-<\/span>module<\/span>(<\/span>web_server<\/span>).<\/span>\n\n-<\/span>behaviour<\/span>(<\/span>gen_server<\/span>).<\/span>\n\n-<\/span>define<\/span>(<\/span>SERVER<\/span>,<\/span> ?MODULE<\/span>).<\/span>\n-<\/span>define<\/span>(<\/span>OK<\/span>,<\/span> <<<\/span>"ok"<\/span>>><\/span>).<\/span>\n\n%% API<\/span>\n-<\/span>export<\/span>([<\/span>start_link<\/span>/<\/span>1<\/span>,<\/span> dispatch_requests<\/span>/<\/span>1<\/span>,<\/span> stop<\/span>/<\/span>0<\/span>]).<\/span>\n\n%% gen_server callbacks<\/span>\n%% (Same old, same old. You can skip down to the handle/2 function...)<\/span>\n-<\/span>export<\/span>([<\/span>init<\/span>/<\/span>1<\/span>,<\/span> handle_call<\/span>/<\/span>3<\/span>,<\/span> handle_cast<\/span>/<\/span>2<\/span>,<\/span> handle_info<\/span>/<\/span>2<\/span>,<\/span>\n    terminate<\/span>/<\/span>2<\/span>,<\/span> code_change<\/span>/<\/span>3<\/span>]).<\/span>\n\nstart_link<\/span>(<\/span>Port<\/span>)<\/span> -><\/span>\n    gen_server<\/span>:<\/span>start_link<\/span>({<\/span>local<\/span>,<\/span> ?SERVER<\/span>},<\/span> ?MODULE<\/span>,<\/span> [<\/span>Port<\/span>],<\/span> []).<\/span>\n\ninit<\/span>([<\/span>Port<\/span>])<\/span> -><\/span>\n    mochiweb_http<\/span>:<\/span>start<\/span>(<\/span>\n        [{<\/span>port<\/span>,<\/span> Port<\/span>},<\/span>\n         {<\/span>loop<\/span>,<\/span> fun<\/span>(<\/span>Req<\/span>)<\/span> -><\/span> dispatch_requests<\/span>(<\/span>Req<\/span>)<\/span> end<\/span>}]),<\/span>\n    erlang<\/span>:<\/span>monitor<\/span>(<\/span>process<\/span>,<\/span> mochiweb_http<\/span>),<\/span>\n    {<\/span>ok<\/span>,<\/span> []}.<\/span>\n\nstop<\/span>()<\/span> -><\/span>\n    gen_server<\/span>:<\/span>cast<\/span>(<\/span>?SERVER<\/span>,<\/span> stop<\/span>).<\/span>\n\ndispatch_requests<\/span>(<\/span>Req<\/span>)<\/span> -><\/span>\n    Path<\/span> =<\/span> Req<\/span>:<\/span>get<\/span>(<\/span>path<\/span>),<\/span>\n    Action<\/span> =<\/span> clean_path<\/span>(<\/span>Path<\/span>),<\/span>\n    handle<\/span>(<\/span>Action<\/span>,<\/span> Req<\/span>).<\/span>\n\nhandle_call<\/span>(_<\/span>Request<\/span>,<\/span> _<\/span>From<\/span>,<\/span> State<\/span>)<\/span> -><\/span>\n    Reply<\/span> =<\/span> ok<\/span>,<\/span>\n    {<\/span>reply<\/span>,<\/span> Reply<\/span>,<\/span> State<\/span>}.<\/span>\n\nhandle_cast<\/span>(<\/span>stop<\/span>,<\/span> State<\/span>)<\/span> -><\/span>\n    {<\/span>stop<\/span>,<\/span> normal<\/span>,<\/span> State<\/span>};<\/span>\n\nhandle_cast<\/span>(_<\/span>Msg<\/span>,<\/span> State<\/span>)<\/span> -><\/span>\n    {<\/span>noreply<\/span>,<\/span> State<\/span>}.<\/span>\n\nhandle_info<\/span>({<\/span>'DOWN'<\/span>,<\/span> _,<\/span> _,<\/span> {<\/span>mochiweb_http<\/span>,<\/span> _},<\/span> _},<\/span> State<\/span>)<\/span> -><\/span>\n    {<\/span>stop<\/span>,<\/span> normal<\/span>,<\/span> State<\/span>};<\/span>\n\nhandle_info<\/span>(_<\/span>Info<\/span>,<\/span> State<\/span>)<\/span> -><\/span>\n    {<\/span>noreply<\/span>,<\/span> State<\/span>}.<\/span>\n\nterminate<\/span>(_<\/span>Reason<\/span>,<\/span> _<\/span>State<\/span>)<\/span> -><\/span>\n    mochiweb_http<\/span>:<\/span>stop<\/span>(),<\/span>\n    ok<\/span>.<\/span>\n\ncode_change<\/span>(_<\/span>OldVsn<\/span>,<\/span> State<\/span>,<\/span> _<\/span>Extra<\/span>)<\/span> -><\/span>\n    {<\/span>ok<\/span>,<\/span> State<\/span>}.<\/span>\n\n\n%% This was ripped off from the following blog:<\/span>\n%% http://willcodeforfoo.com/2009/07/29/using-mochiweb-to-create-a-webframework-in-erlang/<\/span>\n\nhandle<\/span>(<\/span>Path<\/span>,<\/span> Req<\/span>)<\/span> -><\/span>\n    CleanPath<\/span> =<\/span> clean_path<\/span>(<\/span>Path<\/span>),<\/span>\n    CAtom<\/span> =<\/span> erlang<\/span>:<\/span>list_to_atom<\/span>(<\/span>top_level_request<\/span>(<\/span>CleanPath<\/span>)),<\/span>    \n    ControllerPath<\/span> =<\/span> parse_controller_path<\/span>(<\/span>CleanPath<\/span>),<\/span>\n    case<\/span> CAtom<\/span> of<\/span>\n        