Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

243 lines (222 sloc) 10.291 kb
% ==========================================================================================================
% MISULTIN - WebSocket
%
% >-|-|-(°>
%
% Copyright (C) 2011, Roberto Ostinelli <roberto@ostinelli.net>.
% All rights reserved.
%
% Code portions from Joe Armstrong have been originally taken under MIT license at the address:
% <http://armstrongonsoftware.blogspot.com/2009/12/comet-is-dead-long-live-websockets.html>
%
% BSD License
%
% Redistribution and use in source and binary forms, with or without modification, are permitted provided
% that the following conditions are met:
%
% * Redistributions of source code must retain the above copyright notice, this list of conditions and the
% following disclaimer.
% * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and
% the following disclaimer in the documentation and/or other materials provided with the distribution.
% * Neither the name of the authors nor the names of its contributors may be used to endorse or promote
% products derived from this software without specific prior written permission.
%
% THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
% WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
% PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
% ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
% TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
% HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
% NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
% POSSIBILITY OF SUCH DAMAGE.
% ==========================================================================================================
-module(misultin_websocket).
-vsn("0.9-dev").
% API
-export([check/3, connect/4]).
-export([check_headers/2, websocket_close/4, ws_loop/3, send_to_browser/2, get_wsinfo/2]).
% behaviour
-export([behaviour_info/1]).
% includes
-include("../include/misultin.hrl").
% ============================ \/ API ======================================================================
% Check if the incoming request is a websocket handshake.
-spec check(WsVersions::[websocket_version()], Path::string(), Headers::http_headers()) -> false | {true, Vsn::websocket_version()}.
check(WsVersions, _Path, Headers) ->
?LOG_DEBUG("testing for a websocket request path: ~p headers: ~p", [_Path, Headers]),
% checks
check_websockets(WsVersions, Headers).
% Connect and handshake with Websocket.
-spec connect(ServerRef::pid(), Req::#req{}, Ws::#ws{}, WsLoop::function()) -> true.
connect(ServerRef, #req{headers = Headers} = Req, #ws{vsn = Vsn, socket = Socket, socket_mode = SocketMode, path = Path} = Ws, WsLoop) ->
?LOG_DEBUG("building handshake response", []),
% get data
Origin = misultin_utility:header_get_value('Origin', Headers),
Host = misultin_utility:header_get_value('Host', Headers),
% build handshake
VsnMod = get_module_name_from_vsn(Vsn),
HandshakeServer = VsnMod:handshake(Req, Headers, {Path, Origin, Host}),
% send handshake back
misultin_socket:send(Socket, HandshakeServer, SocketMode),
% add data to ws record and spawn_link controlling process
WsT = {misultin_ws, self()},
WsHandleLoopPid = spawn_link(fun() -> WsLoop(WsT) end),
% trap exit
process_flag(trap_exit, true),
% set opts
misultin_socket:setopts(Socket, [{packet, 0}], SocketMode),
% add main websocket pid to misultin server reference
misultin_server:ws_pid_ref_add(ServerRef, self()),
% enter loop
enter_loop(WsHandleLoopPid, Ws, Req#req.headers, Origin, Host).
% Check if headers correspond to headers requirements.
-spec check_headers(Headers::http_headers(), RequiredHeaders::http_headers()) -> true | http_headers().
check_headers(Headers, RequiredHeaders) ->
F = fun({Tag, Val}) ->
% see if the required Tag is in the Headers
case misultin_utility:header_get_value(Tag, Headers) of
false -> true; % header not found, keep in list
HVal ->
case Val of
ignore -> false; % ignore value -> ok, remove from list
HVal -> false; % expected val -> ok, remove from list
_ ->
% check if header has multiple parameters (for instance FF7 websockets)
not(lists:member(Val,string:tokens(HVal,", ")))
end
end
end,
case lists:filter(F, RequiredHeaders) of
[] -> true;
MissingHeaders -> MissingHeaders
end.
% Close socket and custom handling loop dependency
-spec websocket_close(Socket::socket(), WsHandleLoopPid::pid(), SocketMode::socketmode(), WsAutoExit::boolean()) -> ok.
websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit) ->
case WsAutoExit of
true ->
% kill custom handling loop process
exit(WsHandleLoopPid, kill);
false ->
% the killing of the custom handling loop process is handled in the loop itself -> send event
WsHandleLoopPid ! closed
end,
% close main socket
misultin_socket:close(Socket, SocketMode).
% send to browser
-spec send_to_browser(WsHandleLoopPid::pid(), Data::iolist() | binary()) -> {browser, Data::list()}.
send_to_browser(WsHandleLoopPid, Data) ->
WsHandleLoopPid ! {browser, Data}.
% get ws info from websocket process handler
-spec get_wsinfo(SocketPid::pid(), WsInfo::atom()) -> term().
get_wsinfo(SocketPid, WsInfo) ->
misultin_utility:call(SocketPid, {wsinfo, WsInfo}).
