From 8164b504534e932df24adb65c5e15ed8d8a9feea Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= Date: Mon, 12 Nov 2018 18:12:44 +0100 Subject: Add deflate options for Websocket compression They allow the server to configure what it is willing to accept for both the negotiated configuration (takeover and window bits) and the other zlib options (level, mem_level and strategy). This can be used to reduce the memory and/or CPU footprint of the compressed data, which comes with a cost in compression ratio. --- src/cowboy_websocket.erl | 68 +++++++++++++++++++++++++----------------------- 1 file changed, 35 insertions(+), 33 deletions(-) (limited to 'src') diff --git a/src/cowboy_websocket.erl b/src/cowboy_websocket.erl index 913c116..e1cb2d4 100644 --- a/src/cowboy_websocket.erl +++ b/src/cowboy_websocket.erl @@ -66,6 +66,7 @@ -type opts() :: #{ compress => boolean(), + deflate_opts => cow_ws:deflate_opts(), idle_timeout => timeout(), max_frame_size => non_neg_integer() | infinity, req_filter => fun((cowboy_req:req()) -> map()) @@ -77,13 +78,11 @@ ref :: ranch:ref(), socket = undefined :: inet:socket() | {pid(), cowboy_stream:streamid()} | undefined, transport = undefined :: module() | undefined, + opts = #{} :: opts(), active = true :: boolean(), handler :: module(), key = undefined :: undefined | binary(), - timeout = infinity :: timeout(), timeout_ref = undefined :: undefined | reference(), - compress = false :: boolean(), - max_frame_size :: non_neg_integer() | infinity, messages = undefined :: undefined | {atom(), atom(), atom()}, hibernate = false :: boolean(), frag_state = undefined :: cow_ws:frag_state(), @@ -125,15 +124,11 @@ upgrade(Req, Env, Handler, HandlerState) -> when Req::cowboy_req:req(), Env::cowboy_middleware:env(). %% @todo Immediately crash if a response has already been sent. upgrade(Req0=#{version := Version}, Env, Handler, HandlerState, Opts) -> - Timeout = maps:get(idle_timeout, Opts, 60000), - MaxFrameSize = maps:get(max_frame_size, Opts, infinity), - Compress = maps:get(compress, Opts, false), FilteredReq = case maps:get(req_filter, Opts, undefined) of undefined -> maps:with([method, version, scheme, host, port, path, qs, peer], Req0); FilterFun -> FilterFun(Req0) end, - State0 = #state{handler=Handler, timeout=Timeout, compress=Compress, - max_frame_size=MaxFrameSize, req=FilteredReq}, + State0 = #state{opts=Opts, handler=Handler, req=FilteredReq}, try websocket_upgrade(State0, Req0) of {ok, State, Req} -> websocket_handshake(State, Req, HandlerState, Env); @@ -174,13 +169,14 @@ websocket_version(State, Req) -> end, websocket_extensions(State, Req#{websocket_version => WsVersion}). -websocket_extensions(State=#state{compress=Compress}, Req) -> +websocket_extensions(State=#state{opts=Opts}, Req) -> %% @todo We want different options for this. For example %% * compress everything auto %% * compress only text auto %% * compress only binary auto %% * compress nothing auto (but still enabled it) %% * disable compression + Compress = maps:get(compress, Opts, false), case {Compress, cowboy_req:parse_header(<<"sec-websocket-extensions">>, Req)} of {true, Extensions} when Extensions =/= undefined -> websocket_extensions(State, Req, Extensions, []); @@ -193,15 +189,15 @@ websocket_extensions(State, Req, [], []) -> websocket_extensions(State, Req, [], [<<", ">>|RespHeader]) -> {ok, State, cowboy_req:set_resp_header(<<"sec-websocket-extensions">>, lists:reverse(RespHeader), Req)}; %% For HTTP/2 we ARE on the controlling process and do NOT want to update the owner. -websocket_extensions(State=#state{extensions=Extensions}, Req=#{pid := Pid, version := Version}, +websocket_extensions(State=#state{opts=Opts, extensions=Extensions}, + Req=#{pid := Pid, version := Version}, [{<<"permessage-deflate">>, Params}|Tail], RespHeader) -> - %% @todo Make deflate options configurable. - Opts0 = #{level => best_compression, mem_level => 8, strategy => default}, - Opts = case Version of - 'HTTP/1.1' -> Opts0#{owner => Pid}; - _ -> Opts0 + DeflateOpts0 = maps:get(deflate_opts, Opts, #{}), + DeflateOpts = case Version of + 'HTTP/1.1' -> DeflateOpts0#{owner => Pid}; + _ -> DeflateOpts0 end, - try cow_ws:negotiate_permessage_deflate(Params, Extensions, Opts) of + try cow_ws:negotiate_permessage_deflate(Params, Extensions, DeflateOpts) of {ok, RespExt, Extensions2} -> websocket_extensions(State#state{extensions=Extensions2}, Req, Tail, [<<", ">>, RespExt|RespHeader]); @@ -210,15 +206,15 @@ websocket_extensions(State=#state{extensions=Extensions}, Req=#{pid := Pid, vers catch exit:{error, incompatible_zlib_version, _} -> websocket_extensions(State, Req, Tail, RespHeader) end; -websocket_extensions(State=#state{extensions=Extensions}, Req=#{pid := Pid, version := Version}, +websocket_extensions(State=#state{opts=Opts, extensions=Extensions}, + Req=#{pid := Pid, version := Version}, [{<<"x-webkit-deflate-frame">>, Params}|Tail], RespHeader) -> - %% @todo Make deflate options configurable. - Opts0 = #{level => best_compression, mem_level => 8, strategy => default}, - Opts = case Version of - 'HTTP/1.1' -> Opts0#{owner => Pid}; - _ -> Opts0 + DeflateOpts0 = maps:get(deflate_opts, Opts, #{}), + DeflateOpts = case Version of + 'HTTP/1.1' -> DeflateOpts0#{owner => Pid}; + _ -> DeflateOpts0 end, - try cow_ws:negotiate_x_webkit_deflate_frame(Params, Extensions, Opts) of + try cow_ws:negotiate_x_webkit_deflate_frame(Params, Extensions, DeflateOpts) of {ok, RespExt, Extensions2} -> websocket_extensions(State#state{extensions=Extensions2}, Req, Tail, [<<", ">>, RespExt|RespHeader]); @@ -317,13 +313,18 @@ before_loop(State=#state{socket=Socket, transport=Transport}, loop(State, HandlerState, ParseState). -spec loop_timeout(#state{}) -> #state{}. -loop_timeout(State=#state{timeout=infinity}) -> - State#state{timeout_ref=undefined}; -loop_timeout(State=#state{timeout=Timeout, timeout_ref=PrevRef}) -> - _ = case PrevRef of undefined -> ignore; PrevRef -> - erlang:cancel_timer(PrevRef) end, - TRef = erlang:start_timer(Timeout, self(), ?MODULE), - State#state{timeout_ref=TRef}. +loop_timeout(State=#state{opts=Opts, timeout_ref=PrevRef}) -> + _ = case PrevRef of + undefined -> ignore; + PrevRef -> erlang:cancel_timer(PrevRef) + end, + case maps:get(idle_timeout, Opts, 60000) of + infinity -> + State#state{timeout_ref=undefined}; + Timeout -> + TRef = erlang:start_timer(Timeout, self(), ?MODULE), + State#state{timeout_ref=TRef} + end. -spec loop(#state{}, any(), parse_state()) -> no_return(). loop(State=#state{parent=Parent, socket=Socket, messages=Messages, @@ -377,9 +378,9 @@ parse(State, HandlerState, PS=#ps_payload{buffer=Buffer}, Data) -> parse_payload(State, HandlerState, PS#ps_payload{buffer= <<>>}, <>). -parse_header(State=#state{max_frame_size=MaxFrameSize, - frag_state=FragState, extensions=Extensions}, +parse_header(State=#state{opts=Opts, frag_state=FragState, extensions=Extensions}, HandlerState, ParseState=#ps_header{buffer=Data}) -> + MaxFrameSize = maps:get(max_frame_size, Opts, infinity), case cow_ws:parse_header(Data, Extensions, FragState) of %% All frames sent from the client to the server are masked. {_, _, _, _, undefined, _} -> @@ -423,10 +424,11 @@ parse_payload(State=#state{frag_state=FragState, utf8_state=Incomplete, extensio websocket_close(State, HandlerState, Error) end. -dispatch_frame(State=#state{max_frame_size=MaxFrameSize, frag_state=FragState, +dispatch_frame(State=#state{opts=Opts, frag_state=FragState, frag_buffer=SoFar, extensions=Extensions}, HandlerState, #ps_payload{type=Type0, unmasked=Payload0, close_code=CloseCode0}, RemainingData) -> + MaxFrameSize = maps:get(max_frame_size, Opts, infinity), case cow_ws:make_frame(Type0, Payload0, CloseCode0, FragState) of %% @todo Allow receiving fragments. {fragment, _, _, Payload} when byte_size(Payload) + byte_size(SoFar) > MaxFrameSize -> -- cgit v1.2.3