nghttp2 - HTTP/2 C Library ========================== This is an implementation of the Hypertext Transfer Protocol version 2 in C. The framing layer of HTTP/2 is implemented as a reusable C library. On top of that, we have implemented an HTTP/2 client, server and proxy. We have also developed load test and benchmarking tools for HTTP/2 and SPDY. An HPACK encoder and decoder are available as a public API. An experimental high level C++ library is also available. We have Python bindings of this libary, but we do not have full code coverage yet. Development Status ------------------ We have implemented `RFC 7540 `_ HTTP/2 and `RFC 7541 `_ HPACK - Header Compression for HTTP/2 The nghttp2 code base was forked from the spdylay (https://github.com/tatsuhiro-t/spdylay) project. Public Test Server ------------------ The following endpoints are available to try out our nghttp2 implementation. * https://nghttp2.org/ (TLS + ALPN/NPN) This endpoint supports ``h2``, ``h2-16``, ``h2-14``, ``spdy/3.1`` and ``http/1.1`` via ALPN/NPN and requires TLSv1.2 for HTTP/2 connection. * http://nghttp2.org/ (HTTP Upgrade and HTTP/2 Direct) ``h2c`` and ``http/1.1``. Requirements ------------ The following package is required to build the libnghttp2 library: * pkg-config >= 0.20 To build and run the unit test programs, the following package is 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 the ``src`` directory, the following packages are required: * OpenSSL >= 1.0.1 * libev >= 4.15 * zlib >= 1.2.3 ALPN support requires OpenSSL >= 1.0.2 (released 22 January 2015). To enable the SPDY protocol in the application program ``nghttpx`` and ``h2load``, the following package is required: * spdylay >= 1.3.0 To enable ``-a`` option (getting linked assets from the downloaded resource) in ``nghttp``, the following package is required: * libxml2 >= 2.7.7 The HPACK tools require the following package: * jansson >= 2.5 To build sources under the examples directory, libevent is required: * libevent-openssl >= 2.0.8 To mitigate heap fragmentation in long running server programs (``nghttpd`` and ``nghttpx``), jemalloc is recommended: * jemalloc libnghttp2_asio C++ library requires the following packages: * libboost-dev >= 1.54.0 * libboost-thread-dev >= 1.54.0 The Python bindings require the following packages: * cython >= 0.19 * python >= 2.7 If you are using Ubuntu 14.04 LTS (trusty), run the following to install the needed packages:: sudo apt-get install make binutils autoconf automake autotools-dev libtool pkg-config \ zlib1g-dev libcunit1-dev libssl-dev libxml2-dev libev-dev libevent-dev libjansson-dev \ libjemalloc-dev cython python3.4-dev spdylay is not packaged in Ubuntu, so you need to build it yourself: http://tatsuhiro-t.github.io/spdylay/ Building from git ----------------- Building from git is easy, but please be sure that at least autoconf 2.68 is used:: $ autoreconf -i $ automake $ autoconf $ ./configure $ make To compile the source code, gcc >= 4.8.3 or clang >= 3.4 is required. .. note:: Mac OS X users may need the ``--disable-threads`` configure option to disable multi-threading in nghttpd, nghttpx and h2load to prevent them from crashing. A patch is welcome to make multi threading work on Mac OS X platform. Notes for building on Windows (Mingw/Cygwin) -------------------------------------------- Under Mingw environment, you can only compile the library, it's ``libnghttp2-X.dll`` and ``libnghttp2.a``. If you want to compile the applications(``h2load``, ``nghttp``, ``nghttpx``, ``nghttpd``), you need to use the Cygwin environment. Under Cygwin environment, to compile the applications you need to compile and install the libev first. Secondly, you need to undefine the macro ``__STRICT_ANSI__``, if you not, the functions ``fdopen``, ``fileno`` and ``strptime`` will not available. the sample command like this:: $ export CFLAGS="-U__STRICT_ANSI__ -I$libev_PREFIX/include -L$libev_PREFIX/lib" $ export CXXFLAGS=$CFLAGS $ ./configure $ make If you want to compile the applications under ``examples/``, you need to remove or rename the ``event.h`` from libev's installation, because it conflicts with libevent's installation. Building the documentation -------------------------- .. note:: Documentation is still incomplete. To build the 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 https://nghttp2.org/documentation/ Unit tests ---------- Unit tests are done by simply running `make check`. Integration tests ----------------- We have the integration tests for the nghttpx proxy server. The tests are written in the `Go programming language `_ and uses its testing framework. We depend on the following libraries: * https://github.com/bradfitz/http2 * https://github.com/tatsuhiro-t/go-nghttp2 * https://golang.org/x/net/spdy To download the above packages, after settings ``GOPATH``, run the following command under ``integration-tests`` directory:: $ make itprep To run the tests, run the following command under ``integration-tests`` directory:: $ make it Inside the tests, we use port 3009 to run the test subject server. Migration from v0.7.9 or earlier -------------------------------- nghttp2 v1.0.0 introduced several backward incompatible changes. In this section, we describe these changes and how to migrate to v1.0.0. ALPN protocol ID is now ``h2`` and ``h2c`` ++++++++++++++++++++++++++++++++++++++++++ Previously we announced ``h2-14`` and ``h2c-14``. v1.0.0 implements final protocol version, and we changed ALPN ID to ``h2`` and ``h2c``. The macros ``NGHTTP2_PROTO_VERSION_ID``, ``NGHTTP2_PROTO_VERSION_ID_LEN``, ``NGHTTP2_CLEARTEXT_PROTO_VERSION_ID``, and ``NGHTTP2_CLEARTEXT_PROTO_VERSION_ID_LEN`` have been updated to reflect this change. Basically, existing applications do not have to do anything, just recompiling is enough for this change. Use word "client magic" where we use "client connection preface" ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ We use "client connection preface" to mean first 24 bytes of client connection preface. This is technically not correct, since client connection preface is composed of 24 bytes client magic byte string followed by SETTINGS frame. For clarification, we call "client magic" for this 24 bytes byte string and updated API. * ``NGHTTP2_CLIENT_CONNECTION_PREFACE`` was replaced with ``NGHTTP2_CLIENT_MAGIC``. * ``NGHTTP2_CLIENT_CONNECTION_PREFACE_LEN`` was replaced with ``NGHTTP2_CLIENT_MAGIC_LEN``. * ``NGHTTP2_BAD_PREFACE`` was renamed as ``NGHTTP2_BAD_CLIENT_MAGIC`` The alreay deprecated ``NGHTTP2_CLIENT_CONNECTION_HEADER`` and ``NGHTTP2_CLIENT_CONNECTION_HEADER_LEN`` were removed. If application uses these macros, just replace old ones with new ones. Since v1.0.0, client magic is sent by library (see next subsection), so client application may just remove these macro use. Client magic is sent by library +++++++++++++++++++++++++++++++ Previously nghttp2 library did not send client magic, which is first 24 bytes byte string of client connection preface, and client applications have to send it by themselves. Since v1.0.0, client magic is sent by library via first call of ``nghttp2_session_send()`` or ``nghttp2_session_mem_send()``. The client applications which send client magic must remove the relevant code. Remove HTTP Alternative Services (Alt-Svc) related code +++++++++++++++++++++++++++++++++++++++++++++++++++++++ Alt-Svc specification is not finalized yet. To make our API stable, we have decided to remove all Alt-Svc related API from nghttp2. * ``NGHTTP2_EXT_ALTSVC`` was removed. * ``nghttp2_ext_altsvc`` was removed. We have already removed the functionality of Alt-Svc in v0.7 series and they have been essentially noop. The application using these macro and struct, remove those lines. Use nghttp2_error in nghttp2_on_invalid_frame_recv_callback +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Previously ``nghttp2_on_invalid_frame_recv_cb_called`` took the ``error_code``, defined in ``nghttp2_error_code``, as parameter. But they are not detailed enough to debug. Therefore, we decided to use more detailed ``nghttp2_error`` values instead. The application using this callback should update the callback signature. If it treats ``error_code`` as HTTP/2 error code, update the code so that it is treated as ``nghttp2_error``. Receive client magic by default +++++++++++++++++++++++++++++++ Previously nghttp2 did not process client magic (24 bytes byte string). To make it deal with it, we had to use ``nghttp2_option_set_recv_client_preface()``. Since v1.0.0, nghttp2 processes client magic by default and ``nghttp2_option_set_recv_client_preface()`` was removed. Some application may want to disable this behaviour, so we added ``nghttp2_option_set_no_recv_client_magic()`` to achieve this. The application using ``nghttp2_option_set_recv_client_preface()`` with nonzero value, just remove