% ============================ /\ API ======================================================================
% ============================ \/ INTERNAL FUNCTIONS =======================================================
% behaviour
behaviour_info(callbacks) ->
[
{check_websocket, 1},
{handshake, 3},
{handle_data, 3},
{send_format, 2}
];
behaviour_info(_) ->
undefined.
% Loop to check for all available supported websocket protocols.
-spec check_websockets(VsnSupported::[websocket_version()], Headers::http_headers()) -> false | {true, Vsn::websocket_version()}.
check_websockets([], _Headers) -> false;
check_websockets([Vsn|T], Headers) ->
?LOG_DEBUG("testing for websocket protocol ~p", [Vsn]),
VsnMod = get_module_name_from_vsn(Vsn),
case VsnMod:check_websocket(Headers) of
false -> check_websockets(T, Headers);
true -> {true, Vsn}
end.
% enter loop
-spec enter_loop(WsHandleLoopPid::pid(), Ws::#ws{}, Headers::http_headers(), Origin::string(), Host::string()) -> true.
enter_loop(WsHandleLoopPid, Ws, Headers, Origin, Host) ->
% start listening for incoming data
ws_loop(WsHandleLoopPid, Ws#ws{headers = Headers, origin = Origin, host = Host}, undefined),
% unlink
process_flag(trap_exit, false),
erlang:unlink(WsHandleLoopPid).
% Main Websocket loop
-spec ws_loop(
WsHandleLoopPid::pid(),
Ws::#ws{},
State::term()) -> ok.
ws_loop(WsHandleLoopPid, #ws{vsn = Vsn, socket = Socket, socket_mode = SocketMode, ws_autoexit = WsAutoExit} = Ws, State) ->
misultin_socket:setopts(Socket, [{active, once}], SocketMode),
receive
{tcp, Socket, Data} ->
VsnMod = get_module_name_from_vsn(Vsn),
case VsnMod:handle_data(Data, State, {Socket, SocketMode, WsHandleLoopPid}) of
websocket_close ->
misultin_websocket:websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit);
{websocket_close, CloseData} ->
misultin_socket:send(Socket, CloseData, SocketMode),
misultin_websocket:websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit);
NewState ->
ws_loop(WsHandleLoopPid, Ws, NewState)
end;
{ssl, Socket, Data} ->
VsnMod = get_module_name_from_vsn(Vsn),
case VsnMod:handle_data(Data, State, {Socket, SocketMode, WsHandleLoopPid}) of
{command, websocket_close} ->
misultin_websocket:websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit);
NewState ->
ws_loop(WsHandleLoopPid, Ws, NewState)
end;
{WsHandleLoopPid, {wsinfo, WsInfo}} ->
WsResponse = case WsInfo of
raw -> Ws;
socket -> Ws#ws.socket;
socket_mode -> Ws#ws.socket_mode;
peer_addr -> Ws#ws.peer_addr;
peer_port -> Ws#ws.peer_port;
peer_cert -> Ws#ws.peer_cert;
vsn -> Ws#ws.vsn;
origin -> Ws#ws.origin;
host -> Ws#ws.host;
path -> Ws#ws.path;
headers -> Ws#ws.headers
end,
?LOG_DEBUG("received ws info for: ~p, responding with ~p", [WsInfo, WsResponse]),
misultin_utility:respond(WsHandleLoopPid, WsResponse),
ws_loop(WsHandleLoopPid, Ws, State);
{tcp_closed, Socket} ->
?LOG_DEBUG("tcp connection was closed, exit", []),
% close websocket and custom controlling loop
websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit);
{ssl_closed, Socket} ->
?LOG_DEBUG("ssl tcp connection was closed, exit", []),
% close websocket and custom controlling loop
websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit);
{'EXIT', WsHandleLoopPid, Reason} ->
case Reason of
normal ->
?LOG_DEBUG("linked websocket controlling loop stopped.", []);
_ ->
?LOG_ERROR("linked websocket controlling loop crashed with reason: ~p", [Reason])
end,
% close websocket and custom controlling loop
websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit);
{send, Data} ->
VsnMod = get_module_name_from_vsn(Vsn),
?LOG_DEBUG("sending data: ~p to websocket module: ~p", [Data, VsnMod]),
misultin_socket:send(Socket, VsnMod:send_format(Data, State), SocketMode),
ws_loop(WsHandleLoopPid, Ws, State);
shutdown ->
?LOG_DEBUG("shutdown request received, closing websocket with pid ~p", [self()]),
% close websocket and custom controlling loop
websocket_close(Socket, WsHandleLoopPid, SocketMode, WsAutoExit);
_Ignored ->
?LOG_WARNING("received unexpected message, ignoring: ~p", [_Ignored]),
ws_loop(WsHandleLoopPid, Ws, State)
end.
% convert websocket version to module name
-spec get_module_name_from_vsn(Vsn::websocket_version()) -> atom().
get_module_name_from_vsn(Vsn) ->
list_to_atom("misultin_websocket_" ++ atom_to_list(Vsn)).
% ============================ /\ INTERNAL FUNCTIONS =======================================================
Jump to Line
Something went wrong with that request. Please try again.