diff options
Diffstat (limited to 'src/cowboy_stream_h.erl')
| -rw-r--r-- | src/cowboy_stream_h.erl | 66 |
1 files changed, 61 insertions, 5 deletions
diff --git a/src/cowboy_stream_h.erl b/src/cowboy_stream_h.erl index f924e28..b834c17 100644 --- a/src/cowboy_stream_h.erl +++ b/src/cowboy_stream_h.erl @@ -21,10 +21,12 @@ -export([info/3]). -export([terminate/3]). +-export([proc_lib_hack/3]). -export([execute/3]). -export([resume/5]). -record(state, { + ref = undefined :: ranch:ref(), pid = undefined :: pid(), read_body_ref = undefined :: reference(), read_body_length = 0 :: non_neg_integer(), @@ -38,12 +40,12 @@ %% @todo proper specs -spec init(_,_,_) -> _. -init(_StreamID, Req, Opts) -> +init(_StreamID, Req=#{ref := Ref}, Opts) -> Env = maps:get(env, Opts, #{}), Middlewares = maps:get(middlewares, Opts, [cowboy_router, cowboy_handler]), Shutdown = maps:get(shutdown, Opts, 5000), - Pid = proc_lib:spawn_link(?MODULE, execute, [Req, Env, Middlewares]), - {[{spawn, Pid, Shutdown}], #state{pid=Pid}}. + Pid = proc_lib:spawn_link(?MODULE, proc_lib_hack, [Req, Env, Middlewares]), + {[{spawn, Pid, Shutdown}], #state{ref=Ref, pid=Pid}}. %% If we receive data and stream is waiting for data: %% If we accumulated enough data or IsFin=fin, send it. @@ -64,8 +66,29 @@ data(_StreamID, IsFin, Data, State=#state{pid=Pid, read_body_ref=Ref, read_body_ -spec info(_,_,_) -> _. info(_StreamID, {'EXIT', Pid, normal}, State=#state{pid=Pid}) -> {[stop], State}; -info(_StreamID, Reason = {'EXIT', Pid, _}, State=#state{pid=Pid}) -> - {[{internal_error, Reason, 'Stream process crashed.'}], State}; +%% @todo Transition. +%% In the future it would be better to simplify things +%% and only catch this at the stream level. +%% +%% Maybe we don't need specific error messages +%% for every single callbacks anymore? +info(_StreamID, Exit = {'EXIT', Pid, {cowboy_handler, _}}, State=#state{pid=Pid}) -> + %% No crash report; one has already been sent. + {[ + {response, 500, #{<<"content-length">> => <<"0">>}, <<>>}, + {internal_error, Exit, 'Stream process crashed.'} + ], State}; +info(_StreamID, {'EXIT', Pid, {_Reason, [_, {cow_http_hd, _, _, _}|_]}}, State=#state{pid=Pid}) -> + %% @todo Have an option to enable/disable this specific crash report? + %%report_crash(Ref, StreamID, Pid, Reason, Stacktrace), + %% @todo Headers? Details in body? More stuff in debug only? + {[{response, 400, #{}, <<>>}, stop], State}; +info(StreamID, Exit = {'EXIT', Pid, {Reason, Stacktrace}}, State=#state{ref=Ref, pid=Pid}) -> + report_crash(Ref, StreamID, Pid, Reason, Stacktrace), + {[ + {response, 500, #{<<"content-length">> => <<"0">>}, <<>>}, + {internal_error, Exit, 'Stream process crashed.'} + ], State}; %% Request body, no body buffer but IsFin=fin. info(_StreamID, {read_body, Ref, _}, State=#state{pid=Pid, read_body_is_fin=fin, read_body_buffer= <<>>}) -> Pid ! {request_body, Ref, fin, <<>>}, @@ -89,6 +112,7 @@ info(_StreamID, SwitchProtocol = {switch_protocol, _, _, _}, State) -> {[SwitchProtocol], State}; %% Stray message. info(_StreamID, _Msg, State) -> + %% @todo Error report. %% @todo Cleanup if no reply was sent when stream ends. {[], State}. @@ -97,8 +121,40 @@ info(_StreamID, _Msg, State) -> terminate(_StreamID, _Reason, _State) -> ok. +%% We use ~999999p here instead of ~w because the latter doesn't +%% support printable strings. +report_crash(_, _, _, normal, _) -> + ok; +report_crash(_, _, _, shutdown, _) -> + ok; +report_crash(_, _, _, {shutdown, _}, _) -> + ok; +report_crash(Ref, StreamID, Pid, Reason, Stacktrace) -> + error_logger:error_msg( + "Ranch listener ~p, connection process ~p, stream ~p " + "had its request process ~p exit with reason " + "~999999p and stacktrace ~999999p~n", + [Ref, self(), StreamID, Pid, Reason, Stacktrace]). + %% Request process. +%% This hack is necessary because proc_lib does not propagate +%% stacktraces by default. This is ugly because we end up +%% having two try/catch instead of one (the one in proc_lib), +%% just to add the stacktrace information. +%% +%% @todo Remove whenever proc_lib propagates stacktraces. +-spec proc_lib_hack(_, _, _) -> _. +proc_lib_hack(Req, Env, Middlewares) -> + try + execute(Req, Env, Middlewares) + catch + _:Reason when element(1, Reason) =:= cowboy_handler -> + exit(Reason); + _:Reason -> + exit({Reason, erlang:get_stacktrace()}) + end. + %% @todo %-spec execute(cowboy_req:req(), #state{}, cowboy_middleware:env(), [module()]) % -> ok. |