Stage 4

src/handlers/handler_search.erl

@@ -0,0 +1,104 @@
+-module(handler_search).
+-include("records.hrl").
+
+-export([init/2]).
+
+init(Req, Opts) ->
+  handle(Req, Opts).
+
+handle(Req, _Opts) ->
+  case cowboy_req:method(Req) of
+    <<"GET">> -> search(Req);
+    _ -> send_error(Req, 405, <<"Method not allowed">>)
+  end.
+
+search(Req) ->
+  case handler_auth:authenticate(Req) of
+    {ok, UserId, Req1} ->
+      Qs = cowboy_req:parse_qs(Req1),
+
+      Type = proplists:get_value(<<"type">>, Qs, undefined),
+      Query = proplists:get_value(<<"q">>, Qs, undefined),
+
+      Params = parse_params(Qs),
+
+      case logic_search:search(Type, Query, UserId, Params) of
+        {ok, Total, Results} ->
+          Response = #{
+            total => Total,
+            limit => maps:get(limit, Params, 20),
+            offset => maps:get(offset, Params, 0),
+            results => Results
+          },
+          send_json(Req1, 200, Response);
+        {error, _} ->
+          send_error(Req1, 500, <<"Search failed">>)
+      end;
+    {error, Code, Message, Req1} ->
+      send_error(Req1, Code, Message)
+  end.
+
+parse_params(Qs) ->
+  Params = #{
+    limit => parse_int_param(Qs, <<"limit">>, 20),
+    offset => parse_int_param(Qs, <<"offset">>, 0),
+    tags => proplists:get_value(<<"tags">>, Qs),
+    sort => proplists:get_value(<<"sort">>, Qs, <<"start_time">>),
+    order => proplists:get_value(<<"order">>, Qs, <<"asc">>)
+  },
+
+  Params1 = case {parse_float_param(Qs, <<"lat">>), parse_float_param(Qs, <<"lon">>)} of
+              {{ok, Lat}, {ok, Lon}} ->
+                Radius = parse_int_param(Qs, <<"radius">>, 10),
+                Params#{lat => Lat, lon => Lon, radius => Radius};
+              _ -> Params
+            end,
+
+  Params2 = case {parse_datetime_param(Qs, <<"from">>), parse_datetime_param(Qs, <<"to">>)} of
+              {{ok, From}, {ok, To}} ->
+                Params1#{from => From, to => To};
+              {{ok, From}, error} ->
+                Params1#{from => From};
+              {error, {ok, To}} ->
+                Params1#{to => To};
+              _ -> Params1
+            end,
+
+  Params2.
+
+parse_int_param(Qs, Key, Default) ->
+  case proplists:get_value(Key, Qs) of
+    undefined -> Default;
+    Val -> binary_to_integer(Val)
+  end.
+
+parse_float_param(Qs, Key) ->
+  case proplists:get_value(Key, Qs) of
+    undefined -> error;
+    Val -> {ok, binary_to_float(Val)}
+  end.
+
+parse_datetime_param(Qs, Key) ->
+  case proplists:get_value(Key, Qs) of
+    undefined -> error;
+    Val ->
+      try
+        [DateStr, TimeStr] = string:split(Val, "T"),
+        TimeStrNoZ = string:trim(TimeStr, trailing, "Z"),
+
+        [Y, M, D] = [binary_to_integer(X) || X <- string:split(DateStr, "-", all)],
+        [H, Min, S] = [binary_to_integer(X) || X <- string:split(TimeStrNoZ, ":", all)],
+
+        {ok, {{Y, M, D}, {H, Min, S}}}
+      catch
+        _:_ -> error
+      end
+  end.
+
+send_json(Req, Status, Data) ->
+  Body = jsx:encode(Data),
+  cowboy_req:reply(Status, #{<<"content-type">> => <<"application/json">>}, Body, Req).
+
+send_error(Req, Status, Message) ->
+  Body = jsx:encode(#{error => Message}),
+  cowboy_req:reply(Status, #{<<"content-type">> => <<"application/json">>}, Body, Req).