From a45813c60f0f983a24ea29d491b37f0590fdd087 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= <essen@ninenines.eu>
Date: Sat, 18 Feb 2017 18:26:20 +0100
Subject: 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.
---
 doc/src/manual/cowboy_rest.asciidoc | 3 ---
 1 file changed, 3 deletions(-)

(limited to 'doc/src/manual/cowboy_rest.asciidoc')

diff --git a/doc/src/manual/cowboy_rest.asciidoc b/doc/src/manual/cowboy_rest.asciidoc
index 26515fb..73adb23 100644
--- a/doc/src/manual/cowboy_rest.asciidoc
+++ b/doc/src/manual/cowboy_rest.asciidoc
@@ -21,9 +21,6 @@ REST handlers implement the following interface:
 ----
 init(Req, State)
     -> {cowboy_rest, Req, State}
-     | {cowboy_rest, Req, State, hibernate}
-     | {cowboy_rest, Req, State, timeout()}
-     | {cowboy_rest, Req, State, timeout(), hibernate}
 
 Callback(Req, State)
     -> {Result, Req, State}
-- 
cgit v1.2.3

