cowboy/test/handlers/echo_h.erl

%% This module echoes back the value the test is interested in.

-module(echo_h).

-export([init/2]).

init(Req, Opts) ->
	case cowboy_req:binding(arg, Req) of
		undefined ->
			echo(cowboy_req:binding(key, Req), Req, Opts);
		Arg ->
			echo_arg(Arg, Req, Opts)
	end.

echo(<<"read_body">>, Req0, Opts) ->
	case Opts of
		#{crash := true} -> ct_helper:ignore(cowboy_req, read_body, 2);
		_ -> ok
	end,
	{_, Body, Req} = case cowboy_req:path(Req0) of
		<<"/100-continue", _/bits>> ->
			cowboy_req:inform(100, Req0),
			cowboy_req:read_body(Req0);
		<<"/delay", _/bits>> ->
			timer:sleep(500),
			cowboy_req:read_body(Req0);
		<<"/full", _/bits>> -> read_body(Req0, <<>>);
		<<"/auto-sync", _/bits>> -> read_body_auto_sync(Req0, <<>>);
		<<"/auto-async", _/bits>> -> read_body_auto_async(Req0, <<>>);
		<<"/length", _/bits>> ->
			{_, _, Req1} = read_body(Req0, <<>>),
			Length = cowboy_req:body_length(Req1),
			{ok, integer_to_binary(Length), Req1};
		<<"/opts", _/bits>> -> cowboy_req:read_body(Req0, Opts);
		<<"/spawn", _/bits>> ->
			Parent = self(),
			Pid = spawn_link(fun() ->
				Parent ! {self(), cowboy_req:read_body(Req0)}
			end),
			receive
				{Pid, Msg} -> Msg
			after 5000 ->
				error(timeout)
			end;
		_ -> cowboy_req:read_body(Req0)
	end,
	{ok, cowboy_req:reply(200, #{}, Body, Req), Opts};
echo(<<"read_urlencoded_body">>, Req0, Opts) ->
	Path = cowboy_req:path(Req0),
	case {Path, Opts} of
		{<<"/opts", _/bits>>, #{crash := true}} -> ct_helper:ignore(cowboy_req, read_body, 2);
		{_, #{crash := true}} -> ct_helper:ignore(cowboy_req, read_urlencoded_body, 2);
		_ -> ok
	end,
	{ok, Body, Req} = case Path of
		<<"/opts", _/bits>> -> cowboy_req:read_urlencoded_body(Req0, Opts);
		<<"/crash", _/bits>> -> cowboy_req:read_urlencoded_body(Req0, Opts);
		_ -> cowboy_req:read_urlencoded_body(Req0)
	end,
	{ok, cowboy_req:reply(200, #{}, value_to_iodata(Body), Req), Opts};
echo(<<"read_and_match_urlencoded_body">>, Req0, Opts) ->
	Path = cowboy_req:path(Req0),
	case {Path, Opts} of
		{<<"/opts", _/bits>>, #{crash := true}} -> ct_helper:ignore(cowboy_req, read_body, 2);
		{_, #{crash := true}} -> ct_helper:ignore(cowboy_req, read_urlencoded_body, 2);
		_ -> ok
	end,
	{ok, Body, Req} = case Path of
		<<"/opts", _/bits>> -> cowboy_req:read_and_match_urlencoded_body([], Req0, Opts);
		<<"/crash", _/bits>> -> cowboy_req:read_and_match_urlencoded_body([], Req0, Opts);
		_ -> cowboy_req:read_and_match_urlencoded_body([], Req0)
	end,
	{ok, cowboy_req:reply(200, #{}, value_to_iodata(Body), Req), Opts};
echo(<<"uri">>, Req, Opts) ->
	Value = case cowboy_req:path_info(Req) of
		[<<"origin">>] -> cowboy_req:uri(Req, #{host => undefined});
		[<<"protocol-relative">>] -> cowboy_req:uri(Req, #{scheme => undefined});
		[<<"no-qs">>] -> cowboy_req:uri(Req, #{qs => undefined});
		[<<"no-path">>] -> cowboy_req:uri(Req, #{path => undefined, qs => undefined});
		[<<"set-port">>] -> cowboy_req:uri(Req, #{port => 123});
		_ -> cowboy_req:uri(Req)
	end,
	{ok, cowboy_req:reply(200, #{}, Value, Req), Opts};
echo(<<"match">>, Req, Opts) ->
	[Type|Fields0] = cowboy_req:path_info(Req),
	Fields = [binary_to_atom(F, latin1) || F <- Fields0],
	Value = case Type of
		<<"qs">> -> cowboy_req:match_qs(Fields, Req);
		<<"qs_with_constraints">> -> cowboy_req:match_qs([{id, integer}], Req);
		<<"cookies">> -> cowboy_req:match_cookies(Fields, Req);
		<<"body_qs">> ->
			%% Note that the Req should not be discarded but for the
			%% purpose of this test this has no ill impacts.
			{ok, Match, _} = cowboy_req:read_and_match_urlencoded_body(Fields, Req),
			Match
	end,
	{ok, cowboy_req:reply(200, #{}, value_to_iodata(Value), Req), Opts};
echo(<<"filter_then_parse_cookies">>, Req0, Opts) ->
	Req = cowboy_req:filter_cookies([cake, color], Req0),
	Value = cowboy_req:parse_cookies(Req),
	{ok, cowboy_req:reply(200, #{}, value_to_iodata(Value), Req), Opts};
echo(What, Req, Opts) ->
	Key = binary_to_atom(What, latin1),
	Value = case cowboy_req:path(Req) of
		<<"/direct/",_/bits>> -> maps:get(Key, Req);
		_ -> cowboy_req:Key(Req)
	end,
	{ok, cowboy_req:reply(200, #{}, value_to_iodata(Value), Req), Opts}.