it. The application using ``nghttp2_option_set_recv_client_preface()`` with zero value or not using it must use ``nghttp2_option_set_no_recv_client_magic()`` with nonzero value. Client, Server and Proxy programs --------------------------------- The ``src`` directory contains the HTTP/2 client, server and proxy programs. nghttp - client +++++++++++++++ ``nghttp`` is a HTTP/2 client. It can connect to the HTTP/2 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:: $ nghttp -nv https://nghttp2.org [ 0.033][NPN] server offers: * h2 * spdy/3.1 * http/1.1 The negotiated protocol: h2 [ 0.068] send SETTINGS frame (niv=3) [SETTINGS_MAX_CONCURRENT_STREAMS(3):100] [SETTINGS_INITIAL_WINDOW_SIZE(4):65535] [SETTINGS_COMPRESS_DATA(5):1] [ 0.068] send HEADERS frame ; END_STREAM | END_HEADERS (padlen=0) ; Open new stream :authority: nghttp2.org :method: GET :path: / :scheme: https accept: */* accept-encoding: gzip, deflate user-agent: nghttp2/0.4.0-DEV [ 0.068] recv SETTINGS frame (niv=2) [SETTINGS_MAX_CONCURRENT_STREAMS(3):100] [SETTINGS_INITIAL_WINDOW_SIZE(4):65535] [ 0.068] send SETTINGS frame ; ACK (niv=0) [ 0.079] recv SETTINGS frame ; ACK (niv=0) [ 0.080] (stream_id=1, noind=0) :status: 200 [ 0.080] (stream_id=1, noind=0) accept-ranges: bytes [ 0.080] (stream_id=1, noind=0) age: 15 [ 0.080] (stream_id=1, noind=0) content-length: 40243 [ 0.080] (stream_id=1, noind=0) content-type: text/html [ 0.080] (stream_id=1, noind=0) date: Wed, 14 May 2014 15:14:30 GMT [ 0.080] (stream_id=1, noind=0) etag: "535d0eea-9d33" [ 0.080] (stream_id=1, noind=0) last-modified: Sun, 27 Apr 2014 14:06:34 GMT [ 0.080] (stream_id=1, noind=0) server: nginx/1.4.6 (Ubuntu) [ 0.080] (stream_id=1, noind=0) x-varnish: 2114900538 2114900537 [ 0.080] (stream_id=1, noind=0) via: 1.1 varnish, 1.1 nghttpx [ 0.080] (stream_id=1, noind=0) strict-transport-security: max-age=31536000 [ 0.080] recv HEADERS frame ; END_HEADERS (padlen=0) ; First response header [ 0.080] recv DATA frame [ 0.080] recv DATA frame [ 0.081] recv DATA frame [ 0.093] recv DATA frame [ 0.093] recv DATA frame [ 0.094] recv DATA frame [ 0.094] recv DATA frame [ 0.094] recv DATA frame [ 0.096] recv DATA frame [ 0.096] send WINDOW_UPDATE frame (window_size_increment=36554) [ 0.096] send WINDOW_UPDATE frame (window_size_increment=36554) [ 0.108] recv DATA frame [ 0.108] recv DATA frame ; END_STREAM [ 0.108] send GOAWAY frame (last_stream_id=0, error_code=NO_ERROR(0), opaque_data(0)=[]) The HTTP Upgrade is performed like this:: $ nghttp -nvu http://nghttp2.org [ 0.013] HTTP Upgrade request GET / HTTP/1.1 Host: nghttp2.org Connection: Upgrade, HTTP2-Settings Upgrade: h2c-14 HTTP2-Settings: AwAAAGQEAAD__wUAAAAB Accept: */* User-Agent: nghttp2/0.4.0-DEV [ 0.024] HTTP Upgrade response HTTP/1.1 101 Switching Protocols Connection: Upgrade Upgrade: h2c-14 [ 0.024] HTTP Upgrade success [ 0.024] send SETTINGS frame (niv=3) [SETTINGS_MAX_CONCURRENT_STREAMS(3):100] [SETTINGS_INITIAL_WINDOW_SIZE(4):65535] [SETTINGS_COMPRESS_DATA(5):1] [ 0.024] recv SETTINGS frame (niv=2) [SETTINGS_MAX_CONCURRENT_STREAMS(3):100] [SETTINGS_INITIAL_WINDOW_SIZE(4):65535] [ 0.024] send SETTINGS frame ; ACK (niv=0) [ 0.024] (stream_id=1, noind=0) :status: 200 [ 0.024] (stream_id=1, noind=0) accept-ranges: bytes [ 0.024] (stream_id=1, noind=0) age: 10 [ 0.024] (stream_id=1, noind=0) content-length: 40243 [ 0.024] (stream_id=1, noind=0) content-type: text/html [ 0.024] (stream_id=1, noind=0) date: Wed, 14 May 2014 15:16:34 GMT [ 0.024] (stream_id=1, noind=0) etag: "535d0eea-9d33" [ 0.024] (stream_id=1, noind=0) last-modified: Sun, 27 Apr 2014 14:06:34 GMT [ 0.024] (stream_id=1, noind=0) server: nginx/1.4.6 (Ubuntu) [ 0.024] (stream_id=1, noind=0) x-varnish: 2114900541 2114900540 [ 0.024] (stream_id=1, noind=0) via: 1.1 varnish, 1.1 nghttpx [ 0.024] recv HEADERS frame ; END_HEADERS (padlen=0) ; First response header [ 0.024] recv DATA frame [ 0.025] recv DATA frame [ 0.031] recv DATA frame [ 0.031] recv DATA frame [ 0.032] recv DATA frame [ 0.032] recv DATA frame [ 0.033] recv DATA frame [ 0.033] recv DATA frame [ 0.033] send WINDOW_UPDATE frame (window_size_increment=33164) [ 0.033] send WINDOW_UPDATE frame (window_size_increment=33164) [ 0.038] recv DATA frame [ 0.038] recv DATA frame [ 0.038] recv DATA frame ; END_STREAM [ 0.038] recv SETTINGS frame ; ACK (niv=0) [ 0.038] send GOAWAY frame (last_stream_id=0, error_code=NO_ERROR(0), opaque_data(0)=[]) Using the ``-s`` option, ``nghttp`` prints out some timing information for requests, sorted by completion time:: $ nghttp -nas https://nghttp2.org/ ***** Statistics ***** Request timing: complete: relative time from protocol handshake to stream close request: relative time from protocol handshake to request transmission. If '*' is shown, this was pushed by server. process: time for request and response code: HTTP status code size: number of bytes received as response body without inflation. URI: request URI sorted by 'complete' complete request process code size request path +11.07ms +120us 10.95ms 200 9K / +16.77ms * +8.80ms 7.98ms 200 8K /stylesheets/screen.css +27.00ms +11.16ms 15.84ms 200 3K /javascripts/octopress.js +27.40ms +11.16ms 16.24ms 200 3K /javascripts/modernizr-2.0.js +76.14ms +11.17ms 64.97ms 200 171K /images/posts/with-pri-blog.png +88.52ms +11.17ms 77.36ms 200 174K /images/posts/without-pri-blog.png Using the ``-r`` option, ``nghttp`` writes more detailed timing data to the given file in HAR format. nghttpd - server ++++++++++++++++ ``nghttpd`` is a multi-threaded static web server. By default, it uses SSL/TLS connection. Use ``--no-tls`` option to disable it. ``nghttpd`` only accepts HTTP/2 connections via NPN/ALPN or direct HTTP/2 connections. No HTTP Upgrade is supported. The ``-p`` option allows users to configure server push. Just like ``nghttp``, it has a verbose output mode for framing information. Here is sample output from ``nghttpd``:: $ nghttpd --no-tls -v 8080 IPv4: listen on port 8080 IPv6: listen on port 8080 [id=1] [ 15.921] send SETTINGS frame (niv=2) [SETTINGS_MAX_CONCURRENT_STREAMS(3):100] [SETTINGS_COMPRESS_DATA(5):1] [id=1] [ 15.921] recv SETTINGS frame (niv=3) [SETTINGS_MAX_CONCURRENT_STREAMS(3):100] [SETTINGS_INITIAL_WINDOW_SIZE(4):65535] [SETTINGS_COMPRESS_DATA(5):1] [id=1] [ 15.921] (stream_id=1, noind=0) :authority: localhost:8080 [id=1] [ 15.921] (stream_id=1, noind=0) :method: GET [id=1] [ 15.921] (stream_id=1, noind=0) :path: / [id=1] [ 15.921] (stream_id=1, noind=0) :scheme: http [id=1] [ 15.921] (stream_id=1, noind=0) accept: */* [id=1] [ 15.921] (stream_id=1, noind=0) accept-encoding: gzip, deflate [id=1] [ 15.921] (stream_id=1, noind=0) user-agent: nghttp2/0.4.0-DEV [id=1] [ 15.921] recv HEADERS frame ; END_STREAM | END_HEADERS (padlen=0) ; Open new stream [id=1] [ 15.921] recv SETTINGS frame ; ACK (niv=0) [id=1] [ 15.921] send SETTINGS frame ; ACK (niv=0) [id=1] [ 15.921] send HEADERS frame ; END_HEADERS (padlen=0) ; First response header :status: 200 cache-control: max-age=3600 content-length: 612 date: Wed, 14 May 2014 15:19:03 GMT last-modified: Sat, 08 Mar 2014 16:04:06 GMT server: nghttpd nghttp2/0.4.0-DEV [id=1] [ 15.922] send DATA frame ; COMPRESSED [id=1] [ 15.922] send DATA frame ; END_STREAM [id=1] [ 15.922] stream_id=1 closed [id=1] [ 15.922] recv GOAWAY frame (last_stream_id=0, error_code=NO_ERROR(0), opaque_data(0)=[]) [id=1] [ 15.922] closed nghttpx - proxy +++++++++++++++ ``nghttpx`` is a multi-threaded reverse proxy for HTTP/2, SPDY and HTTP/1.1, and powers http://nghttp2.org and supports HTTP/2 server push. ``nghttpx`` implements `important performance-oriented features `_ in TLS, such as session IDs, session tickets (with automatic key rotation), OCSP stapling, dynamic record sizing, ALPN/NPN, forward secrecy and SPDY & HTTP/2. ``nghttpx`` has several operational modes: ================== ============================ ============== ============= Mode option Frontend Backend Note ================== ============================ ============== ============= default mode HTTP/2, SPDY, HTTP/1.1 (TLS) HTTP/1.1 Reverse proxy ``--http2-proxy`` HTTP/2, SPDY, HTTP/1.1 (TLS) HTTP/1.1 SPDY proxy ``--http2-bridge`` HTTP/2, SPDY, HTTP/1.1 (TLS) HTTP/2 (TLS) ``--client`` HTTP/2, HTTP/1.1 HTTP/2 (TLS) ``--client-proxy`` HTTP/2, HTTP/1.1 HTTP/2 (TLS) Forward proxy ================== ============================ ============== ============= The interesting mode at the moment is the default mode. It works like a reverse proxy and listens for HTTP/2, SPDY and HTTP/1.1 and can be deployed as a 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 the ``--frontend-no-tls`` option. If that option is used, SPDY is disabled in the frontend and incoming HTTP/1.1 connections can be upgraded to HTTP/2 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 the ``--backend-no-tls`` option. ``nghttpx`` supports a configuration file. See the ``--conf`` option and sample configuration file ``nghttpx.conf.sample``. 