttpClient and it don’t throw exception. Please find the below code that works well with my test server.

###################################
String requestBody = "This is payload that i am sending it to test.";

        HttpClient client = HttpClient.newHttpClient();
        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create("http://localhost:9000"))
                .POST(HttpRequest.BodyPublishers.ofString(requestBody))
                .expectContinue(true)
                .build();

        HttpResponse<String> response = client.send(request,
                HttpResponse.BodyHandlers.ofString());

        System.out.println(response.statusCode() + ", " + response.body());
        HttpHeaders headers = response.headers();
        System.out.println(headers.firstValue("field1"));
####################################

-------------

PR Comment: https://git.openjdk.org/jdk/pull/15483#issuecomment-1715501101