直接贴代码，一切尽在不言中
%% cowboy的restful的文档，一定要好好阅读http://ninenines.eu/docs/en/cowboy/HEAD/manual/cowboy_rest/
%% 几大post提交方式https://imququ.com/post/four-ways-to-post-data-in-http.html
%% curl测试命令curl -l -H "Content-type:application/json" -X POST http://127.0.0.1:8080 -d "aaa=bbb"
-module(restful_handler). -export([init/]).
-export([allowed_methods/]).
-export([content_types_provided/]).
-export([content_types_accepted/]).
-export([delete_completed/]).
-export([delete_resource/]). -export([hello_to_html/]).
-export([form_urlencoded_post/]).
-export([form_data_post/]).
-export([json_post/]). init(Req, Opts) ->
{cowboy_rest, Req, Opts}. allowed_methods(Req, State) ->
Methods = [
<<"HEAD">>,
<<"GET">>,
<<"POST">>,
<<"PATCH">>,
<<"DELETE">>,
<<"OPTIONS">>
],
{Methods, Req, State}. content_types_provided(Req, State) ->
Handlers = [
{<<"text/html">>, hello_to_html}, {<<"application/x-www-form-urlencoded">>, form_urlencoded_post},
{<<"multipart/form-data">>, form_data_post},
{<<"application/json">>, json_post}
],
{Handlers, Req, State}. content_types_accepted(Req, State) ->
Handlers = [
{<<"application/x-www-form-urlencoded">>, form_urlencoded_post},
{<<"multipart/form-data">>, form_data_post},
{<<"application/json">>, json_post}
],
{Handlers, Req, State}. delete_completed(Req, State) ->
io:format("will delete resource~n"),
{true, Req, State}. delete_resource(Req, State) ->
io:format("delete resource finish~n"),
{true, Req, State}. hello_to_html(Req, State) ->
Body = <<"html">>,
{Body, Req, State}. form_urlencoded_post(Req, State) ->
{ok, PostVals, _Req2} = cowboy_req:body_qs(Req),
PostVal1 = proplists:get_value(<<"aaa">>, PostVals),
PostVal2 = proplists:get_value(<<"bbb">>, PostVals),
io:format("form_urlencoded_post~p~p~n",[PostVal1,PostVal2]), Body = string:concat(
erlang:bitstring_to_list(PostVal1),
erlang:bitstring_to_list(PostVal2)
),
NewReq = cowboy_req:set_resp_body(erlang:list_to_bitstring(Body),Req),
{true, NewReq, State}. form_data_post(Req, State) ->
{ok, PostVals, _Req2} = cowboy_req:body_qs(Req),
PostVal = proplists:get_value(<<"aaa">>, PostVals),
io:format("form_data_post~p~n",[PostVal]),
NewReq = cowboy_req:set_resp_body(PostVal,Req),
{true, NewReq, State}. json_post(Req, State) ->
{ok, PostVals, _Req2} = cowboy_req:body_qs(Req),
PostVal = proplists:get_value(<<"aaa">>, PostVals),
io:format("json_post~p~n",[PostVal]),
NewReq = cowboy_req:set_resp_body(PostVal,Req),
{true, NewReq, State}.