echo_arg(Arg0, Req, Opts) ->
	F = binary_to_atom(cowboy_req:binding(key, Req), latin1),
	Arg = case F of
		binding -> binary_to_atom(Arg0, latin1);
		_ -> Arg0
	end,
	Value = case cowboy_req:binding(default, Req) of
		undefined -> cowboy_req:F(Arg, Req);
		Default -> cowboy_req:F(Arg, Req, Default)
	end,
	{ok, cowboy_req:reply(200, #{}, value_to_iodata(Value), Req), Opts}.

read_body(Req0, Acc) ->
	case cowboy_req:read_body(Req0) of
		{ok, Data, Req} -> {ok, << Acc/binary, Data/binary >>, Req};
		{more, Data, Req} -> read_body(Req, << Acc/binary, Data/binary >>)
	end.

read_body_auto_sync(Req0, Acc) ->
	Opts = #{length => auto, period => infinity},
	case cowboy_req:read_body(Req0, Opts) of
		{ok, Data, Req} -> {ok, << Acc/binary, Data/binary >>, Req};
		{more, Data, Req} -> read_body_auto_sync(Req, << Acc/binary, Data/binary >>)
	end.

read_body_auto_async(Req, Acc) ->
	read_body_auto_async(Req, make_ref(), Acc).

read_body_auto_async(Req, ReadBodyRef, Acc) ->
	cowboy_req:cast({read_body, self(), ReadBodyRef, auto, infinity}, Req),
	receive
		{request_body, ReadBodyRef, nofin, Data} ->
			read_body_auto_async(Req, ReadBodyRef, <<Acc/binary, Data/binary>>);
		{request_body, ReadBodyRef, fin, _, Data} ->
			{ok, <<Acc/binary, Data/binary>>, Req}
	end.

value_to_iodata(V) when is_integer(V) -> integer_to_binary(V);
value_to_iodata(V) when is_atom(V) -> atom_to_binary(V, latin1);
value_to_iodata(V) when is_list(V); is_tuple(V); is_map(V) -> io_lib:format("~999999p", [V]);
value_to_iodata(V) -> V.