This is an experimental implementation of Hypertext Transfer Protocol version 2.0.
We started to implement HTTP-draft-09/2.0 (http://tools.ietf.org/html/draft-ietf-httpbis-http2-09) and the header compression (http://tools.ietf.org/html/draft-ietf-httpbis-header-compression-05).
The nghttp2 code base was forked from spdylay project.
| Features | HTTP-draft-09/2.0 |
|---|---|
| :authority | Done |
| HPACK-draft-05 | Done |
| SETTINGS_HEADER_TABLE_SIZE | Done |
| SETTINGS_ENABLE_PUSH | Done |
| FRAME_SIZE_ERROR | Done |
| SETTINGS with ACK | Done |
| Header Continuation | |
| ALPN | Done |
The following endpoints are available to try out nghttp2
implementation. These endpoints supports HTTP-draft-09/2.0 and
the earlier draft versions are not supporeted.
https://106.186.112.116 (TLS + NPN)
NPN offers
HTTP-draft-09/2.0,spdy/3.1,spdy/3,spdy/2andhttp/1.1.Note: certificate is self-signed and a browser will show alert
http://106.186.112.116 (Upgrade + Direct)
The following packages are needed to build the library:
- pkg-config >= 0.20
- zlib >= 1.2.3
To build and run the unit test programs, the following packages are required:
- cunit >= 2.1
To build the documentation, you need to install:
- sphinx (http://sphinx-doc.org/)
To build and run the application programs (nghttp, nghttpd and
nghttpx) in src directory, the following packages are
required:
- OpenSSL >= 1.0.1
- libevent-openssl >= 2.0.8
ALPN support requires unreleased version OpenSSL >= 1.0.2.
To enable SPDY protocol in the application program nghttpx, the
following packages are required:
- spdylay >= 1.2.3
To enable -a option (getting linked assets from the downloaded
resource) in nghttp, the following packages are needed:
- libxml2 >= 2.7.7
The header compression test tools in hdtest directory require the following package:
- jansson >= 2.4
If you are using Ubuntu 12.04, you need the following packages installed:
- autoconf
- automake
- autotools-dev
- libtool
- pkg-config
- zlib1g-dev
- libcunit1-dev
- libssl-dev
- libxml2-dev
- libevent-dev
- libjansson-dev
spdylay is not packaged in Ubuntu, so you need to build it yourself: http://tatsuhiro-t.github.io/spdylay/
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/ALPN TLS extension.
It has verbose output mode for framing information. Here is sample
output from nghttp client:
$ src/nghttp -vn https://localhost:8443
[ 0.003] NPN select next protocol: the remote server offers:
* HTTP-draft-09/2.0
* spdy/3
* spdy/2
* http/1.1
NPN selected the protocol: HTTP-draft-09/2.0
[ 0.005] send SETTINGS frame <length=16, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(4):100]
[SETTINGS_INITIAL_WINDOW_SIZE(7):65535]
[ 0.006] send HEADERS frame <length=47, flags=0x05, stream_id=1>
; END_STREAM | END_HEADERS
; Open new stream
:authority: localhost:8443
:method: GET
:path: /
:scheme: https
accept: */*
accept-encoding: gzip, deflate
user-agent: nghttp2/0.1.0-DEV
[ 0.006] recv SETTINGS frame <length=16, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(4):100]
[SETTINGS_INITIAL_WINDOW_SIZE(7):65535]
[ 0.006] send SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[ 0.006] recv WINDOW_UPDATE frame <length=4, flags=0x00, stream_id=0>
(window_size_increment=1000000007)
[ 0.006] recv SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[ 0.006] recv HEADERS frame <length=132, flags=0x04, stream_id=1>
; END_HEADERS
; First response header
:status: 200
accept-ranges: bytes
content-encoding: gzip
content-length: 146
content-type: text/html
date: Sun, 27 Oct 2013 14:23:54 GMT
etag: "b1-4e5535a027780-gzip"
last-modified: Sun, 01 Sep 2013 14:34:22 GMT
server: Apache/2.4.6 (Debian)
vary: Accept-Encoding
via: 1.1 nghttpx
[ 0.006] recv DATA frame <length=146, flags=0x00, stream_id=1>
[ 0.006] recv DATA frame <length=0, flags=0x01, stream_id=1>
; END_STREAM
[ 0.007] send GOAWAY frame <length=8, flags=0x00, stream_id=0>
(last_stream_id=0, error_code=NO_ERROR(0), opaque_data(0)=[])
The HTTP Upgrade is performed like this:
$ src/nghttp -vnu http://localhost:8080
[ 0.000] HTTP Upgrade request
GET / HTTP/1.1
Host: localhost:8080
Connection: Upgrade, HTTP2-Settings
Upgrade: HTTP-draft-09/2.0
HTTP2-Settings: AAAABAAAAGQAAAAHAAD__w
Accept: */*
User-Agent: nghttp2/0.1.0-DEV
[ 0.000] HTTP Upgrade response
HTTP/1.1 101 Switching Protocols
Connection: Upgrade
Upgrade: HTTP-draft-09/2.0
[ 0.001] HTTP Upgrade success
[ 0.001] send SETTINGS frame <length=16, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(4):100]
