This is an experimental implementation of Hypertext Transfer Protocol version 2.0.
We started to implement HTTP-defat-04/2.0 (http://tools.ietf.org/html/draft-ietf-httpbis-http2-04) based on spdylay code base. The header compression is based on http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-01
Currently, the library lacks the following features:
The following packages are needed to build the library:
To build and run the unit test programs, the following packages are required:
To build and run the application programs (nghttp, nghttpd and nghttpx) in src directory, the following packages are required:
To enable SPDY protocol in the application program nghttpx, the following packages are required:
To enable -a option (getting linked assets from the downloaded resouce) in nghttp, the following packages are needed:
If you are using Ubuntu 12.04, you need the following packages installed:
spdylay is not packaged in Ubuntu, so you need to build it yourself: http://spdylay.sourceforge.net/
Building from git is easy, but please be sure that at least autoconf 2.68 is used:
$ autoreconf -i
$ automake
$ autoconf
$ ./configure
$ make
Note
Documentation is still incomplete.
To build documentation, run:
$ make html
The documents will be generated under doc/manual/html/.
The generated documents will not be installed with make install.
The online documentation is available at http://tatsuhiro-t.github.io/nghttp2/
The src directory contains HTTP/2.0 client, server and proxy programs.
nghttp is a HTTP/2.0 client. It can connect to the HTTP/2.0 server with prior knowledge, HTTP Upgrade and NPN TLS extension.
By default, it uses SSL/TLS connection. Use --no-tls option to disable it.
It has verbose output mode for framing information. Here is sample output from nghttp client:
$ src/nghttp -nv https://localhost:3000/
[ 0.000] NPN select next protocol: the remote server offers:
* HTTP-draft-04/2.0
* spdy/3
* spdy/2
* http/1.1
NPN selected the protocol: HTTP-draft-04/2.0
[ 0.005] send SETTINGS frame <length=0, flags=0, stream_id=0>
(niv=0)
[ 0.005] send HEADERS frame <length=58, flags=5, stream_id=1>
; END_STREAM | END_HEADERS
; Open new stream
:host: localhost:3000
:method: GET
:path: /
:scheme: https
accept: */*
accept-encoding: gzip, deflate
user-agent: nghttp2/0.1.0-DEV
[ 0.005] recv SETTINGS frame <length=16, flags=0, stream_id=0>
(niv=2)
[4:100]
[7:65536]
[ 0.005] recv WINDOW_UPDATE frame <length=4, flags=1, stream_id=0>
; END_FLOW_CONTROL
(window_size_increment=0)
[ 0.006] recv HEADERS frame <length=179, flags=4, stream_id=1>
; END_HEADERS
; First response header
:status: 200 OK
accept-ranges: bytes
content-encoding: gzip
content-length: 56
content-type: text/html
date: Sat, 27 Jul 2013 12:08:56 GMT
etag: "cf405c-2d-45adabdf282c0"
last-modified: Tue, 04 Nov 2008 10:44:03 GMT
server: Apache/2.2.22 (Debian)
vary: Accept-Encoding
via: 1.1 nghttpx
[ 0.006] recv DATA frame (length=56, flags=0, stream_id=1)
[ 0.006] recv DATA frame (length=0, flags=1, stream_id=1)
[ 0.006] send GOAWAY frame <length=8, flags=0, stream_id=0>
(last_stream_id=0, error_code=NO_ERROR(0), opaque_data=)
The HTTP Upgrade is performed like this:
$ src/nghttp --no-tls -nvu http://localhost:3000/
[ 0.000] HTTP Upgrade request
GET / HTTP/1.1
Host: localhost:3000
Connection: Upgrade, HTTP2-Settings
Upgrade: HTTP-draft-04/2.0
