Add options that allow to configure proxy used by rest module

src/ejabberd_option.erl

@@ -119,6 +119,10 @@
 -export([redis_server/0]).
 -export([registration_timeout/0]).
 -export([resource_conflict/0, resource_conflict/1]).
+-export([rest_proxy/0, rest_proxy/1]).
+-export([rest_proxy_password/0, rest_proxy_password/1]).
+-export([rest_proxy_port/0, rest_proxy_port/1]).
+-export([rest_proxy_username/0, rest_proxy_username/1]).
 -export([router_cache_life_time/0]).
 -export([router_cache_missed/0]).
 -export([router_cache_size/0]).
@@ -833,6 +837,34 @@ resource_conflict() ->
 resource_conflict(Host) ->
     ejabberd_config:get_option({resource_conflict, Host}).
 
+-spec rest_proxy() -> binary().
+rest_proxy() ->
+    rest_proxy(global).
+-spec rest_proxy(global | binary()) -> binary().
+rest_proxy(Host) ->
+    ejabberd_config:get_option({rest_proxy, Host}).
+
+-spec rest_proxy_password() -> string().
+rest_proxy_password() ->
+    rest_proxy_password(global).
+-spec rest_proxy_password(global | binary()) -> string().
+rest_proxy_password(Host) ->
+    ejabberd_config:get_option({rest_proxy_password, Host}).
+
+-spec rest_proxy_port() -> char().
+rest_proxy_port() ->
+    rest_proxy_port(global).
+-spec rest_proxy_port(global | binary()) -> char().
+rest_proxy_port(Host) ->
+    ejabberd_config:get_option({rest_proxy_port, Host}).
+
+-spec rest_proxy_username() -> string().
+rest_proxy_username() ->
+    rest_proxy_username(global).
+-spec rest_proxy_username(global | binary()) -> string().
+rest_proxy_username(Host) ->
+    ejabberd_config:get_option({rest_proxy_username, Host}).
+
 -spec router_cache_life_time() -> 'infinity' | pos_integer().
 router_cache_life_time() ->
     ejabberd_config:get_option({router_cache_life_time, global}).

src/ejabberd_options.erl

@@ -333,6 +333,14 @@ opt_type(registration_timeout) ->
     econf:timeout(second, infinity);
 opt_type(resource_conflict) ->
     econf:enum([setresource, closeold, closenew, acceptnew]);
+opt_type(rest_proxy) ->
+    econf:domain();
+opt_type(rest_proxy_port) ->
+    econf:port();
+opt_type(rest_proxy_username) ->
+    econf:string();
+opt_type(rest_proxy_password) ->
+    econf:string();
 opt_type(router_cache_life_time) ->
     econf:timeout(second, infinity);
 opt_type(router_cache_missed) ->
@@ -652,6 +660,10 @@ options() ->
      {redis_server, "localhost"},
      {registration_timeout, timer:seconds(600)},
      {resource_conflict, acceptnew},
+     {rest_proxy, <<>>},
+     {rest_proxy_port, 0},
+     {rest_proxy_username, ""},
+     {rest_proxy_password, ""},
      {router_cache_life_time,
       fun(Host) -> ejabberd_config:get_option({cache_life_time, Host}) end},
      {router_cache_missed,

src/ejabberd_options_doc.erl

@@ -1194,6 +1194,22 @@ doc() ->
                "uses old Jabber Non-SASL authentication (XEP-0078), "
                "then this option is not respected, and the action performed "
                "is 'closeold'.")}},
+     {rest_proxy,
+      #{value => "Host",
+        desc => ?T("Address of a HTTP Connect proxy used by modules issuing rest calls "
+                   "(like ejabberd_oauth_rest)")}},
+      {rest_proxy_port,
+       #{value => "1..65535",
+         desc => ?T("Port of a HTTP Connect proxy used by modules issuing rest calls "
+                    "(like ejabberd_oauth_rest)")}},
+      {rest_proxy_username,
+       #{value => "string()",
+         desc => ?T("Username used to authenticate to HTTP Connect proxy used by modules issuing rest calls "
+                    "(like ejabberd_oauth_rest)")}},
+      {rest_proxy_password,
+       #{value => "string()",
+         desc => ?T("Password used to authenticate to HTTP Connect proxy used by modules issuing rest calls "
+                    "(like ejabberd_oauth_rest)")}},
      {router_cache_life_time,
       #{value => "timeout()",
         desc =>

src/rest.erl

@@ -38,7 +38,14 @@
 start(Host) ->
     application:start(inets),
     Size = ejabberd_option:ext_api_http_pool_size(Host),
-    httpc:set_options([{max_sessions, Size}]).
+    Proxy = case {ejabberd_option:rest_proxy(Host),
+                  ejabberd_option:rest_proxy_port(Host)} of
+                {<<>>, _, _} ->
+                    [];
+                {Host, Port} ->
+                    [{proxy, {{binary_to_list(Host), Port}, []}}]
+            end,
+    httpc:set_options([{max_sessions, Size}] ++ Proxy).
 
 stop(_Host) ->
     ok.
@@ -87,8 +94,15 @@ request(Server, Method, Path, Params, Mime, Data) ->
 			_ -> {Params, []}
 		   end,
     URI = to_list(url(Server, Path, Query)),
-    HttpOpts = [{connect_timeout, ?CONNECT_TIMEOUT},
+    HttpOpts = case {ejabberd_option:rest_proxy_username(Server),
-		{timeout, ?HTTP_TIMEOUT}],
+                     ejabberd_option:rest_proxy_password(Server)} of
+                   {"", _} -> [{connect_timeout, ?CONNECT_TIMEOUT},
+                               {timeout, ?HTTP_TIMEOUT}];
+                   {User, Pass} ->
+                       [{connect_timeout, ?CONNECT_TIMEOUT},
+                        {timeout, ?HTTP_TIMEOUT},
+                        {proxy_auth, {User, Pass}}]
+               end,
     Hdrs = [{"connection", "keep-alive"},
             {"Accept", "application/json"},
 	    {"User-Agent", "ejabberd"}]