path: root/src/cowboy_handler.erl
diff options
authorLoïc Hoguin <[email protected]>2017-02-18 18:26:20 +0100
committerLoïc Hoguin <[email protected]>2017-02-18 18:26:20 +0100
commita45813c60f0f983a24ea29d491b37f0590fdd087 (patch)
treec7e741ac4a684b365e70f7ff73d0c4b6e34232a7 /src/cowboy_handler.erl
parent80f8cda7ff8fe6a575b4c2eaedd8451acf4fcef3 (diff)
Allow passing options to sub protocols
Before this commit we had an issue where configuring a Websocket connection was simply not possible without doing magic, adding callbacks or extra return values. The init/2 function only allowed setting hibernate and timeout options. After this commit, when switching to a different type of handler you can either return {module, Req, State} or {module, Req, State, Opts} where Opts is any value (as far as the sub protocol interface is concerned) and is ultimately checked by the custom handlers. A large protocol like Websocket would accept only a map there, with many different options, while a small interface like loop handlers would allow passing hibernate and nothing else. For Websocket, hibernate must be set from the websocket_init/1 callback, because init/2 executes in a separate process. Sub protocols now have two callbacks: one with the Opts value, one without. The loop handler code was largely reworked and simplified. It does not need to manage a timeout or read from the socket anymore, it's the job of the protocol code. A lot of unnecessary stuff was therefore removed. Websocket compression must now be enabled from the handler options instead of per listener. This means that a project can have two separate Websocket handlers with different options. Compression is still disabled by default, and the idle_timeout value was changed from inifnity to 60000 (60 seconds), as that's safer and is also a good value for mobile devices.
Diffstat (limited to 'src/cowboy_handler.erl')
1 files changed, 4 insertions, 10 deletions
diff --git a/src/cowboy_handler.erl b/src/cowboy_handler.erl
index 61c1b6a..3249f76 100644
--- a/src/cowboy_handler.erl
+++ b/src/cowboy_handler.erl
@@ -25,9 +25,7 @@
-callback init(Req, any())
-> {ok | module(), Req, any()}
- | {module(), Req, any(), hibernate}
- | {module(), Req, any(), timeout()}
- | {module(), Req, any(), timeout(), hibernate}
+ | {module(), Req, any(), any()}
when Req::cowboy_req:req().
-callback terminate(any(), cowboy_req:req(), any()) -> ok.
@@ -41,13 +39,9 @@ execute(Req, Env=#{handler := Handler, handler_opts := HandlerOpts}) ->
Result = terminate(normal, Req2, State, Handler),
{ok, Req2, Env#{result => Result}};
{Mod, Req2, State} ->
- Mod:upgrade(Req2, Env, Handler, State, infinity, run);
- {Mod, Req2, State, hibernate} ->
- Mod:upgrade(Req2, Env, Handler, State, infinity, hibernate);
- {Mod, Req2, State, Timeout} ->
- Mod:upgrade(Req2, Env, Handler, State, Timeout, run);
- {Mod, Req2, State, Timeout, hibernate} ->
- Mod:upgrade(Req2, Env, Handler, State, Timeout, hibernate)
+ Mod:upgrade(Req2, Env, Handler, State);
+ {Mod, Req2, State, Opts} ->
+ Mod:upgrade(Req2, Env, Handler, State, Opts)
catch Class:Reason ->
terminate({crash, Class, Reason}, Req, HandlerOpts, Handler),
erlang:raise(Class, Reason, erlang:get_stacktrace())