%% Copyright (c) 2011, Loïc Hoguin %% %% Permission to use, copy, modify, and/or distribute this software for any %% purpose with or without fee is hereby granted, provided that the above %% copyright notice and this permission notice appear in all copies. %% %% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES %% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF %% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR %% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES %% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN %% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF %% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. -module(cowboy_http_protocol). -export([start_link/3]). %% API. -export([init/3, wait_request/1]). %% FSM. -include("include/types.hrl"). -include("include/http.hrl"). -record(state, { socket :: socket(), transport :: module(), dispatch :: dispatch(), handler :: {Handler::module(), Opts::term()}, timeout :: timeout(), connection = keepalive :: keepalive | close }). %% API. -spec start_link(Socket::socket(), Transport::module(), Opts::term()) -> {ok, Pid::pid()}. start_link(Socket, Transport, Opts) -> Pid = spawn_link(?MODULE, init, [Socket, Transport, Opts]), {ok, Pid}. %% FSM. -spec init(Socket::socket(), Transport::module(), Opts::term()) -> ok. init(Socket, Transport, Opts) -> Dispatch = proplists:get_value(dispatch, Opts, []), Timeout = proplists:get_value(timeout, Opts, 5000), wait_request(#state{socket=Socket, transport=Transport, dispatch=Dispatch, timeout=Timeout}). -spec wait_request(State::#state{}) -> ok. wait_request(State=#state{socket=Socket, transport=Transport, timeout=T}) -> Transport:setopts(Socket, [{packet, http}]), case Transport:recv(Socket, 0, T) of {ok, Request} -> request(Request, State); {error, timeout} -> error_terminate(408, State); {error, closed} -> terminate(State) end. -spec request({http_request, Method::http_method(), URI::http_uri(), Version::http_version()}, State::#state{}) -> ok. %% @todo We probably want to handle some things differently between versions. request({http_request, _Method, _URI, Version}, State) when Version =/= {1, 0}, Version =/= {1, 1} -> error_terminate(505, State); %% @todo We need to cleanup the URI properly. request({http_request, Method, {abs_path, AbsPath}, Version}, State=#state{socket=Socket, transport=Transport}) -> {Path, RawPath, Qs} = cowboy_dispatcher:split_path(AbsPath), ConnAtom = version_to_connection(Version), wait_header(#http_req{socket=Socket, transport=Transport, connection=ConnAtom, method=Method, version=Version, path=Path, raw_path=RawPath, raw_qs=Qs}, State#state{connection=ConnAtom}); request({http_request, Method, '*', Version}, State=#state{socket=Socket, transport=Transport}) -> ConnAtom = version_to_connection(Version), wait_header(#http_req{socket=Socket, transport=Transport, connection=ConnAtom, method=Method, version=Version, path='*', raw_path="*", raw_qs=[]}, State#state{connection=ConnAtom}); request({http_request, _Method, _URI, _Version}, State) -> error_terminate(501, State); request({http_error, "\r\n"}, State) -> wait_request(State); request({http_error, _Any}, State) -> error_terminate(400, State). -spec wait_header(Req::#http_req{}, State::#state{}) -> ok. %% @todo We don't want to wait T at each header... %% We want to wait T total until we reach the body. wait_header(Req, State=#state{socket=Socket, transport=Transport, timeout=T}) -> case Transport:recv(Socket, 0, T) of {ok, Header} -> header(Header, Req, State); {error, timeout} -> error_terminate(408, State); {error, closed} -> terminate(State) end. -spec header({http_header, I::integer(), Field::http_header(), R::term(), Value::string()} | http_eoh, Req::#http_req{}, State::#state{}) -> ok. header({http_header, _I, 'Host', _R, RawHost}, Req=#http_req{path=Path, host=undefined}, State=#state{dispatch=Dispatch}) -> RawHost2 = string_to_lower(RawHost), Host = cowboy_dispatcher:split_host(RawHost2), %% @todo We probably want to filter the Host and Path here to allow %% things like url rewriting. case cowboy_dispatcher:match(Host, Path, Dispatch) of {ok, Handler, Opts, Binds} -> wait_header(Req#http_req{ host=Host, raw_host=RawHost2, bindings=Binds, headers=[{'Host', RawHost2}|Req#http_req.headers]}, State#state{handler={Handler, Opts}}); {error, notfound, host} -> error_terminate(400, State); {error, notfound, path} -> error_terminate(404, State) end; %% Ignore Host headers if we already have it. header({http_header, _I, 'Host', _R, _V}, Req, State) -> wait_header(Req, State); header({http_header, _I, 'Connection', _R, Connection}, Req, State) -> ConnAtom = connection_to_atom(Connection), wait_header(Req#http_req{connection=ConnAtom, headers=[{'Connection', Connection}|Req#http_req.headers]}, State#state{connection=ConnAtom}); header({http_header, _I, Field, _R, Value}, Req, State) -> wait_header(Req#http_req{headers=[{Field, Value}|Req#http_req.headers]}, State); %% The Host header is required. header(http_eoh, #http_req{host=undefined}, State) -> error_terminate(400, State); header(http_eoh, Req, State) -> handler_init(Req, State); header({http_error, _String}, _Req, State) -> error_terminate(500, State). -spec handler_init(Req::#http_req{}, State::#state{}) -> ok. handler_init(Req, State=#state{ transport=Transport, handler={Handler, Opts}}) -> case catch Handler:init({Transport:name(), http}, Req, Opts) of {ok, Req, HandlerState} -> handler_loop(HandlerState, Req, State); %% @todo {upgrade, transport, Module} {upgrade, protocol, Module} -> Module:upgrade(Handler, Opts, Req); {'EXIT', _Reason} -> error_terminate(500, State) end. -spec handler_loop(HandlerState::term(), Req::#http_req{}, State::#state{}) -> ok. handler_loop(HandlerState, Req, State=#state{handler={Handler, _Opts}}) -> case catch Handler:handle(Req#http_req{resp_state=waiting}, HandlerState) of {ok, Req2, HandlerState2} -> handler_terminate(HandlerState2, Req2, State); {'EXIT', _Reason} -> terminate(State) end. -spec handler_terminate(HandlerState::term(), Req::#http_req{}, State::#state{}) -> ok. handler_terminate(HandlerState, Req, State=#state{handler={Handler, _Opts}}) -> HandlerRes = (catch Handler:terminate( Req#http_req{resp_state=locked}, HandlerState)), BodyRes = ensure_body_processed(Req), ensure_response(Req, State), case {HandlerRes, BodyRes, State#state.connection} of {ok, ok, keepalive} -> next_request(State); _Closed -> terminate(State) end. -spec ensure_body_processed(Req::#http_req{}) -> ok | close. ensure_body_processed(#http_req{body_state=done}) -> ok; ensure_body_processed(Req=#http_req{body_state=waiting}) -> case cowboy_http_req:body(Req) of {error, badarg} -> ok; %% No body. {error, _Reason} -> close; _Any -> ok end. -spec ensure_response(Req::#http_req{}, State::#state{}) -> ok. %% The handler has already fully replied to the client. ensure_response(#http_req{resp_state=done}, _State) -> ok; %% No response has been sent but everything apparently went fine. %% Reply with 204 No Content to indicate this. ensure_response(#http_req{resp_state=waiting}, State) -> error_response(204, State). -spec error_response(Code::http_status(), State::#state{}) -> ok. error_response(Code, #state{socket=Socket, transport=Transport, connection=Connection}) -> _ = cowboy_http_req:reply(Code, [], [], #http_req{ socket=Socket, transport=Transport, connection=Connection, resp_state=waiting}), ok. -spec error_terminate(Code::http_status(), State::#state{}) -> ok. error_terminate(Code, State) -> error_response(Code, State#state{connection=close}), terminate(State). -spec terminate(State::#state{}) -> ok. terminate(#state{socket=Socket, transport=Transport}) -> Transport:close(Socket), ok. -spec next_request(State::#state{}) -> ok. next_request(State=#state{connection=keepalive}) -> ?MODULE:wait_request(State); next_request(State=#state{connection=close}) -> terminate(State). %% Internal. -spec version_to_connection(Version::http_version()) -> keepalive | close. version_to_connection({1, 1}) -> keepalive; version_to_connection(_Any) -> close. -spec connection_to_atom(Connection::string()) -> keepalive | close. connection_to_atom("keep-alive") -> keepalive; connection_to_atom("close") -> close; connection_to_atom(Connection) -> case string_to_lower(Connection) of "close" -> close; _Any -> keepalive end. %% More efficient implementation of string:to_lower. %% We are excluding a few characters on purpose. -spec string_to_lower(string()) -> string(). string_to_lower(L) -> [char_to_lower(C) || C <- L]. %% We gain noticeable speed by matching each value directly. -spec char_to_lower(char()) -> char(). char_to_lower($A) -> $a; char_to_lower($B) -> $b; char_to_lower($C) -> $c; char_to_lower($D) -> $d; char_to_lower($E) -> $e; char_to_lower($F) -> $f; char_to_lower($G) -> $g; char_to_lower($H) -> $h; char_to_lower($I) -> $i; char_to_lower($J) -> $j; char_to_lower($K) -> $k; char_to_lower($L) -> $l; char_to_lower($M) -> $m; char_to_lower($N) -> $n; char_to_lower($O) -> $o; char_to_lower($P) -> $p; char_to_lower($Q) -> $q; char_to_lower($R) -> $r; char_to_lower($S) -> $s; char_to_lower($T) -> $t; char_to_lower($U) -> $u; char_to_lower($V) -> $v; char_to_lower($W) -> $w; char_to_lower($X) -> $x; char_to_lower($Y) -> $y; char_to_lower($Z) -> $z; char_to_lower(Ch) -> Ch.