home<\/span> -><\/span> \n            IndexContents<\/span> =<\/span> case<\/span> file<\/span>:<\/span>read_file<\/span>(<\/span>"www/index.html"<\/span>)<\/span> of<\/span>\n                {<\/span>ok<\/span>,<\/span> Contents<\/span>}<\/span> -><\/span> \n                    Contents<\/span>;<\/span>\n                _<\/span> -><\/span> \n                    "<html><head><title>Error</title></head><body><h1>Uh oh</h1></body></html>"<\/span>\n            end<\/span>,<\/span>\n            Req<\/span>:<\/span>ok<\/span>({<\/span>"text/html"<\/span>,<\/span> IndexContents<\/span>});<\/span>\n        assets<\/span> -><\/span> \n            Req<\/span>:<\/span>ok<\/span>(<\/span>assets<\/span>:<\/span>get<\/span>(<\/span>ControllerPath<\/span>));<\/span>\n        ControllerAtom<\/span> -><\/span>\n            Body<\/span> =<\/span> case<\/span> Req<\/span>:<\/span>get<\/span>(<\/span>method<\/span>)<\/span> of<\/span>\n                'GET'<\/span> -><\/span> ControllerAtom<\/span>:<\/span>get<\/span>(<\/span>ControllerPath<\/span>);<\/span>\n                'POST'<\/span> -><\/span> ControllerAtom<\/span>:<\/span>post<\/span>(<\/span>ControllerPath<\/span>,<\/span> decode_data_from_request<\/span>(<\/span>Req<\/span>));<\/span>\n                'PUT'<\/span> -><\/span> ControllerAtom<\/span>:<\/span>put<\/span>(<\/span>ControllerPath<\/span>,<\/span> decode_data_from_request<\/span>(<\/span>Req<\/span>));<\/span>\n                'DELETE'<\/span> -><\/span> ControllerAtom<\/span>:<\/span>delete<\/span>(<\/span>ControllerPath<\/span>,<\/span> decode_data_from_request<\/span>(<\/span>Req<\/span>));<\/span>\n                Other<\/span> -><\/span> subst<\/span>(<\/span>"Other <\/span>~p<\/span> on: <\/span>~s~n<\/span>"<\/span>,<\/span> [<\/span>users<\/span>,<\/span> Other<\/span>])<\/span>\n            end<\/span>,<\/span>\n            Req<\/span>:<\/span>ok<\/span>({<\/span>"text/html"<\/span>,<\/span> Body<\/span>})<\/span>\n    end<\/span>.<\/span>\n\n%% Helper methods:<\/span>\n\n%% Parse the request body as JSON<\/span>\ndecode_data_from_request<\/span>(<\/span>Req<\/span>)<\/span> -><\/span>\n    RecvBody<\/span> =<\/span> Req<\/span>:<\/span>recv_body<\/span>(),<\/span>\n    Data<\/span> =<\/span> case<\/span> RecvBody<\/span> of<\/span>\n        <<>><\/span> -><\/span> \n            erlang<\/span>:<\/span>list_to_binary<\/span>(<\/span>"{}"<\/span>);<\/span>\n        Bin<\/span> -><\/span> \n            Bin<\/span>\n    end<\/span>,<\/span>\n    {<\/span>struct<\/span>,<\/span> Struct<\/span>}<\/span> =<\/span> mochijson2<\/span>:<\/span>decode<\/span>(<\/span>Data<\/span>),<\/span>\n    Struct<\/span>.<\/span>\n\n% Parse the URL path<\/span>\nparse_controller_path<\/span>(<\/span>CleanPath<\/span>)<\/span> -><\/span>\n    case<\/span> string<\/span>:<\/span>tokens<\/span>(<\/span>CleanPath<\/span>,<\/span> "/"<\/span>)<\/span> of<\/span>\n        []<\/span> -><\/span> \n            [];<\/span>\n        [_<\/span>RootPath<\/span>|<\/span>Rest<\/span>]<\/span> -><\/span> \n            Rest<\/span>\n    end<\/span>.<\/span>\n\n%% Strip off the query string off the URL<\/span>\nclean_path<\/span>(<\/span>Path<\/span>)<\/span> -><\/span>\n    case<\/span> string<\/span>:<\/span>str<\/span>(<\/span>Path<\/span>,<\/span> "?"<\/span>)<\/span> of<\/span>\n        0<\/span> -><\/span> \n            Path<\/span>;<\/span>\n        N<\/span> -><\/span> \n            string<\/span>:<\/span>substr<\/span>(<\/span>Path<\/span>,<\/span> 1<\/span>,<\/span> string<\/span>:<\/span>len<\/span>(<\/span>Path<\/span>)<\/span> -<\/span> (<\/span>N<\/span>+<\/span>1<\/span>))<\/span>\n    end<\/span>.<\/span>\n\ntop_level_request<\/span>(<\/span>Path<\/span>)<\/span> -><\/span>\n    case<\/span> string<\/span>:<\/span>tokens<\/span>(<\/span>Path<\/span>,<\/span> "/"<\/span>)<\/span> of<\/span>\n        [<\/span>CleanPath<\/span>|_<\/span>Others<\/span>]<\/span> -><\/span> \n            CleanPath<\/span>;<\/span>\n        []<\/span> -><\/span> \n            "home"<\/span>\n    end<\/span>.<\/span>\n<\/pre><\/div>\n