From 1b3f510b7e8d5413901ba72adfe361773f3e9097 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= Date: Thu, 3 Jan 2013 22:47:51 +0100 Subject: Add middleware support Middlewares allow customizing the request processing. All existing Cowboy project are incompatible with this commit. You need to change `{dispatch, Dispatch}` in the protocol options to `{env, [{dispatch, Dispatch}]}` to fix your code. --- src/cowboy_middleware.erl | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 src/cowboy_middleware.erl (limited to 'src/cowboy_middleware.erl') diff --git a/src/cowboy_middleware.erl b/src/cowboy_middleware.erl new file mode 100644 index 0000000..0c1ca77 --- /dev/null +++ b/src/cowboy_middleware.erl @@ -0,0 +1,36 @@ +%% Copyright (c) 2013, Loïc Hoguin +%% +%% Permission to use, copy, modify, and/or distribute this software for any +%% purpose with or without fee is hereby granted, provided that the above +%% copyright notice and this permission notice appear in all copies. +%% +%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR +%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF +%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + +%% @doc Behaviour for middlewares. +%% +%% Only one function needs to be implemented, execute/2. +%% It receives the Req and the environment and returns them +%% optionally modified. It can decide to stop the processing with +%% or without an error. It is also possible to hibernate the process +%% if needed. +%% +%% A middleware can perform any operation. Make sure you always return +%% the last modified Req so that Cowboy has the up to date information +%% about the request. +-module(cowboy_middleware). + +-type env() :: [{atom(), any()}]. +-export_type([env/0]). + +-callback execute(Req, Env) + -> {ok, Req, Env} + | {suspend, module(), atom(), any()} + | {halt, Req} + | {error, cowboy_http:status(), Req} + when Req::cowboy_req:req(), Env::env(). -- cgit v1.2.3