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, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/1.1) --> Web Server [reverse proxy] With the ``--http2-proxy`` option, it works as a so called secure proxy (aka SPDY proxy):: Client <-- (HTTP/2, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/1.1) --> Proxy [secure proxy] (e.g., Squid, ATS) The ``Client`` in the above example 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. One way to configure Chrome to use a secure proxy is to create a proxy.pac script like this: .. code-block:: javascript function FindProxyForURL(url, host) { return "HTTPS SERVERADDR:PORT"; } ``SERVERADDR`` and ``PORT`` is the hostname/address and port of the machine nghttpx is running on. Please note that Chrome requires a 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, SPDY and HTTP/1.1 connections and communicates with the backend in HTTP/2:: Client <-- (HTTP/2, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/2) --> Web or HTTP/2 Proxy etc (e.g., nghttpx -s) With ``--client-proxy``, it works as a forward proxy and expects that the backend is an HTTP/2 proxy:: Client <-- (HTTP/2, HTTP/1.1) --> nghttpx <-- (HTTP/2) --> HTTP/2 Proxy [forward proxy] (e.g., nghttpx -s) The ``Client`` needs to be configured to use nghttpx as a forward proxy. The frontend HTTP/1.1 connection can be upgraded to HTTP/2 through HTTP Upgrade. With the above configuration, one can use HTTP/1.1 client to access and test their HTTP/2 servers. With ``--client``, it works as a reverse proxy and expects that the backend is an HTTP/2 Web server:: Client <-- (HTTP/2, HTTP/1.1) --> nghttpx <-- (HTTP/2) --> Web Server [reverse proxy] The frontend HTTP/1.1 connection can be upgraded to HTTP/2 through HTTP Upgrade. For the operation modes which talk to the backend in HTTP/2 over SSL/TLS, the backend connections can be tunneled through an HTTP proxy. The proxy is specified using ``--backend-http-proxy-uri``. The following figure illustrates the example of the ``--http2-bridge`` and ``--backend-http-proxy-uri`` options to talk to the outside HTTP/2 proxy through an HTTP proxy:: Client <-- (HTTP/2, SPDY, HTTP/1.1) --> nghttpx <-- (HTTP/2) -- --===================---> HTTP/2 Proxy (HTTP proxy tunnel) (e.g., nghttpx -s) Benchmarking tool ----------------- The ``h2load`` program is a benchmarking tool for HTTP/2 and SPDY. The SPDY support is enabled if the program was built with the spdylay library. The UI of ``h2load`` is heavily inspired by ``weighttp`` (https://github.com/lighttpd/weighttp). The typical usage is as follows:: $ h2load -n100000 -c100 -m100 https://localhost:8443/ starting benchmark... spawning thread #0: 100 concurrent clients, 100000 total requests Protocol: TLSv1.2 Cipher: ECDHE-RSA-AES128-GCM-SHA256 progress: 10% done progress: 20% done progress: 30% done progress: 40% done progress: 50% done progress: 60% done progress: 70% done progress: 80% done progress: 90% done progress: 100% done finished in 7.10s, 14092 req/s, 55.67MB/s requests: 100000 total, 100000 started, 100000 done, 100000 succeeded, 0 failed, 0 errored status codes: 100000 2xx, 0 3xx, 0 4xx, 0 5xx traffic: 414200800 bytes total, 2723100 bytes headers, 409600000 bytes data min max mean sd +/- sd time for request: 283.86ms 1.46s 659.70ms 150.87ms 84.68% The above example issued total 100,000 requests, using 100 concurrent clients (in other words, 100 HTTP/2 sessions), and a maximum of 100 streams per client. With the ``-t`` option, ``h2load`` will use multiple native threads to avoid saturating a single core on client side. .. warning:: **Don't use this tool against publicly available servers.** That is considered a DOS attack. Please only use it against your private servers. HPACK tools ----------- The ``src`` directory contains the HPACK tools. The ``deflatehd`` program is a command-line header compression tool. The ``inflatehd`` program is a command-line header decompression tool. Both tools read input from stdin and write output to stdout. Errors are written to stderr. They take JSON as input and output. We (mostly) use the same JSON data format described at https://github.com/http2jp/hpack-test-case. deflatehd - header compressor +++++++++++++++++++++++++++++ The ``deflatehd`` program reads JSON data or HTTP/1-style header fields from stdin and outputs compressed