cowboy的cookie和session的例子

session插件需要下载https://github.com/chvanikoff/cowboy_session

如果session需要分布式存储，可以参考https://github.com/spiegela/cowboy_session_storage_redis，他用的是redis，基于上面的cowboy_session做的扩展，我们如果有三方考虑的存储，完全可以自己实现分布式session处理。

创建工程

rebar-creator create-app testCowboy

testCowboy_app.erl

-module(testCowboy_app).-behaviour(application).-export([start/, stop/]).-define(C_ACCEPTORS,  ).start(_StartType, _StartArgs) ->
    application:start(crypto),
    application:start(cowlib),
    application:start(ranch),
    application:start(cowboy),    application:start(gproc),
    application:start(uuid),
    application:start(cowboy_session),
%%     如果使用redis存session，在这里添加这个
    cowboy_session_config:update_storage(cowboy_session_storage_redis),    Routes    = route_helper:get_routes(),
    Dispatch  = cowboy_router:compile(Routes),
    Port      = ,
    TransOpts = [{port, Port}],
    ProtoOpts = [{env, [{dispatch, Dispatch}]}],
    cowboy:start_http(http, ?C_ACCEPTORS, TransOpts, ProtoOpts).stop(_State) ->
    ok.

route_helper.erl

-module(route_helper).-export([get_routes/]).get_routes() ->
    [
        {'_', [
            {"/cookie_read", cookie_read_handler, []},
            {"/cookie_write", cookie_write_handler, []},
            {"/session_read", session_read_handler, []},
            {"/session_write", session_write_handler, []},
        ]}
    ].

cookie_read_handler.erl

-module(cookie_read_handler).-export([init/]).
-export([handle/]).
-export([terminate/]).init(_Transport, Req, []) ->
    {ok, Req, undefined}.handle(Req, State) ->
    {CookieVal,_} = cowboy_req:cookie(<<"test_cookie">>, Req,<<"no cookie found">>),
    {ok, Req2} = cowboy_req:reply(, [{<<"content-type">>, <<"text/html">>}],CookieVal, Req),
    {ok, Req2, State}.terminate(_Reason, _Req, _State) ->
    ok.

cookie_write_handler.erl

-module(cookie_write_handler).-export([init/]).
-export([handle/]).
-export([terminate/]).init(_Transport, Req, []) ->
    {ok, Req, undefined}.handle(Req, State) ->
    TestCookieVal = integer_to_list(random:uniform()),
    Req2 = cowboy_req:set_resp_cookie(<<"test_cookie">>, TestCookieVal, [{path, <<"/">>}], Req),
    {ok, Req3} = cowboy_req:reply(, [{<<"content-type">>, <<"text/html">>}],TestCookieVal, Req2),
    {ok, Req3, State}.terminate(_Reason, _Req, _State) ->
    ok.

session_read_handler.erl

-module(session_read_handler).-export([init/]).
-export([handle/]).
-export([terminate/]).init(_Transport, Req, []) ->
    {ok, Req, undefined}.handle(Req, State) ->
    {SessionVal, Req2} = cowboy_session:get(<<"test_session">>, <<"no session found">>,Req),
    {ok, Req3} = cowboy_req:reply(, [{<<"content-type">>, <<"text/html">>}],SessionVal, Req2),
    {ok, Req3, State}.terminate(_Reason, _Req, _State) ->
    ok.

session_write_handler.erl

-module(session_write_handler).-export([init/]).
-export([handle/]).
-export([terminate/]).init(_Transport, Req, []) ->
    {ok, Req, undefined}.handle(Req, State) ->
    TestCookieVal = integer_to_list(random:uniform()),
    {ok, Req2} = cowboy_session:set(<<"test_session">>, TestCookieVal, Req),
    {ok, Req3} = cowboy_req:reply(, [{<<"content-type">>, <<"text/html">>}],TestCookieVal, Req2),
    {ok, Req3, State}.terminate(_Reason, _Req, _State) ->
    ok.

如果测试session存redis，下载cowboy_session_storage_redis放工程编译即可。