From 88414e36b4199f10ed5b29d5fffda037c5d81eca Mon Sep 17 00:00:00 2001 From: Adam Cammack Date: Fri, 1 Mar 2013 18:02:33 -0600 Subject: Add an example of onresponse hooks Also fix the guide entry on hooks. --- examples/README.md | 3 +++ examples/error_hook/README.md | 30 ++++++++++++++++++++++++ examples/error_hook/rebar.config | 4 ++++ examples/error_hook/src/error_hook.app.src | 15 ++++++++++++ examples/error_hook/src/error_hook.erl | 14 +++++++++++ examples/error_hook/src/error_hook_app.erl | 24 +++++++++++++++++++ examples/error_hook/src/error_hook_responder.erl | 21 +++++++++++++++++ examples/error_hook/src/error_hook_sup.erl | 23 ++++++++++++++++++ examples/error_hook/start.sh | 3 +++ 9 files changed, 137 insertions(+) create mode 100644 examples/error_hook/README.md create mode 100644 examples/error_hook/rebar.config create mode 100644 examples/error_hook/src/error_hook.app.src create mode 100644 examples/error_hook/src/error_hook.erl create mode 100644 examples/error_hook/src/error_hook_app.erl create mode 100644 examples/error_hook/src/error_hook_responder.erl create mode 100644 examples/error_hook/src/error_hook_sup.erl create mode 100755 examples/error_hook/start.sh (limited to 'examples') diff --git a/examples/README.md b/examples/README.md index bda8e46..0e20d5f 100644 --- a/examples/README.md +++ b/examples/README.md @@ -22,6 +22,9 @@ Cowboy Examples * [elixir_hello_world](./elixir_hello_world): simplest example application with Elixir + * [error_hook](./error_hook): + provide custom error pages + * [eventsource](./eventsource): eventsource emitter and consumer diff --git a/examples/error_hook/README.md b/examples/error_hook/README.md new file mode 100644 index 0000000..4a0a4a6 --- /dev/null +++ b/examples/error_hook/README.md @@ -0,0 +1,30 @@ +Cowboy Error Hook +================= + +To compile this example you need rebar in your PATH. + +Type the following command: +``` +$ rebar get-deps compile +``` + +You can then start the Erlang node with the following command: +``` +./start.sh +``` + +Then point your browser to the indicated URL. + +Example +------- + +``` bash +$ curl -i http://localhost:8080 +HTTP/1.1 404 Not Found +connection: keep-alive +server: Cowboy +date: Wed, 27 Feb 2013 23:32:55 GMT +content-length: 56 + +404 Not Found: "/" is not the path you are looking for. +``` diff --git a/examples/error_hook/rebar.config b/examples/error_hook/rebar.config new file mode 100644 index 0000000..6ad3062 --- /dev/null +++ b/examples/error_hook/rebar.config @@ -0,0 +1,4 @@ +{deps, [ + {cowboy, ".*", + {git, "git://github.com/extend/cowboy.git", "master"}} +]}. diff --git a/examples/error_hook/src/error_hook.app.src b/examples/error_hook/src/error_hook.app.src new file mode 100644 index 0000000..80a1f2b --- /dev/null +++ b/examples/error_hook/src/error_hook.app.src @@ -0,0 +1,15 @@ +%% Feel free to use, reuse and abuse the code in this file. + +{application, error_hook, [ + {description, "Cowboy error handler example."}, + {vsn, "1"}, + {modules, []}, + {registered, []}, + {applications, [ + kernel, + stdlib, + cowboy + ]}, + {mod, {error_hook_app, []}}, + {env, []} +]}. diff --git a/examples/error_hook/src/error_hook.erl b/examples/error_hook/src/error_hook.erl new file mode 100644 index 0000000..3543590 --- /dev/null +++ b/examples/error_hook/src/error_hook.erl @@ -0,0 +1,14 @@ +%% Feel free to use, reuse and abuse the code in this file. + +-module(error_hook). + +%% API. +-export([start/0]). + +%% API. + +start() -> + ok = application:start(crypto), + ok = application:start(ranch), + ok = application:start(cowboy), + ok = application:start(error_hook). diff --git a/examples/error_hook/src/error_hook_app.erl b/examples/error_hook/src/error_hook_app.erl new file mode 100644 index 0000000..213eccf --- /dev/null +++ b/examples/error_hook/src/error_hook_app.erl @@ -0,0 +1,24 @@ +%% Feel free to use, reuse and abuse the code in this file. + +%% @private +-module(error_hook_app). +-behaviour(application). + +%% API. +-export([start/2]). +-export([stop/1]). + +%% API. + +start(_Type, _Args) -> + Dispatch = cowboy_router:compile([ + {'_', []} + ]), + {ok, _} = cowboy:start_http(http, 100, [{port, 8080}], [ + {env, [{dispatch, Dispatch}]}, + {onresponse, fun error_hook_responder:respond/4} + ]), + error_hook_sup:start_link(). + +stop(_State) -> + ok. diff --git a/examples/error_hook/src/error_hook_responder.erl b/examples/error_hook/src/error_hook_responder.erl new file mode 100644 index 0000000..31f2d5b --- /dev/null +++ b/examples/error_hook/src/error_hook_responder.erl @@ -0,0 +1,21 @@ +%% Feel free to use, reuse and abuse the code in this file. + +-module(error_hook_responder). + +-export([respond/4]). + +respond(404, Headers, <<>>, Req) -> + {Path, Req2} = cowboy_req:path(Req), + Body = <<"404 Not Found: \"", Path/binary, "\" is not the path you are looking for.\n">>, + Headers2 = lists:keyreplace(<<"content-length">>, 1, Headers, + {<<"content-length">>, integer_to_list(byte_size(Body))}), + {ok, Req3} = cowboy_req:reply(404, Headers2, Body, Req2), + Req3; +respond(Code, Headers, <<>>, Req) when is_integer(Code), Code >= 400 -> + Body = ["HTTP Error ", integer_to_list(Code), $\n], + Headers2 = lists:keyreplace(<<"content-length">>, 1, Headers, + {<<"content-length">>, integer_to_list(iolist_size(Body))}), + {ok, Req2} = cowboy_req:reply(Code, Headers2, Body, Req), + Req2; +respond(_Code, _Headers, _Body, Req) -> + Req. diff --git a/examples/error_hook/src/error_hook_sup.erl b/examples/error_hook/src/error_hook_sup.erl new file mode 100644 index 0000000..f92c156 --- /dev/null +++ b/examples/error_hook/src/error_hook_sup.erl @@ -0,0 +1,23 @@ +%% Feel free to use, reuse and abuse the code in this file. + +%% @private +-module(error_hook_sup). +-behaviour(supervisor). + +%% API. +-export([start_link/0]). + +%% supervisor. +-export([init/1]). + +%% API. + +-spec start_link() -> {ok, pid()}. +start_link() -> + supervisor:start_link({local, ?MODULE}, ?MODULE, []). + +%% supervisor. + +init([]) -> + Procs = [], + {ok, {{one_for_one, 10, 10}, Procs}}. diff --git a/examples/error_hook/start.sh b/examples/error_hook/start.sh new file mode 100755 index 0000000..ea40eb3 --- /dev/null +++ b/examples/error_hook/start.sh @@ -0,0 +1,3 @@ +#!/bin/sh +erl -pa ebin deps/*/ebin -s error_hook \ + -eval "io:format(\"Point your browser at http://localhost:8080~n\")." -- cgit v1.2.3