header block in JSON. For the JSON input, the root JSON object must include a ``cases`` key. Its value has to include the sequence of input header set. They share the same compression context and are processed in the order they appear. Each item in the sequence is a JSON object and it must include a ``headers`` key. Its value is an array of JSON objects, which includes exactly one name/value pair. Example: .. code-block:: json { "cases": [ { "headers": [ { ":method": "GET" }, { ":path": "/" } ] }, { "headers": [ { ":method": "POST" }, { ":path": "/" } ] } ] } With the ``-t`` option, the program can accept more familiar HTTP/1 style header field blocks. Each header set is delimited by an empty line: Example:: :method: GET :scheme: https :path: / :method: POST user-agent: nghttp2 The output is in JSON object. It should include a ``cases`` key and its value is an array of JSON objects, which has at least the following keys: seq The index of header set in the input. input_length The sum of the length of the name/value pairs in the input. output_length The length of the compressed header block. percentage_of_original_size ``input_length`` / ``output_length`` * 100 wire The compressed header block as a hex string. headers The input header set. header_table_size The header table size adjusted before deflating the header set. Examples: .. code-block:: json { "cases": [ { "seq": 0, "input_length": 66, "output_length": 20, "percentage_of_original_size": 30.303030303030305, "wire": "01881f3468e5891afcbf83868a3d856659c62e3f", "headers": [ { ":authority": "example.org" }, { ":method": "GET" }, { ":path": "/" }, { ":scheme": "https" }, { "user-agent": "nghttp2" } ], "header_table_size": 4096 } , { "seq": 1, "input_length": 74, "output_length": 10, "percentage_of_original_size": 13.513513513513514, "wire": "88448504252dd5918485", "headers": [ { ":authority": "example.org" }, { ":method": "POST" }, { ":path": "/account" }, { ":scheme": "https" }, { "user-agent": "nghttp2" } ], "header_table_size": 4096 } ] } The output can be used as the input for ``inflatehd`` and ``deflatehd``. With the ``-d`` option, the extra ``header_table`` key is added and its associated value includes the state of dynamic header table after the corresponding header set was processed. The value includes at least the following keys: entries The entry in the header table. If ``referenced`` is ``true``, it is in the reference set. The ``size`` includes the overhead (32 bytes). The ``index`` corresponds to the index of header table. The ``name`` is the header field name and the ``value`` is the header field value. size The sum of the spaces entries occupied, this includes the entry overhead. max_size The maximum header table size. deflate_size The sum of the spaces entries occupied within ``max_deflate_size``. max_deflate_size The maximum header table size the encoder uses. This can be smaller than ``max_size``. In this case, the encoder only uses up to first ``max_deflate_size`` buffer. Since the header table size is still ``max_size``, the encoder has to keep track of entries ouside the ``max_deflate_size`` but inside the ``max_size`` and make sure that they are no longer referenced. Example: .. code-block:: json { "cases": [ { "seq": 0, "input_length": 66, "output_length": 20, "percentage_of_original_size": 30.303030303030305, "wire": "01881f3468e5891afcbf83868a3d856659c62e3f", "headers": [ { ":authority": "example.org" }, { ":method": "GET" }, { ":path": "/" }, { ":scheme": "https" }, { "user-agent": "nghttp2" } ], "header_table_size": 4096, "header_table": { "entries": [ { "index": 1, "name": "user-agent", "value": "nghttp2", "referenced": true, "size": 49 }, { "index": 2, "name": ":scheme", "value": "https", "referenced": true, "size": 44 }, { "index": 3, "name": ":path", "value": "/", "referenced": true, "size": 38 }, { "index": 4, "name": ":method", "value": "GET", "referenced": true, "size": 42 }, { "index": 5, "name": ":authority", "value": "example.org", "referenced": true, "size": 53 } ], "size": 226, "max_size": 4096, "deflate_size": 226, "max_deflate_size": 4096 } } , { "seq": 1, "input_length": 74, "output_length": 10, "percentage_of_original_size": 13.513513513513514, "wire": "88448504252dd5918485", "headers": [ { ":authority": "example.org" }, { ":method": "POST" }, { ":path": "/account" }, { ":scheme": "https" }, { "user-agent": "nghttp2" } ], "header_table_size": 