Add experimental cowboy_compress_h stream handler

Currently marked as experimental because it can't be tweaked
(just enabled/disabled) and because it is not documented yet.

test/compress_SUITE.erl

@@ -0,0 +1,129 @@
+%% 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(compress_SUITE).
+-compile(export_all).
+
+-import(ct_helper, [config/2]).
+-import(ct_helper, [doc/1]).
+-import(cowboy_test, [gun_open/1]).
+
+%% ct.
+
+all() ->
+	[
+		{group, http_compress},
+		{group, https_compress},
+		{group, h2_compress},
+		{group, h2c_compress}
+	].
+
+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).
+
+%% Routes.
+
+init_dispatch(Config) ->
+	cowboy_router:compile([{"[...]", [
+		{"/reply/:what", compress_h, reply},
+		{"/stream_reply/:what", compress_h, stream_reply}
+	]}]).
+
+%% Internal.
+
+do_get(Path, ReqHeaders, Config) ->
+	ConnPid = gun_open(Config),
+	Ref = gun:get(ConnPid, Path, ReqHeaders),
+	{response, IsFin, Status, RespHeaders} = gun:await(ConnPid, Ref),
+	{ok, Body} = case IsFin of
+		nofin -> gun:await_body(ConnPid, Ref);
+		fin -> {ok, <<>>}
+	end,
+	gun:close(ConnPid),
+	{Status, RespHeaders, Body}.
+
+%% Tests.
+
+gzip_accept_encoding_missing(Config) ->
+	doc("Don't send accept-encoding; get an uncompressed response."),
+	{200, Headers, _} = do_get("/reply/large",
+		[], Config),
+	false = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	{_, <<"100000">>} = lists:keyfind(<<"content-length">>, 1, Headers),
+	ok.
+
+gzip_accept_encoding_no_gzip(Config) ->
+	doc("Send accept-encoding: compress (unsupported by Cowboy); get an uncompressed response."),
+	{200, Headers, _} = do_get("/reply/large",
+		[{<<"accept-encoding">>, <<"compress">>}], Config),
+	false = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	{_, <<"100000">>} = lists:keyfind(<<"content-length">>, 1, Headers),
+	ok.
+
+gzip_reply_content_encoding(Config) ->
+	doc("Reply with content-encoding header; get an uncompressed response."),
+	{200, Headers, _} = do_get("/reply/content-encoding",
+		[{<<"accept-encoding">>, <<"gzip">>}], Config),
+	%% We set the content-encoding to compress; without actually compressing.
+	{_, <<"compress">>} = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	{_, <<"100000">>} = lists:keyfind(<<"content-length">>, 1, Headers),
+	ok.
+
+gzip_reply_large_body(Config) ->
+	doc("Reply a large body; get a gzipped response."),
+	{200, Headers, GzBody} = do_get("/reply/large",
+		[{<<"accept-encoding">>, <<"gzip">>}], Config),
+	{_, <<"gzip">>} = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	{_, Length} = lists:keyfind(<<"content-length">>, 1, Headers),
+	ct:log("Original length: 100000; compressed: ~s.", [Length]),
+	_ = zlib:gunzip(GzBody),
+	ok.
+
+gzip_reply_sendfile(Config) ->
+	doc("Reply using sendfile; get an uncompressed response."),
+	{200, Headers, Body} = do_get("/reply/sendfile",
+		[{<<"accept-encoding">>, <<"gzip">>}], Config),
+	false = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	ct:log("Body received:~n~p~n", [Body]),
+	ok.
+
+gzip_reply_small_body(Config) ->
+	doc("Reply a small body; get an uncompressed response."),
+	{200, Headers, _} = do_get("/reply/small",
+		[{<<"accept-encoding">>, <<"gzip">>}], Config),
+	false = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	{_, <<"100">>} = lists:keyfind(<<"content-length">>, 1, Headers),
+	ok.
+
+gzip_stream_reply(Config) ->
+	doc("Stream reply; get a gzipped response."),
+	{200, Headers, GzBody} = do_get("/stream_reply/large",
+		[{<<"accept-encoding">>, <<"gzip">>}], Config),
+	{_, <<"gzip">>} = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	_ = zlib:gunzip(GzBody),
+	ok.
+
+gzip_stream_reply_content_encoding(Config) ->
+	doc("Stream reply with content-encoding header; get an uncompressed response."),
+	{200, Headers, Body} = do_get("/stream_reply/content-encoding",
+		[{<<"accept-encoding">>, <<"gzip">>}], Config),
+	{_, <<"compress">>} = lists:keyfind(<<"content-encoding">>, 1, Headers),
+	100000 = iolist_size(Body),
+	ok.