mod_push_keepalive: Delay 'wake_on_start'

Delay the 'wake_on_start' notifications until ejabberd is fully
initialized.  This makes sure no s2s connections are initiated before
certificates are loaded.

Many thanks to Friedrich Altheide for reporting the issue.

src/mod_push_keepalive.erl

@@ -32,8 +32,9 @@
 -export([start/2, stop/1, reload/3, mod_opt_type/1, mod_options/1, depends/2]).
 -export([mod_doc/0]).
 %% ejabberd_hooks callbacks.
--export([c2s_session_pending/1, c2s_session_resumed/1, c2s_copy_session/2,
-	 c2s_handle_cast/2, c2s_handle_info/2, c2s_stanza/3]).
+-export([ejabberd_started/0, c2s_session_pending/1, c2s_session_resumed/1,
+	 c2s_copy_session/2, c2s_handle_cast/2, c2s_handle_info/2,
+	 c2s_stanza/3]).
 
 -include("logger.hrl").
 -include_lib("xmpp/include/xmpp.hrl").
@@ -47,28 +48,16 @@
 %% gen_mod callbacks.
 %%--------------------------------------------------------------------
 -spec start(binary(), gen_mod:opts()) -> ok.
-start(Host, Opts) ->
-    case mod_push_keepalive_opt:wake_on_start(Opts) of
-	true ->
-	    wake_all(Host);
-	false ->
-	    ok
-    end,
+start(Host, _Opts) ->
     register_hooks(Host).
 
 -spec stop(binary()) -> ok.
 stop(Host) ->
     unregister_hooks(Host).
 
 -spec reload(binary(), gen_mod:opts(), gen_mod:opts()) -> ok.
-reload(Host, NewOpts, OldOpts) ->
-    case {mod_push_keepalive_opt:wake_on_start(NewOpts),
-	  mod_push_keepalive_opt:wake_on_start(OldOpts)} of
-	{true, false} ->
-	    wake_all(Host);
-	_ ->
-	    ok
-    end.
+reload(_Host, _NewOpts, _OldOpts) ->
+    ok.
 
 -spec depends(binary(), gen_mod:opts()) -> [{module(), hard | soft}].
 depends(_Host, _Opts) ->
@@ -146,7 +135,10 @@ register_hooks(Host) ->
     ejabberd_hooks:add(c2s_handle_info, Host, ?MODULE,
 		       c2s_handle_info, 50),
     ejabberd_hooks:add(c2s_handle_send, Host, ?MODULE,
-		       c2s_stanza, 50).
+		       c2s_stanza, 50),
+    % Wait for ejabberd_pkix before running our ejabberd_started/0, so that we
+    % don't initiate s2s connections before certificates are loaded:
+    ejabberd_hooks:add(ejabberd_started, ?MODULE, ejabberd_started, 90).
 
 -spec unregister_hooks(binary()) -> ok.
 unregister_hooks(Host) ->
@@ -161,7 +153,14 @@ unregister_hooks(Host) ->
     ejabberd_hooks:delete(c2s_handle_info, Host, ?MODULE,
 			  c2s_handle_info, 50),
     ejabberd_hooks:delete(c2s_handle_send, Host, ?MODULE,
-			  c2s_stanza, 50).
+			  c2s_stanza, 50),
+    case gen_mod:is_loaded_elsewhere(Host, ?MODULE) of
+	false ->
+	    ejabberd_hooks:delete(
+	      ejabberd_started, ?MODULE, ejabberd_started, 90);
+	true ->
+	    ok
+    end.
 
 %%--------------------------------------------------------------------
 %% Hook callbacks.
@@ -233,6 +232,12 @@ c2s_handle_info(#{push_enabled := true, mgmt_state := pending,
 c2s_handle_info(State, _) ->
     State.
 
+-spec ejabberd_started() -> ok.
+ejabberd_started() ->
+    [wake_all(Host) || Host <- ejabberd_config:get_option(hosts),
+		       mod_push_keepalive_opt:wake_on_start(Host)],
+    ok.
+
 %%--------------------------------------------------------------------
 %% Internal functions.
 %%--------------------------------------------------------------------