1The nghttp Instruction 2============================= 3 4This is an implementation of the Hypertext Transfer Protocol version 2 in C. 5 6The framing layer of HTTP/2 is implemented as a reusable C library. 7 8An HPACK encoder and decoder are available as a public API. 9 10- The nghttp support many different processor, but for the most part you only need the following functions: 11 12 **nghttp2_session_callbacks_new**: Initializes \*callbacks_ptr with NULL values 13 14 **nghttp2_session_client_new**: Initializes \*session_ptr for client use 15 16 **nghttp2_session_callbacks_del**: Frees any resources allocated for callbacks 17 18 **nghttp2_submit_settings**: Stores local settings and submits SETTINGS frame 19 20 **nghttp2_submit_request**: Submits HEADERS frame and optionally one or more DATA frames 21 22 **nghttp2_session_want_read**: Returns nonzero value if session wants to receive data from the remote peer 23 24 **nghttp2_session_want_write**: Returns nonzero value if session wants to send data to the remote peer 25 26 **nghttp2_session_recv**: Receives frames from the remote peer 27 28 **nghttp2_session_send**: Sends pending frames to the remote peer 29 30 **nghttp2_session_del**: Frees any resources allocated for session 31 32If you are following TLS related RFC, you know that NPN is not the standardized way to negotiate HTTP/2. NPN itself is not even published as RFC. 33 34The standard way to negotiate HTTP/2 is ALPN, Application-Layer Protocol Negotiation Extension, defined in RFC 7301. 35 36- The following endpoints are available to try out the nghttp2 implementation: 37 38 https://nghttp2.org/ (TLS + ALPN/NPN) 39 40 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. 41 42More information about nghttp library can be found at https://nghttp2.org 43 44An introductory article on protocol is available on RFC 7540 HTTP/2 and RFC 7541 HPACK - Header Compression for HTTP/2 45