[SETTINGS_INITIAL_WINDOW_SIZE(7):65535]
[ 0.001] recv SETTINGS frame <length=16, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(4):100]
[SETTINGS_INITIAL_WINDOW_SIZE(7):65535]
[ 0.001] recv WINDOW_UPDATE frame <length=4, flags=0x00, stream_id=0>
(window_size_increment=1000000007)
[ 0.001] recv HEADERS frame <length=121, flags=0x04, stream_id=1>
; END_HEADERS
; First response header
:status: 200
accept-ranges: bytes
content-length: 177
content-type: text/html
date: Sun, 27 Oct 2013 14:26:04 GMT
etag: "b1-4e5535a027780"
last-modified: Sun, 01 Sep 2013 14:34:22 GMT
server: Apache/2.4.6 (Debian)
vary: Accept-Encoding
via: 1.1 nghttpx
[ 0.001] recv DATA frame <length=177, flags=0x00, stream_id=1>
[ 0.001] recv DATA frame <length=0, flags=0x01, stream_id=1>
; END_STREAM
[ 0.001] send SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[ 0.001] send GOAWAY frame <length=8, flags=0x00, stream_id=0>
(last_stream_id=0, error_code=NO_ERROR(0), opaque_data(0)=[])
[ 0.001] recv SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
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/ALPN or direct
HTTP/2.0 connection. No HTTP Upgrade is supported.
-p option allows users to configure server push.
Just like nghttp, it has verbose output mode for framing
information. Here is sample output from nghttpd server:
$ src/nghttpd --no-tls -v 8080
IPv4: listen on port 8080
IPv6: listen on port 8080
[id=1] [ 1.189] send SETTINGS frame <length=8, flags=0x00, stream_id=0>
(niv=1)
[SETTINGS_MAX_CONCURRENT_STREAMS(4):100]
[id=1] [ 1.191] recv SETTINGS frame <length=16, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(4):100]
[SETTINGS_INITIAL_WINDOW_SIZE(7):65535]
[id=1] [ 1.191] recv HEADERS frame <length=47, flags=0x05, stream_id=1>
; END_STREAM | END_HEADERS
; Open new stream
:authority: localhost:8080
:method: GET
:path: /
:scheme: http
accept: */*
accept-encoding: gzip, deflate
user-agent: nghttp2/0.1.0-DEV
[id=1] [ 1.192] send SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[id=1] [ 1.192] send HEADERS frame <length=70, flags=0x04, stream_id=1>
; END_HEADERS
; First response header
:status: 404
content-encoding: gzip
content-type: text/html; charset=UTF-8
date: Sun, 27 Oct 2013 14:27:53 GMT
server: nghttpd nghttp2/0.1.0-DEV
[id=1] [ 1.192] send DATA frame <length=117, flags=0x00, stream_id=1>
[id=1] [ 1.192] send DATA frame <length=0, flags=0x01, stream_id=1>
; END_STREAM
[id=1] [ 1.192] stream_id=1 closed
[id=1] [ 1.192] recv SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[id=1] [ 1.192] recv GOAWAY frame <length=8, flags=0x00, stream_id=0>
(last_stream_id=0, error_code=NO_ERROR(0), opaque_data(0)=[])
[id=1] [ 1.192] closed
The nghttpx is a multi-threaded reverse proxy for
HTTP-draft-09/2.0, 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 |
--http2-proxy |
HTTP/2.0, SPDY, HTTP/1.1 (TLS) | HTTP/1.1 | SPDY proxy |
--http2-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-09/2.0, SPDY and HTTP/1.1 and can be deployed SSL/TLS terminator for existing web server.
The default mode, --http2-proxy and --http2-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 --http2-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 does not support server push.
In the default mode, (without any of --http2-proxy,
--http2-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 --http2-proxy 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 --http2-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
--http2-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)
The hdtest directory contains header compression test tools. The
deflatehd is command-line header compression tool. The
inflatehd is command-line header decompression tool. Both tools
read input from stdin and write output to stdout. The errors are
written to stderr. They take JSON as input and output.
The deflatehd reads JSON array or HTTP/1-style header fields from
stdin and outputs compressed header block in JSON array.
For the JSON input, the element of input array must be a JSON object. Each object must have at least following key:
- headers
- A JSON array of name/value pairs. The each element is a JSON array of 2 strings. The index 0 must contain header name and the index 1 must contain header value.
Example:
[
{
"headers": [
[ ":method", "GET" ],
[ ":path", "/" ]
]
},
{
"headers": [
[ ":method", "POST" ],
[ ":path", "/" ]
]
}
]
These header sets are processed in the order they appear in the JSON outer most array using same compression context.
