Separate request/4,5,6 into headers/4,5 and request/5,6

This cleaner separation gets rid of the implicit body check
that was causing issues for many users. Now the body is
either given explicitly or it is expected via future
gun:data/3 calls.

3 files changed, 51 insertions, 38 deletions

diff --git a/src/gun.erl b/src/gun.erl
index 1e83979..10ae2a7 100644
--- a/src/gun.erl
+++ b/src/gun.erl
@@ -49,7 +49,10 @@
 -export([put/3]).
 -export([put/4]).
 -export([put/5]).
--export([request/4]).
+
+%% Generic requests interface.
+-export([headers/4]).
+-export([headers/5]).
 -export([request/5]).
 -export([request/6]).
 
@@ -316,11 +319,11 @@ shutdown(ServerPid) ->
 
 -spec delete(pid(), iodata()) -> reference().
 delete(ServerPid, Path) ->
-	request(ServerPid, <<"DELETE">>, Path, []).
+	request(ServerPid, <<"DELETE">>, Path, [], <<>>).
 
 -spec delete(pid(), iodata(), headers()) -> reference().
 delete(ServerPid, Path, Headers) ->
-	request(ServerPid, <<"DELETE">>, Path, Headers).
+	request(ServerPid, <<"DELETE">>, Path, Headers, <<>>).
 
 -spec delete(pid(), iodata(), headers(), req_opts()) -> reference().
 delete(ServerPid, Path, Headers, ReqOpts) ->
@@ -328,11 +331,11 @@ delete(ServerPid, Path, Headers, ReqOpts) ->
 
 -spec get(pid(), iodata()) -> reference().
 get(ServerPid, Path) ->
-	request(ServerPid, <<"GET">>, Path, []).
+	request(ServerPid, <<"GET">>, Path, [], <<>>).
 
 -spec get(pid(), iodata(), headers()) -> reference().
 get(ServerPid, Path, Headers) ->
-	request(ServerPid, <<"GET">>, Path, Headers).
+	request(ServerPid, <<"GET">>, Path, Headers, <<>>).
 
 -spec get(pid(), iodata(), headers(), req_opts()) -> reference().
 get(ServerPid, Path, Headers, ReqOpts) ->
@@ -340,11 +343,11 @@ get(ServerPid, Path, Headers, ReqOpts) ->
 
 -spec head(pid(), iodata()) -> reference().
 head(ServerPid, Path) ->
-	request(ServerPid, <<"HEAD">>, Path, []).
+	request(ServerPid, <<"HEAD">>, Path, [], <<>>).
 
 -spec head(pid(), iodata(), headers()) -> reference().
 head(ServerPid, Path, Headers) ->
-	request(ServerPid, <<"HEAD">>, Path, Headers).
+	request(ServerPid, <<"HEAD">>, Path, Headers, <<>>).
 
 -spec head(pid(), iodata(), headers(), req_opts()) -> reference().
 head(ServerPid, Path, Headers, ReqOpts) ->
@@ -352,11 +355,11 @@ head(ServerPid, Path, Headers, ReqOpts) ->
 
 -spec options(pid(), iodata()) -> reference().
 options(ServerPid, Path) ->
-	request(ServerPid, <<"OPTIONS">>, Path, []).
+	request(ServerPid, <<"OPTIONS">>, Path, [], <<>>).
 
 -spec options(pid(), iodata(), headers()) -> reference().
 options(ServerPid, Path, Headers) ->
-	request(ServerPid, <<"OPTIONS">>, Path, Headers).
+	request(ServerPid, <<"OPTIONS">>, Path, Headers, <<>>).
 
 -spec options(pid(), iodata(), headers(), req_opts()) -> reference().
 options(ServerPid, Path, Headers, ReqOpts) ->
@@ -364,9 +367,11 @@ options(ServerPid, Path, Headers, ReqOpts) ->
 
 -spec patch(pid(), iodata(), headers()) -> reference().
 patch(ServerPid, Path, Headers) ->
-	request(ServerPid, <<"PATCH">>, Path, Headers).
+	headers(ServerPid, <<"PATCH">>, Path, Headers).
 
