cowboy/test/rest_handler_SUITE.erl

%% Copyright (c) 2017, Loïc Hoguin <essen@ninenines.eu>
%%
%% Permission to use, copy, modify, and/or distribute this software for any
%% purpose with or without fee is hereby granted, provided that the above
%% copyright notice and this permission notice appear in all copies.
%%
%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

-module(rest_handler_SUITE).
-compile(export_all).
-compile(nowarn_export_all).

-import(ct_helper, [config/2]).
-import(ct_helper, [doc/1]).
-import(cowboy_test, [gun_open/1]).

%% ct.

all() ->
	cowboy_test:common_all().

groups() ->
	cowboy_test:common_groups(ct_helper:all(?MODULE)).

init_per_group(Name, Config) ->
	cowboy_test:init_common_groups(Name, Config, ?MODULE).

end_per_group(Name, _) ->
	cowboy:stop_listener(Name).

%% Dispatch configuration.

init_dispatch(_) ->
	cowboy_router:compile([{'_', [
		{"/", rest_hello_h, []},
		{"/charsets_provided", charsets_provided_h, []},
		{"/charsets_provided_empty", charsets_provided_empty_h, []},
		{"/charset_in_content_types_provided",
			charset_in_content_types_provided_h, []},
		{"/charset_in_content_types_provided_implicit",
			charset_in_content_types_provided_implicit_h, []},
		{"/charset_in_content_types_provided_implicit_no_callback",
			charset_in_content_types_provided_implicit_no_callback_h, []},
		{"/provide_callback_missing", provide_callback_missing_h, []},
		{"/rate_limited", rate_limited_h, []},
		{"/stop_handler", stop_handler_h, []},
		{"/switch_handler", switch_handler_h, run},
		{"/switch_handler_opts", switch_handler_h, hibernate}
	]}]).

%% Internal.

do_decode(Headers, Body) ->
	case lists:keyfind(<<"content-encoding">>, 1, Headers) of
		{_, <<"gzip">>} -> zlib:gunzip(Body);
		_ -> Body
	end.

%% Tests.

error_on_malformed_if_match(Config) ->
	doc("A malformed If-Match header must result in a 400 response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/", [
		{<<"accept-encoding">>, <<"gzip">>},
		{<<"if-match">>, <<"bad">>}
	]),
	{response, _, 400, _} = gun:await(ConnPid, Ref),
	ok.

error_on_malformed_if_none_match(Config) ->
	doc("A malformed If-None-Match header must result in a 400 response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/", [
		{<<"accept-encoding">>, <<"gzip">>},
		{<<"if-none-match">>, <<"bad">>}
	]),
	{response, _, 400, _} = gun:await(ConnPid, Ref),
	ok.

charset_in_content_types_provided(Config) ->
	doc("When a charset is matched explictly in content_types_provided, "
		"that charset is used and the charsets_provided callback is ignored."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charset_in_content_types_provided", [
		{<<"accept">>, <<"text/plain;charset=utf-8">>},
		{<<"accept-charset">>, <<"utf-16, utf-8;q=0.5">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"text/plain; charset=utf-8">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charset_in_content_types_provided_implicit_match(Config) ->
	doc("When a charset is matched implicitly in content_types_provided, "
		"the charsets_provided callback is used to determine if the media "
		"type will match."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charset_in_content_types_provided_implicit", [
		{<<"accept">>, <<"text/plain;charset=utf-16">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"text/plain; charset=utf-16">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charset_in_content_types_provided_implicit_nomatch(Config) ->
	doc("When a charset is matched implicitly in content_types_provided, "
		"the charsets_provided callback is used to determine if the media "
		"type will match. If it doesn't, try the next media type."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charset_in_content_types_provided_implicit", [
		{<<"accept">>, <<"text/plain;charset=utf-32, text/plain">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	%% We end up with the first charset listed in charsets_provided.
	{_, <<"text/plain; charset=utf-8">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charset_in_content_types_provided_implicit_nomatch_error(Config) ->
	doc("When a charset is matched implicitly in content_types_provided, "
		"the charsets_provided callback is used to determine if the media "
		"type will match. If it doesn't, and there's no other media type, "
		"a 406 is returned."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charset_in_content_types_provided_implicit", [
		{<<"accept">>, <<"text/plain;charset=utf-32">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 406, _} = gun:await(ConnPid, Ref),
	ok.

