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hiyosi/gist:3850864

Created October 8, 2012 05:27
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  1. hiyosi created this gist Oct 8, 2012.
    118 changes: 118 additions & 0 deletions gistfile1.erl
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,118 @@
    -module(rest).

    -include("/opt/local/lib/erlang/lib/stdlib-1.18.2/include/qlc.hrl").
    -include("/opt/local/lib/yaws/include/yaws_api.hrl").

    -export([out/1, addAirport/4, handle/2 ]).

    -define(RECORD_TYPE, airport).
    -define(RECORD_KEY_FIELD, code).

    -record(?RECORD_TYPE, {?RECORD_KEY_FIELD, city, country, name}).


    out(Arg) ->
    Method = method(Arg),
    io:format("~p:~p ~p Request ~n", [?MODULE, ?LINE, Method]),
    handle(Method, Arg).

    method(Arg) ->
    Rec = Arg#arg.req,
    Rec#http_request.method.


    convert_to_Json(Lines) ->
    Data = [{obj,
    [{airport, Line#?RECORD_TYPE.code},
    {city, Line#?RECORD_TYPE.city},
    {country, Line#?RECORD_TYPE.country},
    {name, Line#?RECORD_TYPE.name}]}
    || Line <- Lines],
    JsonData = {obj, [{data, Data}]},
    rfc4627:encode(JsonData).

    addAirport(Code, City, Country, Name) ->
    NewRec = #?RECORD_TYPE{
    ?RECORD_KEY_FIELD = Code,
    city = City,
    country = Country,
    name = Name},
    io:format("~p:~p Adding Airport ~p~n", [?MODULE, ?LINE, NewRec]),
    Add = fun() ->
    mnesia:write(NewRec)
    end,
    {atomic, _Rec} = mnesia:transaction(Add),
    NewRec.

    handle('GET', _Arg) ->
    io:format("~n ~p:~p GET Request ~n", [?MODULE, ?LINE]),
    Records = do(qlc:q([X || X <- mnesia:table(?RECORD_TYPE)])),
    Json = convert_to_Json(Records),
    io:format("~n ~p:~p GET Request Response ~p ~n", [?MODULE, ?LINE, Json]),
    {html, Json};

    handle('POST', Arg) ->
    {ok, Json, _} = rfc4627:decode(Arg#arg.clidata),
    io:format("~n~p:~p POST request ~p~n", [?MODULE, ?LINE, Json]),
    Airport = rfc4627:get_field(Json, "airport", <<>>),
    City = rfc4627:get_field(Json, "city", <<>>),
    Country = rfc4627:get_field(Json, "country", <<>>),
    Name = rfc4627:get_field(Json, "country", <<>>),
    _Status = addAirport(Airport, City, Country, Name),
    [{status, 201}, {html, Arg#arg.clidata}];

    handle('PUT', Arg) ->
    [IndexValue,_] = string:tokens(Arg#arg.pathinfo),
    {ok, Json, _} = rfc4627:decode(Arg#arg.clidata),
    io:format("~p:~p PUT request ~p ~p~n", [?MODULE, ?LINE, IndexValue, Json]),
    Airport = rfc4627:get_field(Json, "airport", <<>>),
    City = rfc4627:get_field(Json, "city", <<>>),
    Country = rfc4627:get_field(Json, "country", <<>>),
    Name = rfc4627:get_field(Json, "country", <<>>),

    NewRec = #?RECORD_TYPE{
    ?RECORD_KEY_FIELD = Airport,
    city = City,
    country = Country,
    name = Name},

    io:format("~p:~p Renaming ~p", [?MODULE, ?LINE, NewRec]),
    ChangeName = fun() ->
    mnesia:delete({?RECORD_KEY_FIELD, IndexValue}),
    mnesia:write(NewRec)
    end,
    {atomic, _Rec} = mnesia:transaction(ChangeName),
    [{status, 200},
    {html, IndexValue}];

    handle('DELETE', Arg) ->
    [IndexValue, _] = string:tokens(Arg#arg.pathinfo),
    io:format("~p:~p DELETE request ~p", [?MODULE, ?LINE, IndexValue]),
    Delete = fun() ->
    mnesia:delete({?RECORD_KEY_FIELD, IndexValue})
    end,
    Resp = mnesia:transaction(Delete),
    case Resp of
    {atomic, ok} ->
    [{status, 204}];
    {_, Error} ->
    io:format("~p:~p Error ~p ", [?MODULE, ?LINE, Error]),
    [{status, 400}, {html, Error}]
    end;

    handle(Method,_) ->
    [{error, "Unknown method " ++ Method },
    {status, 405},
    {header, "Allow: GET, HEAD, POST, PUT, DELETE"}
    ].

    do(Q) ->
    F = fun() ->
    qlc:e(Q)
    end,
    {atomic, Value} = mnesia:transaction(F),
    Value.