Before Dan's presentation, I hadn't heard of 100 (Continue), but then I ran into it today. A client had an issue with a .NET client talking to a Jetty instance, and the conversation went something like this:
POST /uri/foo HTTP/1.1 [...] Expect: 100-continue Connection: Close 100 Continue [Jetty closes the connection.]
It turns out that this is an issue with the way that Jetty handles the Connection: Close header. Even though it seems reasonable to drop the connection according to 14.10 (if you think of the 100 Continue as a response), dropping the connection violates 8.2.3:
Upon receiving a request which includes an Expect request-header field with the "100-continue" expectation, an origin server MUST either respond with 100 (Continue) status and continue to read from the input stream, or respond with a final status code.
Experiences like this are the reason that I always smile when someone tells me that they've built their own HTTP client or server implementation; it's not that simple.
Add a comment.