charset_in_content_types_provided_implicit_no_callback(Config) ->
	doc("When a charset is matched implicitly in content_types_provided, "
		"and the charsets_provided callback is not exported, the media "
		"type will match but the charset will be ignored like all other "
		"parameters."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charset_in_content_types_provided_implicit_no_callback", [
		{<<"accept">>, <<"text/plain;charset=utf-32">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	%% The charset is ignored as if it was any other parameter.
	{_, <<"text/plain">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charsets_provided_match_text(Config) ->
	doc("When the media type is text and the charsets_provided callback exists "
		"and the accept-charset header was sent, the selected charset is sent "
		"back in the content-type of the response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided", [
		{<<"accept">>, <<"text/plain">>},
		{<<"accept-charset">>, <<"utf-8;q=0.5, utf-16">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"text/plain; charset=utf-16">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charsets_provided_match_other(Config) ->
	doc("When the media type is not text and the charsets_provided callback exists "
		"and the accept-charset header was sent, the selected charset is not sent "
		"back in the content-type of the response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided", [
		{<<"accept">>, <<"application/json">>},
		{<<"accept-charset">>, <<"utf-8;q=0.5, utf-16">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"application/json">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charsets_provided_wildcard_text(Config) ->
	doc("When the media type is text and the charsets_provided callback exists "
		"and a wildcard accept-charset header was sent, the selected charset is sent "
		"back in the content-type of the response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided", [
		{<<"accept">>, <<"text/plain">>},
		{<<"accept-charset">>, <<"*">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"text/plain; charset=utf-8">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charsets_provided_wildcard_other(Config) ->
	doc("When the media type is not text and the charsets_provided callback exists "
		"and a wildcard accept-charset header was sent, the selected charset is not sent "
		"back in the content-type of the response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided", [
		{<<"accept">>, <<"application/json">>},
		{<<"accept-charset">>, <<"*">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"application/json">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charsets_provided_nomatch(Config) ->
	doc("Regardless of the media type negotiated, if no charset is found in the "
		"accept-charset header match a charset configured in charsets_provided, "
		"then a 406 not acceptable response is sent back."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided", [
		{<<"accept">>, <<"text/plain">>},
		{<<"accept-charset">>, <<"utf-8;q=0, iso-8859-1">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 406, _} = gun:await(ConnPid, Ref),
	ok.

charsets_provided_noheader_text(Config) ->
	doc("When the media type is text and the charsets_provided callback exists "
		"but the accept-charset header was not sent, the first charset in the "
		"list is selected and sent back in the content-type of the response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided", [
		{<<"accept">>, <<"text/plain">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"text/plain; charset=utf-8">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charsets_provided_noheader_other(Config) ->
	doc("When the media type is not text and the charsets_provided callback exists "
		"but the accept-charset header was not sent, the first charset in the "
		"list is selected but is not sent back in the content-type of the response."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided", [
		{<<"accept">>, <<"application/json">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 200, Headers} = gun:await(ConnPid, Ref),
	{_, <<"application/json">>} = lists:keyfind(<<"content-type">>, 1, Headers),
	ok.

charsets_provided_empty(Config) ->
	doc("Regardless of the media type negotiated, if the charsets_provided "
		"callback returns an empty list a 406 not acceptable response is sent back."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided_empty", [
		{<<"accept">>, <<"text/plain">>},
		{<<"accept-charset">>, <<"utf-8q=0.5, utf-16">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 406, _} = gun:await(ConnPid, Ref),
	ok.

