Lowercase header names automatically and accept more types

Header names can now be provided as binary, string or atom
and Gun no longer requires them to be in lowercase. The list
of headers can also be provided as a map as well.

1 files changed, 43 insertions, 30 deletions

diff --git a/src/gun.erl b/src/gun.erl
index 55e70dd..75092f1 100644
--- a/src/gun.erl
+++ b/src/gun.erl
@@ -94,7 +94,9 @@
 -export([not_connected/3]).
 -export([connected/3]).
 
--type headers() :: [{binary(), iodata()}].
+-type req_headers() :: [{binary() | string() | atom(), iodata()}]
+	| #{binary() | string() | atom() => iodata()}.
+-export_type([req_headers/0]).
 
 -type ws_close_code() :: 1000..4999.
 -type ws_frame() :: close | ping | pong
@@ -320,11 +322,11 @@ shutdown(ServerPid) ->
 delete(ServerPid, Path) ->
 	request(ServerPid, <<"DELETE">>, Path, [], <<>>).
 
--spec delete(pid(), iodata(), headers()) -> reference().
+-spec delete(pid(), iodata(), req_headers()) -> reference().
 delete(ServerPid, Path, Headers) ->
 	request(ServerPid, <<"DELETE">>, Path, Headers, <<>>).
 
--spec delete(pid(), iodata(), headers(), req_opts()) -> reference().
+-spec delete(pid(), iodata(), req_headers(), req_opts()) -> reference().
 delete(ServerPid, Path, Headers, ReqOpts) ->
 	request(ServerPid, <<"DELETE">>, Path, Headers, <<>>, ReqOpts).
 
@@ -332,11 +334,11 @@ delete(ServerPid, Path, Headers, ReqOpts) ->
 get(ServerPid, Path) ->
 	request(ServerPid, <<"GET">>, Path, [], <<>>).
 
--spec get(pid(), iodata(), headers()) -> reference().
+-spec get(pid(), iodata(), req_headers()) -> reference().
 get(ServerPid, Path, Headers) ->
 	request(ServerPid, <<"GET">>, Path, Headers, <<>>).
 
--spec get(pid(), iodata(), headers(), req_opts()) -> reference().
+-spec get(pid(), iodata(), req_headers(), req_opts()) -> reference().
 get(ServerPid, Path, Headers, ReqOpts) ->
 	request(ServerPid, <<"GET">>, Path, Headers, <<>>, ReqOpts).
 
@@ -344,11 +346,11 @@ get(ServerPid, Path, Headers, ReqOpts) ->
 head(ServerPid, Path) ->
 	request(ServerPid, <<"HEAD">>, Path, [], <<>>).
 
--spec head(pid(), iodata(), headers()) -> reference().
+-spec head(pid(), iodata(), req_headers()) -> reference().
 head(ServerPid, Path, Headers) ->
 	request(ServerPid, <<"HEAD">>, Path, Headers, <<>>).
 
--spec head(pid(), iodata(), headers(), req_opts()) -> reference().
+-spec head(pid(), iodata(), req_headers(), req_opts()) -> reference().
 head(ServerPid, Path, Headers, ReqOpts) ->
 	request(ServerPid, <<"HEAD">>, Path, Headers, <<>>, ReqOpts).
 
@@ -356,82 +358,93 @@ head(ServerPid, Path, Headers, ReqOpts) ->
 options(ServerPid, Path) ->
 	request(ServerPid, <<"OPTIONS">>, Path, [], <<>>).
 
--spec options(pid(), iodata(), headers()) -> reference().
+-spec options(pid(), iodata(), req_headers()) -> reference().
 options(ServerPid, Path, Headers) ->
 	request(ServerPid, <<"OPTIONS">>, Path, Headers, <<>>).
 
--spec options(pid(), iodata(), headers(), req_opts()) -> reference().
+-spec options(pid(), iodata(), req_headers(), req_opts()) -> reference().
 options(ServerPid, Path, Headers, ReqOpts) ->
 	request(ServerPid, <<"OPTIONS">>, Path, Headers, <<>>, ReqOpts).
 
--spec patch(pid(), iodata(), headers()) -> reference().
+-spec patch(pid(), iodata(), req_headers()) -> reference().
 patch(ServerPid, Path, Headers) ->
 	headers(ServerPid, <<"PATCH">>, Path, Headers).
 
--spec patch(pid(), iodata(), headers(), iodata() | req_opts()) -> reference().
+-spec patch(pid(), iodata(), req_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).
 
--spec patch(pid(), iodata(), headers(), iodata(), req_opts()) -> reference().
+-spec patch(pid(), iodata(), req_headers(), iodata(), req_opts()) -> reference().
 patch(ServerPid, Path, Headers, Body, ReqOpts) ->
 	request(ServerPid, <<"PATCH">>, Path, Headers, Body, ReqOpts).
 
--spec post(pid(), iodata(), headers()) -> reference().
+-spec post(pid(), iodata(), req_headers()) -> reference().
 post(ServerPid, Path, Headers) ->
 	headers(ServerPid, <<"POST">>, Path, Headers).
 
--spec post(pid(), iodata(), headers(), iodata() | req_opts()) -> reference().
+-spec post(pid(), iodata(), req_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).
 