4096, "header_table": { "entries": [ { "index": 1, "name": ":method", "value": "POST", "referenced": true, "size": 43 }, { "index": 2, "name": "user-agent", "value": "nghttp2", "referenced": true, "size": 49 }, { "index": 3, "name": ":scheme", "value": "https", "referenced": true, "size": 44 }, { "index": 4, "name": ":path", "value": "/", "referenced": false, "size": 38 }, { "index": 5, "name": ":method", "value": "GET", "referenced": false, "size": 42 }, { "index": 6, "name": ":authority", "value": "example.org", "referenced": true, "size": 53 } ], "size": 269, "max_size": 4096, "deflate_size": 269, "max_deflate_size": 4096 } } ] } inflatehd - header decompressor +++++++++++++++++++++++++++++++ The ``inflatehd`` program reads JSON data from stdin and outputs decompressed name/value pairs in JSON. The root JSON object must include the ``cases`` key. Its value has to include the sequence of compressed header blocks. They share the same compression context and are processed in the order they appear. Each item in the sequence is a JSON object and it must have at least a ``wire`` key. Its value is a compressed header block as a hex string. Example: .. code-block:: json { "cases": [ { "wire": "8285" }, { "wire": "8583" } ] } The output is a JSON object. It should include a ``cases`` key and its value is an array of JSON objects, which has at least following keys: seq The index of the header set in the input. headers A JSON array that includes decompressed name/value pairs. wire The compressed header block as a hex string. header_table_size The header table size adjusted before inflating compressed header block. Example: .. code-block:: json { "cases": [ { "seq": 0, "wire": "01881f3468e5891afcbf83868a3d856659c62e3f", "headers": [ { ":authority": "example.org" }, { ":method": "GET" }, { ":path": "/" }, { ":scheme": "https" }, { "user-agent": "nghttp2" } ], "header_table_size": 4096 } , { "seq": 1, "wire": "88448504252dd5918485", "headers": [ { ":method": "POST" }, { ":path": "/account" }, { "user-agent": "nghttp2" }, { ":scheme": "https" }, { ":authority": "example.org" } ], "header_table_size": 4096 } ] } The output can be used as the input for ``deflatehd`` and ``inflatehd``. With the ``-d`` option, the extra ``header_table`` key is added and its associated value includes the state of the dynamic header table after the corresponding header set was processed. The format is the same as ``deflatehd``. libnghttp2_asio: High level HTTP/2 C++ library ---------------------------------------------- libnghttp2_asio is C++ library built on top of libnghttp2 and provides high level abstraction API to build HTTP/2 applications. It depends on the Boost::ASIO library and OpenSSL. Currently libnghttp2_asio provides both client and server APIs. libnghttp2_asio is not built by default. Use the ``--enable-asio-lib`` configure flag to build libnghttp2_asio. The required Boost libraries are: * Boost::Asio * Boost::System * Boost::Thread The server API is designed to build an HTTP/2 server very easily to utilize C++11 anonymous functions and closures. The bare minimum example of an HTTP/2 server looks like this: .. code-block:: cpp #include using namespace nghttp2::asio_http2; using namespace nghttp2::asio_http2::server; int main(int argc, char *argv[]) { boost::system::error_code ec; http2 server; server.handle("/", [](const request &req, const response &res) { res.write_head(200); res.end("hello, world\n"); }); if (server.listen_and_serve(ec, "localhost", "3000")) { std::cerr << "error: " << ec.message() << std::endl; } } Here is sample code to use the client API: .. code-block:: cpp #include #include using boost::asio::ip::tcp; using namespace nghttp2::asio_http2; using namespace nghttp2::asio_http2::client; int main(int argc, char *argv[]) { boost::system::error_code ec; boost::asio::io_service io_service; // connect to localhost:3000 session sess(io_service, "localhost", "3000"); sess.on_connect([&sess](tcp::resolver::iterator endpoint_it) { boost::system::error_code ec; auto req = sess.submit(ec, "GET", "http://localhost:3000/"); req->on_response([](const response &res) { // print status code and response header fields. std::cerr << "HTTP/2 " << res.status_code() << std::endl; for (auto &kv : res.header()) { std::cerr << kv.first << ": " << kv.second.value << "\n"; } std::cerr << std::endl; res.on_data([](const uint8_t *data, std::size_t len) { std::cerr.write(reinterpret_cast(data), len); std::cerr << std::endl; }); }); req->on_close([&sess](uint32_t error_code) { // shutdown session after first request was done. sess.shutdown(); }); }); sess.on_error([](const boost::system::error_code &ec) { std::cerr << "error: " << ec.message() << std::endl; }); io_service.run(); } For more details, see the documentation of libnghttp2_asio. Python bindings --------------- The ``python`` directory contains nghttp2 Python bindings. The bindings currently provide HPACK compressor and decompressor classes and an HTTP/2 server. The extension module is called ``nghttp2``. ``make`` will build the bindings and target Python version is determined by the ``configure`` script. If the detected Python version is not what you expect, specify a path to Python executable in a ``PYTHON`` variable as an argument to configure script (e.g., ``./configure PYTHON=/usr/bin/python3.4``). The following example code illustrates basic usage of the HPACK compressor and decompressor in Python: .. code-block:: python import binascii import nghttp2 deflater = nghttp2.HDDeflater() inflater = nghttp2.HDInflater() data = deflater.deflate([(b'foo', b'bar'), (b'baz', b'buz')]) print(binascii.b2a_hex(data)) hdrs = inflater.inflate(data) print(hdrs) The ``nghttp2.HTTP2Server`` class builds on top of the asyncio event loop. On construction, *RequestHandlerClass* must be given, which must be a subclass of ``nghttp2.BaseRequestHandler`` class. The ``BaseRequestHandler`` class is used to handle the HTTP/2 stream. By default, it does nothing. It must be subclassed to handle each event callback method. The first callback method invoked is ``on_headers()``. It is called when HEADERS frame, which includes the request header fields, has arrived. If the request has a request body, ``on_data(data)`` is invoked for each chunk of received data. Once the entire request is received, ``on_request_done()`` is invoked. When the stream is closed, ``on_close(error_code)`` is called. The application can send a response using ``send_response()`` method. It can be used in ``on_headers()``, ``on_data()`` or ``on_request_done()``. The application can push resources using the ``push()`` method. It must be used before the ``send_response()`` call. The following instance variables are available: client_address Contains a tuple of the form (host, port) referring to the client's address. stream_id Stream ID of this stream. scheme Scheme of the request URI. This is a value of :scheme header field. method Method of this stream. This is a value of :method header field. host This is a value of :authority or host header field. path This is a value of :path header field. The following example illustrates the HTTP2Server and BaseRequestHandler usage: .. code-block:: python #!/usr/bin/env python import io, ssl import nghttp2 class Handler(nghttp2.BaseRequestHandler): def on_headers(self): self.push(path='/css/bootstrap.css', request_headers = [('content-length', '3')], status=200, body='foo') self.push(path='/js/bootstrap.js', method='GET', request_headers = [('content-length', '10')], status=200, body='foobarbuzz') self.send_response(status=200, headers = [('content-type', 'text/plain')], body=io.BytesIO(b'nghttp2-python FTW')) ctx = ssl.SSLContext(ssl.PROTOCOL_SSLv23) ctx.options = ssl.OP_ALL | ssl.OP_NO_SSLv2 ctx.load_cert_chain('server.crt', 'server.key') # give None to ssl to make the server non-SSL/TLS server = nghttp2.HTTP2Server(('127.0.0.1', 8443), Handler, ssl=ctx) server.serve_forever() Contribution ------------ [This text was composed based on 1.2. License section of curl/libcurl project.] When contributing with code, you agree to put your changes and new code under the same license nghttp2 is already using unless stated and agreed otherwise. When changing existing source code, do not alter the copyright of the original file(s). The copyright will still be owned by the original creator(s) or those who have been assigned copyright by the original author(s). By submitting a patch to the nghttp2 project, you (or your employer, as the case may be) agree to assign the copyright of your submission to us. .. the above really needs to be reworded to pass legal muster. We will credit you for your changes as far as possible, to give credit but also to keep a trace back to who made what changes. Please always provide us with your full real name when contributing! See `Contribution Guidelines `_ for more details.