# Support for POST client body sent with Transfer-Encoding: chunked **URL:** \ **Category:** NGINX\ **Created:** [February 3, 2008, 10:47pm UTC](https://www.ruby-forum.com/t/support-for-post-client-body-sent-with-transfer-encoding-chunked/127989 "2008-02-03T22:47:50Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![carlos](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecae2f/32.png) [@carlos](https://www.ruby-forum.com/u/carlos)\ **Post date:** [February 3, 2008, 10:47pm UTC](https://www.ruby-forum.com/t/support-for-post-client-body-sent-with-transfer-encoding-chunked/127989/1 "2008-02-03T22:47:50Z")
In the process of switching from Apache 2 to an all-nginx setup for front-end servers I have found a nginx (miss-)feature that makes it impossible to service certain clients. Basically nginx will refuse to serve POST requests that don’t specify a Content-Length parameter and use Transfer-Encoding: chunked for the POST client body. A 411 error will be served every time such a request is received. Setting up nginx as a proxy doesn’t work either, the same 411 error is served. It appears nginx is buffering the POST body and applies the same limiting rules even for proxy\_pass-ed requests. I’ve looked in the code and it appears to be an explicit limitation (ngx\_http\_process\_request\_header() function in ngx\_http\_request.c), and the changelog mentions it as an actual “bugfix” (nginx 0.3.12). I’m not an expert in technolegalese but it appears that TE:chunked POST bodies is a HTTP 1.1 feature and there are actual products sending such POST bodies, and I am pretty sure other servers that Apache 2 support it too. Is there any technical explanation for nginx not supporting, or at least explicitly disabling it? Anybody knows a work-around for it? I guess the correct answer is “add the feature and send a patch”, but asking first to not reinvent any wheel won’t hurt 🙂 (The clients in question are J2ME phones. I can do my own HTTP client for the few of them that expose TCP sockets to applications, but the majority only allow high-level “HTTP connections” that don’t expose any socket internals or details about how the actual request is formatted. Not all of them are doing TE:chunked POST but the ones that do are very significant, for example the official Sun J2ME emulator.) ---
**Author:** ![carlos](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecae2f/32.png) [@carlos](https://www.ruby-forum.com/u/carlos)\ **Post date:** [February 15, 2008, 7:26pm UTC](https://www.ruby-forum.com/t/support-for-post-client-body-sent-with-transfer-encoding-chunked/127989/2 "2008-02-15T19:26:50Z")
Carlos, Did you find a work around for this issue? I’m having the same issue as well I believed. We have a system that uses a browser, java client, and a CAD client. The first two can upload files fine except the last one. ---
**Author:** ![carlos](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecae2f/32.png) [@carlos](https://www.ruby-forum.com/u/carlos)\ **Post date:** [February 15, 2008, 8:02pm UTC](https://www.ruby-forum.com/t/support-for-post-client-body-sent-with-transfer-encoding-chunked/127989/3 "2008-02-15T20:02:49Z")
Hello Tho, Unfortunately I didn’t find a work around. I just went and set up a dedicated Apache in a high port to serve the mobile clients (a solution that has its own problems since it is common for mobile carriers to block non-standard ports.) If you are dealing with a desktop client app you may have some control over its configuration. The problem comes mainly from HTTP 1.1 clients assuming the server has full support for HTTP 1.1 features, like chunked POST bodies. Try to force HTTP 1.0 in the client, that should disable chunked POST. I actually spent some time with the source of nginx. I was impressed with the extremely optimized approach to everything, from I/O to buffering to even string comparisons. It was also very tidy and readable. Disabling the 411 error check was easy enough but the buffering code for the POST body is written under the asumption that its length is fully known in advance (i.e. from the Content-Length header sent by the client.) Apparently it is legal for HTTP 1.1 clients to not send a Content-Length header and just rely on the auto-finalizing feature of the chunked encoding (sending a 0 length chunk.) The buffering code was not ready for this at all and would have required extensive modifications. Having 0 experience with the code it would take me way too long to come up with a working patch, so I decided to just go back to Apache for the time being. ---
**Author:** ![carlos](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/ecae2f/32.png) [@carlos](https://www.ruby-forum.com/u/carlos)\ **Post date:** [November 17, 2008, 11:08am UTC](https://www.ruby-forum.com/t/support-for-post-client-body-sent-with-transfer-encoding-chunked/127989/4 "2008-11-17T11:08:35Z")
Hello, guys. I’m having the same issue with nginx-0.7.21 - “on any POST with Transfer-Encoding: chunked, I do receive: HTTP/1.1 411 Length Required”. It’s not RFC complaint. [http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.4](http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.4) {{{ If a message is received with both a Transfer-Encoding header field and a Content-Length header field, the latter MUST be ignored. }}} Maybe Igor will shed a light on the issue and tell us if there is a plans for such feature in nginx.