Make get_backend helper use HostType

Because backends can be running per host type. This also fixes an
issue of suites logging that they finished dirty, after having
dynamically compiled backends removed.

The old interface is called for the time being, but will be removed when
all modules will have dynamic backends converted.

big_tests/tests/mongoose_helper.erl

@@ -6,7 +6,7 @@
 
 -export([is_rdbms_enabled/1,
          mnesia_or_rdbms_backend/0,
-         get_backend_name/1]).
+         get_backend_name/2]).
 
 -export([auth_modules/0]).
 
@@ -141,13 +141,30 @@ new_mongoose_acc(Location, Server) ->
 clear_caps_cache(CapsNode) ->
     ok = rpc(mim(), mod_caps, delete_caps, [CapsNode]).
 
-get_backend(Module) ->
-  case rpc(mim(), Module, backend, []) of
-    {badrpc, _Reason} -> false;
-    Backend -> Backend
-  end.
+get_backend(HostType, Module) ->
+    try rpc(mim(), mongoose_backend, get_backend_module, [HostType, Module])
+    catch
+        error:{badrpc, _Reason} ->
+            % TODO: get rid of this after dynamically compiled modules are gone
+            get_backend_old(Module)
+    end.
+
+get_backend_name(HostType, Module) ->
+    try rpc(mim(), mongoose_backend, get_backend_name, [HostType, Module])
+    catch
+        error:{badrpc, _Reason} ->
+            % TODO: get rid of this after dynamically compiled modules are gone
+            % used by offline_SUITE
+            get_backend_name_old(Module)
+    end.
+
+get_backend_old(Module) ->
+    case rpc(mim(), Module, backend, []) of
+        {badrpc, _Reason} -> false;
+        Backend -> Backend
+    end.
 
-get_backend_name(Module) ->
+get_backend_name_old(Module) ->
     case rpc(mim(), Module, backend_name, []) of
         {badrpc, _Reason} -> false;
         Backend -> Backend
@@ -158,9 +175,12 @@ generic_count(mod_offline_backend, {LUser, LServer}) ->
     rpc(mim(), mod_offline_backend, count_offline_messages, [HostType, LUser, LServer, 100]).
 
 generic_count(Module) ->
-    case get_backend(Module) of
+    lists:sum([generic_count_per_host_type(HT, Module) || HT <- domain_helper:host_types()]).
+
+generic_count_per_host_type(HostType, Module) ->
+    case get_backend(HostType, Module) of
         false -> %% module disabled
-            false;
+            0;
         B when is_atom(B) ->
             generic_count_backend(B)
     end.

big_tests/tests/offline_SUITE.erl

@@ -74,7 +74,7 @@ init_per_group(chatmarkers, C) ->
 init_per_group(_, C) -> C.
 
 with_groupchat_modules() ->
-    OfflineBackend = mongoose_helper:get_backend_name(mod_offline_backend),
+    OfflineBackend = mongoose_helper:get_backend_name(host_type(), mod_offline_backend),
     MucLightBackend = mongoose_helper:mnesia_or_rdbms_backend(),
     MucPattern = distributed_helper:subhost_pattern(muc_light_helper:muc_host_pattern()),
     [{mod_offline, [{store_groupchat_messages, true},