HTTP2-Settings: AAAABAAAAGQAAAAHAAD__w
Accept: */*
User-Agent: nghttp2/0.1.0-DEV
[ 0.183] HTTP Upgrade response
HTTP/1.1 101 Switching Protocols
Connection: Upgrade
Upgrade: HTTP/2.0
[ 0.183] HTTP Upgrade success
[ 0.183] send SETTINGS frame <length=16, flags=0x00, stream_id=0>
(niv=2)
[4:100]
[7:65535]
[ 0.202] recv SETTINGS frame <length=16, flags=0x00, stream_id=0>
(niv=2)
[4:100]
[7:65536]
[ 0.202] recv WINDOW_UPDATE frame <length=4, flags=0x01, stream_id=0>
; END_FLOW_CONTROL
(window_size_increment=0)
[ 0.275] recv HEADERS frame <length=198, flags=0x04, stream_id=1>
; END_HEADERS
; First response header
:status: 200 OK
accept-ranges: bytes
content-length: 45
content-type: text/html
date: Sat, 03 Aug 2013 10:21:20 GMT
etag: "cf405c-2d-45adabdf282c0"
last-modified: Tue, 04 Nov 2008 10:44:03 GMT
server: Apache/2.2.22 (Debian)
vary: Accept-Encoding
via: 1.1 nghttpx
x-pad: avoid browser bug
[ 0.275] recv DATA frame (length=45, flags=0, stream_id=1)
[ 0.275] recv DATA frame (length=0, flags=1, stream_id=1)
[ 0.275] send GOAWAY frame <length=8, flags=0x00, stream_id=0>
(last_stream_id=0, error_code=NO_ERROR(0), opaque_data=)
nghttpd is static web server. It is single threaded and multiplexes connections using non-blocking socket.
By default, it uses SSL/TLS connection. Use --no-tls option to disable it.
nghttpd only accept the HTTP/2.0 connection via NPN or direct HTTP/2.0 connection. No HTTP Upgrade is supported.
Just like nghttp, it has verbose output mode for framing information. Here is sample output from nghttpd server:
$ src/nghttpd 3000 --no-tls -v
IPv4: listen on port 3000
IPv6: listen on port 3000
[id=1] [ 1.020] send SETTINGS frame <length=8, flags=0, stream_id=0>
(niv=1)
[4:100]
[id=1] [ 1.020] closed
[id=2] [ 1.838] send SETTINGS frame <length=8, flags=0, stream_id=0>
(niv=1)
[4:100]
[id=2] [ 1.838] recv SETTINGS frame <length=0, flags=0, stream_id=0>
(niv=0)
[id=2] [ 1.838] recv HEADERS frame <length=58, flags=5, stream_id=1>
; END_STREAM | END_HEADERS
; Open new stream
:host: localhost:3000
:method: GET
:path: /
:scheme: http
accept: */*
accept-encoding: gzip, deflate
user-agent: nghttp2/0.1.0-DEV
[id=2] [ 1.838] send HEADERS frame <length=105, flags=4, stream_id=1>
; END_HEADERS
; First response header
:status: 404 Not Found
content-encoding: gzip
content-type: text/html; charset=UTF-8
date: Sat, 27 Jul 2013 12:32:10 GMT
server: nghttpd nghttp2/0.1.0-DEV
[id=2] [ 1.838] send DATA frame (length=127, flags=0, stream_id=1)
[id=2] [ 1.838] send DATA frame (length=0, flags=1, stream_id=1)
[id=2] [ 1.838] stream_id=1 closed
[id=2] [ 1.839] closed
The nghttpx is a multi-threaded reverse proxy for HTTP-draft-04/2.0, SPDY and HTTP/1.1. It has several operation modes:
| Mode option | Frontend | Backend | Note |
|---|---|---|---|
| default mode | HTTP/2.0, SPDY, HTTP/1.1 (TLS) | HTTP/1.1 | Reverse proxy |
| --spdy | HTTP/2.0, SPDY, HTTP/1.1 (TLS) | HTTP/1.1 | SPDY proxy |
| --spdy-bridge | HTTP/2.0, SPDY, HTTP/1.1 (TLS) | HTTP/2.0 (TLS) | |
| --client | HTTP/2.0, HTTP/1.1 | HTTP/2.0 (TLS) | |
| --client-proxy | HTTP/2.0, HTTP/1.1 | HTTP/2.0 (TLS) | Forward proxy |
The interesting mode at the moment is the default mode. It works like a reverse proxy and listens HTTP-draft-04/2.0, SPDY and HTTP/1.1 and can be deployed SSL/TLS terminator for existing web server.