charsets_provided_empty_wildcard(Config) ->
	doc("Regardless of the media type negotiated, if the charsets_provided "
		"callback returns an empty list a 406 not acceptable response is sent back."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided_empty", [
		{<<"accept">>, <<"text/plain">>},
		{<<"accept-charset">>, <<"*">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 406, _} = gun:await(ConnPid, Ref),
	ok.

charsets_provided_empty_noheader(Config) ->
	doc("Regardless of the media type negotiated, if the charsets_provided "
		"callback returns an empty list a 406 not acceptable response is sent back."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/charsets_provided_empty", [
		{<<"accept">>, <<"text/plain">>},
		{<<"accept-encoding">>, <<"gzip">>}
	]),
	{response, _, 406, _} = gun:await(ConnPid, Ref),
	ok.

provide_callback_missing(Config) ->
	doc("A 500 response must be sent when the ProvideCallback can't be called."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/provide_callback_missing", [{<<"accept-encoding">>, <<"gzip">>}]),
	{response, fin, 500, _} = gun:await(ConnPid, Ref),
	ok.

rate_limited(Config) ->
	doc("A 429 response must be sent when the rate_limited callback returns true. "
		"The retry-after header is specified as an integer."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/rate_limited?true", [{<<"accept-encoding">>, <<"gzip">>}]),
	{response, fin, 429, Headers} = gun:await(ConnPid, Ref),
	{_, <<"3600">>} = lists:keyfind(<<"retry-after">>, 1, Headers),
	ok.

rate_limited_datetime(Config) ->
	doc("A 429 response must be sent when the rate_limited callback returns true. "
		"The retry-after header is specified as a date/time tuple."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/rate_limited?true-date", [{<<"accept-encoding">>, <<"gzip">>}]),
	{response, fin, 429, Headers} = gun:await(ConnPid, Ref),
	{_, <<"Fri, 22 Feb 2222 11:11:11 GMT">>} = lists:keyfind(<<"retry-after">>, 1, Headers),
	ok.

rate_not_limited(Config) ->
	doc("A success response must be sent when the rate_limited callback returns false."),
	ConnPid = gun_open(Config),
	Ref = gun:get(ConnPid, "/rate_limited?false", [{<<"accept-encoding">>, <<"gzip">>}]),
	{response, nofin, 200, _} = gun:await(ConnPid, Ref),
	ok.

stop_handler_allowed_methods(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_allow_missing_post(Config) ->
	do_req_body_stop_handler(Config, post, ?FUNCTION_NAME).

stop_handler_charsets_provided(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_content_types_accepted(Config) ->
	do_req_body_stop_handler(Config, post, ?FUNCTION_NAME).

stop_handler_content_types_provided(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_delete_completed(Config) ->
	do_no_body_stop_handler(Config, delete, ?FUNCTION_NAME).

stop_handler_delete_resource(Config) ->
	do_no_body_stop_handler(Config, delete, ?FUNCTION_NAME).

stop_handler_forbidden(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_is_authorized(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_is_conflict(Config) ->
	do_req_body_stop_handler(Config, put, ?FUNCTION_NAME).

stop_handler_known_methods(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_languages_provided(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_malformed_request(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_moved_permanently(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_moved_temporarily(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_multiple_choices(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_options(Config) ->
	do_no_body_stop_handler(Config, options, ?FUNCTION_NAME).

stop_handler_previously_existed(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_rate_limited(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_resource_exists(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_service_available(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_uri_too_long(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_valid_content_headers(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_valid_entity_length(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

stop_handler_accept(Config) ->
	do_req_body_stop_handler(Config, post, ?FUNCTION_NAME).

stop_handler_provide(Config) ->
	do_no_body_stop_handler(Config, get, ?FUNCTION_NAME).

do_no_body_stop_handler(Config, Method, StateName0) ->
	doc("Send a response manually and stop the REST handler."),
	ConnPid = gun_open(Config),
	"stop_handler_" ++ StateName = atom_to_list(StateName0),
	Ref = gun:Method(ConnPid, "/stop_handler?" ++ StateName,
		[{<<"accept-encoding">>, <<"gzip">>}]),
	{response, fin, 248, _} = gun:await(ConnPid, Ref),
	ok.