--spec patch(pid(), iodata(), headers(), iodata()) -> reference().
+-spec patch(pid(), iodata(), headers(), iodata() | req_opts()) -> reference().
+patch(ServerPid, Path, Headers, ReqOpts) when is_map(ReqOpts) ->
+	headers(ServerPid, <<"PATCH">>, Path, Headers, ReqOpts);
 patch(ServerPid, Path, Headers, Body) ->
 	request(ServerPid, <<"PATCH">>, Path, Headers, Body).
 
@@ -376,9 +381,11 @@ patch(ServerPid, Path, Headers, Body, ReqOpts) ->
 
 -spec post(pid(), iodata(), headers()) -> reference().
 post(ServerPid, Path, Headers) ->
-	request(ServerPid, <<"POST">>, Path, Headers).
+	headers(ServerPid, <<"POST">>, Path, Headers).
 
--spec post(pid(), iodata(), headers(), iodata()) -> reference().
+-spec post(pid(), iodata(), headers(), iodata() | req_opts()) -> reference().
+post(ServerPid, Path, Headers, ReqOpts) when is_map(ReqOpts) ->
+	headers(ServerPid, <<"POST">>, Path, Headers, ReqOpts);
 post(ServerPid, Path, Headers, Body) ->
 	request(ServerPid, <<"POST">>, Path, Headers, Body).
 
@@ -388,9 +395,11 @@ post(ServerPid, Path, Headers, Body, ReqOpts) ->
 
 -spec put(pid(), iodata(), headers()) -> reference().
 put(ServerPid, Path, Headers) ->
-	request(ServerPid, <<"PUT">>, Path, Headers).
+	headers(ServerPid, <<"PUT">>, Path, Headers).
 
--spec put(pid(), iodata(), headers(), iodata()) -> reference().
+-spec put(pid(), iodata(), headers(), iodata() | req_opts()) -> reference().
+put(ServerPid, Path, Headers, ReqOpts) when is_map(ReqOpts) ->
+	headers(ServerPid, <<"PUT">>, Path, Headers, ReqOpts);
 put(ServerPid, Path, Headers, Body) ->
 	request(ServerPid, <<"PUT">>, Path, Headers, Body).
 
@@ -398,9 +407,19 @@ put(ServerPid, Path, Headers, Body) ->
 put(ServerPid, Path, Headers, Body, ReqOpts) ->
 	request(ServerPid, <<"PUT">>, Path, Headers, Body, ReqOpts).
 
--spec request(pid(), iodata(), iodata(), headers()) -> reference().
-request(ServerPid, Method, Path, Headers) ->
-	request(ServerPid, Method, Path, Headers, <<>>, #{}).
+%% Generic requests interface.
+
+-spec headers(pid(), iodata(), iodata(), headers()) -> reference().
+headers(ServerPid, Method, Path, Headers) ->
+	headers(ServerPid, Method, Path, Headers, #{}).
+
+%% @todo Accept header names as maps.
+-spec headers(pid(), iodata(), iodata(), headers(), req_opts()) -> reference().
+headers(ServerPid, Method, Path, Headers, ReqOpts) ->
+	StreamRef = make_ref(),
+	ReplyTo = maps:get(reply_to, ReqOpts, self()),
+	gen_statem:cast(ServerPid, {headers, ReplyTo, StreamRef, Method, Path, Headers}),
+	StreamRef.
 
