From 8b9d9937dc4c2a0f8c849b965efed560fa469904 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= Date: Fri, 28 Apr 2017 11:28:41 +0200 Subject: Add Gun Websocket handlers and protocol support This functionality can be used to implement custom protocols on top of Websocket, but may also be used to decode frame contents on the fly if necessary. The default_protocol option defines what module should be used when no protocol was selected. The protocols option is a list of key/value pairs used to select the handler depending on the protocol that the server accepted. The feature is currently experimental. --- src/gun_http.erl | 73 +++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 46 insertions(+), 27 deletions(-) (limited to 'src/gun_http.erl') diff --git a/src/gun_http.erl b/src/gun_http.erl index f5eef71..8ebd42e 100644 --- a/src/gun_http.erl +++ b/src/gun_http.erl @@ -29,7 +29,8 @@ -type io() :: head | {body, non_neg_integer()} | body_close | body_chunked. --type websocket_info() :: {websocket, reference(), binary(), [binary()], [], gun:ws_opts()}. %% key, extensions, protocols, options +%% @todo Make that a record. +-type websocket_info() :: {websocket, reference(), binary(), [binary()], gun:ws_opts()}. %% key, extensions, options -record(stream, { ref :: reference() | websocket_info(), @@ -164,8 +165,8 @@ handle_head(Data, State=#http_state{owner=Owner, version=ClientVersion, {Version, Status, _, Rest} = cow_http:parse_status_line(Data), {Headers, Rest2} = cow_http:parse_headers(Rest), case {Status, StreamRef} of - {101, {websocket, _, WsKey, WsExtensions, WsProtocols, WsOpts}} -> - ws_handshake(Rest2, State, Headers, WsKey, WsExtensions, WsProtocols, WsOpts); + {101, {websocket, _, WsKey, WsExtensions, WsOpts}} -> + ws_handshake(Rest2, State, Headers, WsKey, WsExtensions, WsOpts); _ -> In = response_io_from_headers(Method, Version, Status, Headers), IsFin = case In of head -> fin; _ -> nofin end, @@ -174,7 +175,7 @@ handle_head(Data, State=#http_state{owner=Owner, version=ClientVersion, ok; true -> StreamRef2 = case StreamRef of - {websocket, SR, _, _, _, _} -> SR; + {websocket, SR, _, _, _} -> SR; _ -> StreamRef end, Owner ! {gun_response, self(), StreamRef2, @@ -330,7 +331,7 @@ cancel(State, StreamRef) -> %% HTTP does not provide any way to figure out what streams are unprocessed. down(#http_state{streams=Streams}) -> KilledStreams = [case Ref of - {websocket, Ref2, _, _, _, _} -> Ref2; + {websocket, Ref2, _, _, _} -> Ref2; _ -> Ref end || #stream{ref=Ref} <- Streams], {KilledStreams, []}. @@ -425,53 +426,59 @@ end_stream(State=#http_state{streams=[_|Tail]}) -> ws_upgrade(#http_state{version='HTTP/1.0'}, _, _, _, _, _, _) -> error; %% @todo ws_upgrade(State=#http_state{socket=Socket, transport=Transport, out=head}, - StreamRef, Host, Port, Path, Headers, WsOpts) -> + StreamRef, Host, Port, Path, Headers0, WsOpts) -> {Headers1, GunExtensions} = case maps:get(compress, WsOpts, false) of true -> {[{<<"sec-websocket-extensions">>, <<"permessage-deflate; client_max_window_bits; server_max_window_bits=15">>} - |Headers], + |Headers0], [<<"permessage-deflate">>]}; - false -> {Headers, []} + false -> {Headers0, []} + end, + Headers2 = case maps:get(protocols, WsOpts, []) of + [] -> Headers1; + ProtoOpt -> + << _, _, Proto/bits >> = iolist_to_binary([[<<", ">>, P] || {P, _} <- ProtoOpt]), + [{<<"sec-websocket-protocol">>, Proto}|Headers1] end, Key = cow_ws:key(), - Headers2 = [ + Headers3 = [ {<<"connection">>, <<"upgrade">>}, {<<"upgrade">>, <<"websocket">>}, {<<"sec-websocket-version">>, <<"13">>}, {<<"sec-websocket-key">>, Key} - |Headers1 + |Headers2 ], IsSecure = Transport:secure(), - Headers3 = case lists:keymember(<<"host">>, 1, Headers) of - true -> Headers2; - false when Port =:= 80, not IsSecure -> [{<<"host">>, Host}|Headers2]; - false when Port =:= 443, IsSecure -> [{<<"host">>, Host}|Headers2]; - false -> [{<<"host">>, [Host, $:, integer_to_binary(Port)]}|Headers2] + Headers = case lists:keymember(<<"host">>, 1, Headers0) of + true -> Headers3; + false when Port =:= 80, not IsSecure -> [{<<"host">>, Host}|Headers3]; + false when Port =:= 443, IsSecure -> [{<<"host">>, Host}|Headers3]; + false -> [{<<"host">>, [Host, $:, integer_to_binary(Port)]}|Headers3] end, - Transport:send(Socket, cow_http:request(<<"GET">>, Path, 'HTTP/1.1', Headers3)), + Transport:send(Socket, cow_http:request(<<"GET">>, Path, 'HTTP/1.1', Headers)), new_stream(State#http_state{connection=keepalive, out=head}, - {websocket, StreamRef, Key, GunExtensions, [], WsOpts}, <<"GET">>). + {websocket, StreamRef, Key, GunExtensions, WsOpts}, <<"GET">>). -ws_handshake(Buffer, State, Headers, Key, GunExtensions, GunProtocols, Opts) -> +ws_handshake(Buffer, State, Headers, Key, GunExtensions, Opts) -> %% @todo check upgrade, connection case lists:keyfind(<<"sec-websocket-accept">>, 1, Headers) of false -> close; {_, Accept} -> case cow_ws:encode_key(Key) of - Accept -> ws_handshake_extensions(Buffer, State, Headers, GunExtensions, GunProtocols, Opts); + Accept -> ws_handshake_extensions(Buffer, State, Headers, GunExtensions, Opts); _ -> close end end. -ws_handshake_extensions(Buffer, State, Headers, GunExtensions, GunProtocols, Opts) -> +ws_handshake_extensions(Buffer, State, Headers, GunExtensions, Opts) -> case lists:keyfind(<<"sec-websocket-extensions">>, 1, Headers) of false -> - ws_handshake_protocols(Buffer, State, Headers, #{}, GunProtocols); + ws_handshake_protocols(Buffer, State, Headers, #{}, Opts); {_, ExtHd} -> case ws_validate_extensions(cow_http_hd:parse_sec_websocket_extensions(ExtHd), GunExtensions, #{}, Opts) of close -> close; - Extensions -> ws_handshake_protocols(Buffer, State, Headers, Extensions, GunProtocols) + Extensions -> ws_handshake_protocols(Buffer, State, Headers, Extensions, Opts) end end. @@ -493,11 +500,23 @@ ws_validate_extensions(_, _, _, _) -> close. %% @todo Validate protocols. -ws_handshake_protocols(Buffer, State, Headers, Extensions, _GunProtocols = []) -> - Protocols = [], - ws_handshake_end(Buffer, State, Headers, Extensions, Protocols). +ws_handshake_protocols(Buffer, State, Headers, Extensions, Opts) -> + case lists:keyfind(<<"sec-websocket-protocol">>, 1, Headers) of + false -> + ws_handshake_end(Buffer, State, Headers, Extensions, + maps:get(default_protocol, Opts, gun_ws_handler), Opts); + {_, Proto} -> + ProtoOpt = maps:get(protocols, Opts, []), + case lists:keyfind(Proto, 1, ProtoOpt) of + {_, Handler} -> + ws_handshake_end(Buffer, State, Headers, Extensions, Handler, Opts); + false -> + close + end + end. -ws_handshake_end(Buffer, #http_state{owner=Owner, socket=Socket, transport=Transport}, Headers, Extensions, Protocols) -> +ws_handshake_end(Buffer, #http_state{owner=Owner, socket=Socket, transport=Transport}, + Headers, Extensions, Handler, Opts) -> %% Send ourselves the remaining buffer, if any. _ = case Buffer of <<>> -> @@ -506,4 +525,4 @@ ws_handshake_end(Buffer, #http_state{owner=Owner, socket=Socket, transport=Trans {OK, _, _} = Transport:messages(), self() ! {OK, Socket, Buffer} end, - gun_ws:init(Owner, Socket, Transport, Headers, Extensions, Protocols). + gun_ws:init(Owner, Socket, Transport, Headers, Extensions, Handler, Opts). -- cgit v1.2.3