do_req_body_stop_handler(Config, Method, StateName0) ->
	doc("Send a response manually and stop the REST handler."),
	ConnPid = gun_open(Config),
	"stop_handler_" ++ StateName = atom_to_list(StateName0),
	Ref = gun:Method(ConnPid, "/stop_handler?" ++ StateName, [
		{<<"accept-encoding">>, <<"gzip">>},
		{<<"content-type">>, <<"text/plain">>}
	], <<"Hocus PocuSwitch!">>),
	{response, fin, 248, _} = gun:await(ConnPid, Ref),
	ok.

switch_handler_allowed_methods(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_allow_missing_post(Config) ->
	do_req_body_switch_handler(Config, post, ?FUNCTION_NAME).

switch_handler_charsets_provided(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_content_types_accepted(Config) ->
	do_req_body_switch_handler(Config, post, ?FUNCTION_NAME).

switch_handler_content_types_provided(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_delete_completed(Config) ->
	do_no_body_switch_handler(Config, delete, ?FUNCTION_NAME).

switch_handler_delete_resource(Config) ->
	do_no_body_switch_handler(Config, delete, ?FUNCTION_NAME).

switch_handler_forbidden(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_is_authorized(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_is_conflict(Config) ->
	do_req_body_switch_handler(Config, put, ?FUNCTION_NAME).

switch_handler_known_methods(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_languages_provided(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_malformed_request(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_moved_permanently(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_moved_temporarily(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_multiple_choices(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_options(Config) ->
	do_no_body_switch_handler(Config, options, ?FUNCTION_NAME).

switch_handler_previously_existed(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_rate_limited(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_resource_exists(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_service_available(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_uri_too_long(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_valid_content_headers(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_valid_entity_length(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

switch_handler_accept(Config) ->
	do_req_body_switch_handler(Config, post, ?FUNCTION_NAME).

switch_handler_provide(Config) ->
	do_no_body_switch_handler(Config, get, ?FUNCTION_NAME).

do_no_body_switch_handler(Config, Method, StateName0) ->
	doc("Switch REST to loop handler for streaming the response body, "
		"with and without options."),
	"switch_handler_" ++ StateName = atom_to_list(StateName0),
	do_no_body_switch_handler1(Config, Method, "/switch_handler?" ++ StateName),
	do_no_body_switch_handler1(Config, Method, "/switch_handler_opts?" ++ StateName).

do_no_body_switch_handler1(Config, Method, Path) ->
	ConnPid = gun_open(Config),
	Ref = gun:Method(ConnPid, Path, [{<<"accept-encoding">>, <<"gzip">>}]),
	{response, nofin, 200, Headers} = gun:await(ConnPid, Ref),
	{ok, Body} = gun:await_body(ConnPid, Ref),
	<<"Hello\nstreamed\nworld!\n">> = do_decode(Headers, Body),
	ok.

do_req_body_switch_handler(Config, Method, StateName0) ->
	doc("Switch REST to loop handler for streaming the response body, "
		"with and without options."),
	"switch_handler_" ++ StateName = atom_to_list(StateName0),
	do_req_body_switch_handler1(Config, Method, "/switch_handler?" ++ StateName),
	do_req_body_switch_handler1(Config, Method, "/switch_handler_opts?" ++ StateName).

do_req_body_switch_handler1(Config, Method, Path) ->
	ConnPid = gun_open(Config),
	Ref = gun:Method(ConnPid, Path, [
		{<<"accept-encoding">>, <<"gzip">>},
		{<<"content-type">>, <<"text/plain">>}
	], <<"Hocus PocuSwitch!">>),
	{response, nofin, 200, Headers} = gun:await(ConnPid, Ref),
	{ok, Body} = gun:await_body(ConnPid, Ref),
	<<"Hello\nstreamed\nworld!\n">> = do_decode(Headers, Body),
	ok.