 -spec request(pid(), iodata(), iodata(), headers(), iodata()) -> reference().
 request(ServerPid, Method, Path, Headers, Body) ->
@@ -729,15 +748,17 @@ connected(info, keepalive, State=#state{protocol=Protocol, protocol_state=ProtoS
 	ProtoState2 = Protocol:keepalive(ProtoState),
 	{keep_state, keepalive_timeout(State#state{protocol_state=ProtoState2})};
 %% Public HTTP interface.
+connected(cast, {headers, ReplyTo, StreamRef, Method, Path, Headers},
+		State=#state{origin_host=Host, origin_port=Port,
+			protocol=Protocol, protocol_state=ProtoState}) ->
+	ProtoState2 = Protocol:headers(ProtoState,
+		StreamRef, ReplyTo, Method, Host, Port, Path, Headers),
+	{keep_state, State#state{protocol_state=ProtoState2}};
 connected(cast, {request, ReplyTo, StreamRef, Method, Path, Headers, Body},
 		State=#state{origin_host=Host, origin_port=Port,
 			protocol=Protocol, protocol_state=ProtoState}) ->
-	ProtoState2 = case Body of
-		<<>> -> Protocol:request(ProtoState,
-			StreamRef, ReplyTo, Method, Host, Port, Path, Headers);
-		_ -> Protocol:request(ProtoState,
-			StreamRef, ReplyTo, Method, Host, Port, Path, Headers, Body)
-	end,
+	ProtoState2 = Protocol:request(ProtoState,
+		StreamRef, ReplyTo, Method, Host, Port, Path, Headers, Body),
 	{keep_state, State#state{protocol_state=ProtoState2}};
 %% @todo Do we want to reject ReplyTo if it's not the process
 %% who initiated the connection? For both data and cancel.
diff --git a/src/gun_http.erl b/src/gun_http.erl
index 57f72c7..5229a6d 100644
--- a/src/gun_http.erl
+++ b/src/gun_http.erl
@@ -20,7 +20,7 @@
 -export([handle/2]).
 -export([close/2]).
 -export([keepalive/1]).
--export([request/8]).
+-export([headers/8]).
 -export([request/9]).
 -export([data/5]).
 -export([connect/5]).
@@ -330,7 +330,7 @@ keepalive(State=#http_state{socket=Socket, transport=Transport, out=head}) ->
 keepalive(State) ->
 	State.
 
-request(State=#http_state{socket=Socket, transport=Transport, version=Version,
+headers(State=#http_state{socket=Socket, transport=Transport, version=Version,
 		out=head}, StreamRef, ReplyTo, Method, Host, Port, Path, Headers) ->
 	Host2 = case Host of
 		{local, _SocketPath} -> <<>>;
@@ -509,10 +509,7 @@ request_io_from_headers(Headers) ->
 		{_, Length} ->
 			{body, cow_http_hd:parse_content_length(Length)};
 		_ ->
-			case lists:keymember(<<"content-type">>, 1, Headers) of
-				true -> body_chunked;
-				false -> head
-			end
+			body_chunked
 	end.
 
 response_io_from_headers(<<"HEAD">>, _, _, _) ->
diff --git a/src/gun_http2.erl b/src/gun_http2.erl
index 6538083..f5cf834 100644
--- a/src/gun_http2.erl
+++ b/src/gun_http2.erl
@@ -20,7 +20,7 @@
 -export([handle/2]).
 -export([close/2]).
 -export([keepalive/1]).
--export([request/8]).
+-export([headers/8]).
 -export([request/9]).
 -export([data/5]).
 -export([cancel/3]).
@@ -240,19 +240,14 @@ keepalive(State=#http2_state{socket=Socket, transport=Transport}) ->
 	Transport:send(Socket, cow_http2:ping(0)),
 	State.
 
-request(State=#http2_state{socket=Socket, transport=Transport,
+headers(State=#http2_state{socket=Socket, transport=Transport,
 		http2_machine=HTTP2Machine0, streams=Streams},
 		StreamRef, ReplyTo, Method, Host, Port, Path, Headers0) ->
-	IsFin0 = case (false =/= lists:keyfind(<<"content-type">>, 1, Headers0))
-			orelse (false =/= lists:keyfind(<<"content-length">>, 1, Headers0)) of
-		true -> nofin;
-		false -> fin
-	end,
 	{ok, StreamID, HTTP2Machine1} = cow_http2_machine:init_stream(
 		iolist_to_binary(Method), HTTP2Machine0),
 	{ok, PseudoHeaders, Headers} = prepare_headers(State, Method, Host, Port, Path, Headers0),
 	{ok, IsFin, HeaderBlock, HTTP2Machine} = cow_http2_machine:prepare_headers(
-		StreamID, HTTP2Machine1, IsFin0, PseudoHeaders, Headers),
+		StreamID, HTTP2Machine1, nofin, PseudoHeaders, Headers),
 	Transport:send(Socket, cow_http2:headers(StreamID, IsFin, HeaderBlock)),
 	Stream = #stream{id=StreamID, ref=StreamRef, reply_to=ReplyTo},
 	State#http2_state{http2_machine=HTTP2Machine, streams=[Stream|Streams]}.