--spec post(pid(), iodata(), headers(), iodata(), req_opts()) -> reference().
+-spec post(pid(), iodata(), req_headers(), iodata(), req_opts()) -> reference().
 post(ServerPid, Path, Headers, Body, ReqOpts) ->
 	request(ServerPid, <<"POST">>, Path, Headers, Body, ReqOpts).
 
--spec put(pid(), iodata(), headers()) -> reference().
+-spec put(pid(), iodata(), req_headers()) -> reference().
 put(ServerPid, Path, Headers) ->
 	headers(ServerPid, <<"PUT">>, Path, Headers).
 
--spec put(pid(), iodata(), headers(), iodata() | req_opts()) -> reference().
+-spec put(pid(), iodata(), req_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).
 
--spec put(pid(), iodata(), headers(), iodata(), req_opts()) -> reference().
+-spec put(pid(), iodata(), req_headers(), iodata(), req_opts()) -> reference().
 put(ServerPid, Path, Headers, Body, ReqOpts) ->
 	request(ServerPid, <<"PUT">>, Path, Headers, Body, ReqOpts).
 
 %% Generic requests interface.
 
--spec headers(pid(), iodata(), iodata(), headers()) -> reference().
+-spec headers(pid(), iodata(), iodata(), req_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().
+-spec headers(pid(), iodata(), iodata(), req_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}),
+	gen_statem:cast(ServerPid, {headers, ReplyTo, StreamRef,
+		Method, Path, normalize_headers(Headers)}),
 	StreamRef.
 
--spec request(pid(), iodata(), iodata(), headers(), iodata()) -> reference().
+-spec request(pid(), iodata(), iodata(), req_headers(), iodata()) -> reference().
 request(ServerPid, Method, Path, Headers, Body) ->
 	request(ServerPid, Method, Path, Headers, Body, #{}).
 
-%% @todo Accept header names as maps.
--spec request(pid(), iodata(), iodata(), headers(), iodata(), req_opts()) -> reference().
+-spec request(pid(), iodata(), iodata(), req_headers(), iodata(), req_opts()) -> reference().
 request(ServerPid, Method, Path, Headers, Body, ReqOpts) ->
 	StreamRef = make_ref(),
 	ReplyTo = maps:get(reply_to, ReqOpts, self()),
-	gen_statem:cast(ServerPid, {request, ReplyTo, StreamRef, Method, Path, Headers, Body}),
+	gen_statem:cast(ServerPid, {request, ReplyTo, StreamRef,
+		Method, Path, normalize_headers(Headers), Body}),
 	StreamRef.
 
+normalize_headers([]) ->
+	[];
+normalize_headers([{Name, Value}|Tail]) when is_binary(Name) ->
+	[{string:lowercase(Name), Value}|normalize_headers(Tail)];
+normalize_headers([{Name, Value}|Tail]) when is_list(Name) ->
+	[{string:lowercase(unicode:characters_to_binary(Name)), Value}|normalize_headers(Tail)];
+normalize_headers([{Name, Value}|Tail]) when is_atom(Name) ->
+	[{string:lowercase(atom_to_binary(Name, latin1)), Value}|normalize_headers(Tail)];
+normalize_headers(Headers) when is_map(Headers) ->
+	normalize_headers(maps:to_list(Headers)).
+
 %% Streaming data.
 
 -spec data(pid(), reference(), fin | nofin, iodata()) -> ok.
@@ -449,11 +462,11 @@ data(ServerPid, StreamRef, IsFin, Data) ->
 connect(ServerPid, Destination) ->
 	connect(ServerPid, Destination, [], #{}).
 
--spec connect(pid(), connect_destination(), headers()) -> reference().
+-spec connect(pid(), connect_destination(), req_headers()) -> reference().
 connect(ServerPid, Destination, Headers) ->
 	connect(ServerPid, Destination, Headers, #{}).
 
--spec connect(pid(), connect_destination(), headers(), req_opts()) -> reference().
+-spec connect(pid(), connect_destination(), req_headers(), req_opts()) -> reference().
 connect(ServerPid, Destination, Headers, ReqOpts) ->
 	StreamRef = make_ref(),
 	ReplyTo = maps:get(reply_to, ReqOpts, self()),
@@ -639,13 +652,13 @@ cancel(ServerPid, StreamRef) ->
 ws_upgrade(ServerPid, Path) ->
 	ws_upgrade(ServerPid, Path, []).
 
--spec ws_upgrade(pid(), iodata(), headers()) -> reference().
+-spec ws_upgrade(pid(), iodata(), req_headers()) -> reference().
 ws_upgrade(ServerPid, Path, Headers) ->
 	StreamRef = make_ref(),
 	gen_statem:cast(ServerPid, {ws_upgrade, self(), StreamRef, Path, Headers}),
 	StreamRef.
 
--spec ws_upgrade(pid(), iodata(), headers(), ws_opts()) -> reference().
+-spec ws_upgrade(pid(), iodata(), req_headers(), ws_opts()) -> reference().
 ws_upgrade(ServerPid, Path, Headers, Opts) ->
 	ok = gun_ws:check_options(Opts),
 	StreamRef = make_ref(),