The default mode, --spdy and --spdy-bridge modes use SSL/TLS in the frontend connection by default. To disable SSL/TLS, use --frontend-no-tls option. If that option is used, SPDY is disabled in the frontend and incoming HTTP/1.1 connection can be upgraded to HTTP/2.0 through HTTP Upgrade.
The --spdy-bridge, --client and --client-proxy modes use SSL/TLS in the backend connection by deafult. To disable SSL/TLS, use --backend-no-tls option.
The nghttpx supports configuration file. See --conf option and sample configuration file nghttpx.conf.sample.
The nghttpx is ported from shrpx in spdylay project, and it still has SPDY color in option names. They will be fixed as the development goes.
In the default mode, (without any of --spdy, --spdy-bridge, --client-proxy and --client options), nghttpx works as reverse proxy to the backend server:
Client <-- (HTTP/2.0, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/1.1) --> Web Server
[reverse proxy]
With --spdy option, it works as so called secure proxy (aka SPDY proxy):
Client <-- (HTTP/2.0, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/1.1) --> Proxy
[secure proxy] (e.g., Squid)
The Client in the above is needs to be configured to use nghttpx as secure proxy.
At the time of this writing, Chrome is the only browser which supports secure proxy. The one way to configure Chrome to use secure proxy is create proxy.pac script like this:
function FindProxyForURL(url, host) {
return "HTTPS SERVERADDR:PORT";
}
SERVERADDR and PORT is the hostname/address and port of the machine nghttpx is running. Please note that Chrome requires valid certificate for secure proxy.
Then run chrome with the following arguments:
$ google-chrome --proxy-pac-url=file:///path/to/proxy.pac --use-npn
With --spdy-bridge, it accepts HTTP/2.0, SPDY and HTTP/1.1 connections and communicates with backend in HTTP/2.0:
Client <-- (HTTP/2.0, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/2.0) --> Web or HTTP/2.0 Proxy etc
(e.g., nghttpx -s)
With --client-proxy option, it works as forward proxy and expects that the backend is HTTP/2.0 proxy:
Client <-- (HTTP/2.0, HTTP/1.1) --> nghttpx <-- (HTTP/2.0) --> HTTP/2.0 Proxy
[forward proxy] (e.g., nghttpx -s)
The Client is needs to be configured to use nghttpx as forward proxy. The frontend HTTP/1.1 connection can be upgraded to HTTP/2.0 through HTTP Upgrade. With the above configuration, one can use HTTP/1.1 client to access and test their HTTP/2.0 servers.
With --client option, it works as reverse proxy and expects that the backend is HTTP/2.0 Web server:
Client <-- (HTTP/2.0, HTTP/1.1) --> nghttpx <-- (HTTP/2.0) --> Web Server
[reverse proxy]
The frontend HTTP/1.1 connection can be upgraded to HTTP/2.0 through HTTP Upgrade.
For the operation modes which talk to the backend in HTTP/2.0 over SSL/TLS, the backend connections can be tunneled though HTTP proxy. The proxy is specified using --backend-http-proxy-uri option. The following figure illustrates the example of --spdy-bridge and --backend-http-proxy-uri option to talk to the outside HTTP/2.0 proxy through HTTP proxy:
Client <-- (HTTP/2.0, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/2.0) --
--===================---> HTTP/2.0 Proxy
(HTTP proxy tunnel) (e.g., nghttpx -s)