With -t option, the program can accept more familiar HTTP/1 style
header field block. Each header set is delimited by empty line:
Example:
:method: GET :scheme: https :path: / :method: POST user-agent: nghttp2
The output is a JSON array and each element is JSON object, which has at least following keys:
- seq
- The index of header set in the input.
- inputLen
- The sum of length of name/value pair in the input.
- outputLength
- The length of compressed header block.
- percentageOfOriginalSize
- inputLen / outputLength * 100
- output
- The compressed header block in hex string.
Examples:
[
{
"seq": 0,
"inputLen": 66,
"outputLength": 20,
"percentageOfOriginalSize": 30.303030303030305,
"output": "818703881f3468e5891afcbf863c856659c62e3f"
},
{
"seq": 1,
"inputLen": 74,
"outputLength": 10,
"percentageOfOriginalSize": 13.513513513513514,
"output": "87038504252dd5918386"
}
]
The output can be used as the input for inflatehd.
With -d option, the extra headerTable key is added and its
associated value contains the state of dyanmic header table after the
corresponding header set was processed. The value contains following
keys:
- entries
- The entry in the header table. If
referencedistrue, it is in the reference set. Thesizeincludes the overhead (32 bytes). Theindexcorresponds to the index of header table. Thenameis the header field name and thevalueis the header field value. They may be displayed as**DEALLOCATED**, which means that the memory for that string is freed and not available. This will happen when the specifying smaller value in-Sthan-s. - size
- The sum of the spaces entries occupied, this includes the entry overhead.
- maxSize
- The maximum header table size.
- deflateSize
- The sum of the spaces entries occupied within
maxDeflateSize. - maxDeflateSize
- The maximum header table size encoder uses. This can be smaller
than
maxSize. In this case, encoder only uses up to firstmaxDeflateSizebuffer. Since the header table size is stillmaxSize, the encoder has to keep track of entries ouside themaxDeflateSizebut inside themaxSizeand make sure that they are no longer referenced.
Example:
[
{
"seq": 0,
"inputLen": 66,
"outputLength": 20,
"percentageOfOriginalSize": 30.303030303030305,
"output": "818703881f3468e5891afcbf863c856659c62e3f",
"headerTable": {
"entries": [
{
"index": 0,
"name": "user-agent",
"value": "nghttp2",
"referenced": true,
"size": 49
},
{
"index": 1,
"name": ":path",
"value": "/",
"referenced": true,
"size": 38
},
{
"index": 2,
"name": ":authority",
"value": "example.org",
"referenced": true,
"size": 53
},
{
"index": 3,
"name": ":scheme",
"value": "https",
"referenced": true,
"size": 44
},
{
"index": 4,
"name": ":method",
"value": "GET",
"referenced": true,
"size": 42
}
],
"size": 226,
"maxSize": 4096,
"deflateSize": 226,
"maxDeflateSize": 4096
}
},
{
"seq": 1,
"inputLen": 74,
"outputLength": 10,
"percentageOfOriginalSize": 13.513513513513514,
"output": "87038504252dd5918386",
"headerTable": {
"entries": [
{
"index": 0,
"name": ":path",
"value": "/account",
"referenced": true,
"size": 45
},
{
"index": 1,
"name": ":method",
"value": "POST",
"referenced": true,
"size": 43
},
{
"index": 2,
"name": "user-agent",
"value": "nghttp2",
"referenced": true,
"size": 49
},
{
"index": 3,
"name": ":path",
"value": "/",
"referenced": false,
"size": 38
},
{
"index": 4,
"name": ":authority",
"value": "example.org",
"referenced": true,
"size": 53
},
{
"index": 5,
"name": ":scheme",
"value": "https",
"referenced": true,
"size": 44
},
{
"index": 6,
"name": ":method",
"value": "GET",
"referenced": false,
"size": 42
}
],
"size": 314,
"maxSize": 4096,
"deflateSize": 314,
"maxDeflateSize": 4096
}
}
]
The inflatehd reads JSON array from stdin and outputs decompressed
name/value pairs in JSON array. The element of input array must be a
JSON object. Each object must have at least following key:
- output
- compressed header block in hex string.
Example:
[
{ "output": "0284f77778ff" },
{ "output": "0185fafd3c3c7f81" }
]
The output is a JSON array and each element is JSON object, which has at least following keys:
- seq
- The index of header set in the input.
- headers
- The JSON array contains decompressed name/value pairs. Each element is JSON aray having 2 elements. The index 0 of the array contains the header field name. The index 1 contains the header field value.
Example:
[
{
"seq": 0,
"headers": [
[":authority", "example.org"],
[":method", "GET"],
[":path", "/"],
[":scheme", "https"],
["user-agent", "nghttp2"]
]
},
{
"seq": 1,
"headers": [
[":authority", "example.org"],
[":method", "POST"],
[":path", "/account"],
[":scheme", "https"],
["user-agent", "nghttp2"]
]
}
]
The output can be used as the input for deflatehd.
With -d option, the extra headerTable key is added and its
associated value contains the state of dyanmic header table after the
corresponding header set was processed. The format is the same as
deflatehd.