* src/odbc/ejabberd_odbc_sup.erl: make requests return a timeout if

connections to the database cannot be established (EJABS-990).
* src/odbc/ejabberd_odbc.erl: cosmetic changes.

SVN Revision: 2427

diff --git a/src/odbc/ejabberd_odbc.erl b/src/odbc/ejabberd_odbc.erl
index 01e14bdd4ed20c204a7dd6a4027ee78f9c71cd36..8c3b0e9ed83786e641740bbf43538cdb505ba171 100644 (file)
--- a/src/odbc/ejabberd_odbc.erl
+++ b/src/odbc/ejabberd_odbc.erl
@@ -58,7 +58,7 @@
 -define(PGSQL_PORT, 5432).
 -define(MYSQL_PORT, 3306).
 
--define(TRANSACTION_TIMEOUT, 60000).
+-define(TRANSACTION_TIMEOUT, 60000). % milliseconds
 -define(KEEPALIVE_TIMEOUT, 60000).
 -define(KEEPALIVE_QUERY, "SELECT 1;").
 
@@ -96,7 +96,7 @@ sql_call(Host, Msg) ->
     case get(?STATE_KEY) of
         undefined ->
             gen_server:call(ejabberd_odbc_sup:get_random_pid(Host),
-                            {sql_cmd, Msg}, ?TRANSACTION_TIMEOUT);
+                           {sql_cmd, Msg}, ?TRANSACTION_TIMEOUT);
         _State ->
             nested_op(Msg)
     end.
@@ -147,24 +147,30 @@ escape_like(C)  -> odbc_queries:escape(C).
 init([Host, StartInterval]) ->
     case ejabberd_config:get_local_option({odbc_keepalive_interval, Host}) of
        KeepaliveInterval when is_integer(KeepaliveInterval) ->
-           timer:apply_interval(KeepaliveInterval*1000, ?MODULE, keep_alive, [self()]);
+           timer:apply_interval(KeepaliveInterval*1000, ?MODULE,
+                                keep_alive, [self()]);
        undefined ->
            ok;
        _Other ->
-           ?ERROR_MSG("Wrong odbc_keepalive_interval definition '~p' for host ~p.~n", [_Other, Host])
+           ?ERROR_MSG("Wrong odbc_keepalive_interval definition '~p'"
+                      " for host ~p.~n", [_Other, Host])
     end,
     SQLServer = ejabberd_config:get_local_option({odbc_server, Host}),
     case SQLServer of
        %% Default pgsql port
        {pgsql, Server, DB, Username, Password} ->
-           pgsql_connect(Server, ?PGSQL_PORT, DB, Username, Password, StartInterval);
+           pgsql_connect(Server, ?PGSQL_PORT, DB, Username, Password,
+                         StartInterval);
        {pgsql, Server, Port, DB, Username, Password} when is_integer(Port) ->
-           pgsql_connect(Server, Port, DB, Username, Password, StartInterval);
+           pgsql_connect(Server, Port, DB, Username, Password,
+                         StartInterval);
        %% Default mysql port
        {mysql, Server, DB, Username, Password} ->
-           mysql_connect(Server, ?MYSQL_PORT, DB, Username, Password, StartInterval);
+           mysql_connect(Server, ?MYSQL_PORT, DB, Username, Password,
+                         StartInterval);
        {mysql, Server, Port, DB, Username, Password} when is_integer(Port) ->
-           mysql_connect(Server, Port, DB, Username, Password, StartInterval);
+           mysql_connect(Server, Port, DB, Username, Password,
+                         StartInterval);
        _ when is_list(SQLServer) ->
            odbc_connect(SQLServer, StartInterval)
     end.
@@ -267,7 +273,8 @@ inner_transaction(F) ->
     case get(?NESTING_KEY) of
         ?TOP_LEVEL_TXN ->
             {backtrace, T} = process_info(self(), backtrace),
-            ?ERROR_MSG("inner transaction called at outer txn level. Trace: ~s", [T]),
+            ?ERROR_MSG("inner transaction called at outer txn level. Trace: ~s",
+                      [T]),
             erlang:exit(implementation_faulty);
         _N -> ok
     end,
@@ -292,7 +299,8 @@ outer_transaction(F, NRestarts, _Reason) ->
             ok;
         _N ->
             {backtrace, T} = process_info(self(), backtrace),
-            ?ERROR_MSG("outer transaction called at inner txn level. Trace: ~s", [T]),
+            ?ERROR_MSG("outer transaction called at inner txn level. Trace: ~s",
+                      [T]),
             erlang:exit(implementation_faulty)
     end,
     sql_query_internal("begin;"),
@@ -326,7 +334,8 @@ outer_transaction(F, NRestarts, _Reason) ->
     end.
 
 execute_bloc(F) ->
-    %% We don't alter ?NESTING_KEY here as only SQL transactions alter txn nesting
+    %% We don't alter ?NESTING_KEY here as only SQL transactions alter
+    %% txn nesting
     case catch F() of
         {aborted, Reason} ->
             {aborted, Reason};
@@ -345,7 +354,8 @@ sql_query_internal(Query) ->
                   pgsql_to_odbc(pgsql:squery(State#state.db_ref, Query));
               mysql ->
                   ?DEBUG("MySQL, Send query~n~p~n", [Query]),
-                  R = mysql_to_odbc(mysql_conn:fetch(State#state.db_ref, Query, self())),
+                  R = mysql_to_odbc(mysql_conn:fetch(State#state.db_ref,
+                                                    Query, self())),
                   ?INFO_MSG("MySQL, Received result~n~p~n", [R]),
                   R
           end,
@@ -438,7 +448,8 @@ mysql_connect(Server, Port, DB, Username, Password, StartInterval) ->
             mysql_conn:fetch(Ref, ["set names 'utf8';"], self()),
            {ok, #state{db_ref = Ref, db_type = mysql}};
        {error, Reason} ->
-           ?ERROR_MSG("MySQL connection failed: ~p~nWaiting ~p seconds before retrying...~n",
+           ?ERROR_MSG("MySQL connection failed: ~p~n"
+                      "Waiting ~p seconds before retrying...~n",
                       [Reason, StartInterval div 1000]),
            %% If we can't connect we wait before retrying
            timer:sleep(StartInterval),

diff --git a/src/odbc/ejabberd_odbc_sup.erl b/src/odbc/ejabberd_odbc_sup.erl
index 5422769daccfaff961b3e1c10ce803f49b619b9e..863c444896c4e89f1462b5ec0776e8e2524d3bf0 100644 (file)
--- a/src/odbc/ejabberd_odbc_sup.erl
+++ b/src/odbc/ejabberd_odbc_sup.erl
@@ -39,6 +39,11 @@
 -define(DEFAULT_POOL_SIZE, 10).
 -define(DEFAULT_ODBC_START_INTERVAL, 30). % 30 seconds
 
+% time to wait for the supervisor to start its child before returning
+% a timeout error to the request
+-define(CONNECT_TIMEOUT, 500). % milliseconds
+
+
 start_link(Host) ->
     supervisor:start_link({local, gen_mod:get_module_proc(Host, ?MODULE)},
                          ?MODULE, [Host]).
@@ -50,19 +55,23 @@ init([Host]) ->
            undefined ->
                       ?DEFAULT_POOL_SIZE;
                   Other ->
-                      ?ERROR_MSG("Wrong odbc_pool_size definition '~p' for host ~p, default to ~p~n",
+                      ?ERROR_MSG("Wrong odbc_pool_size definition '~p' "
+                                 "for host ~p, default to ~p~n",
                                  [Other, Host, ?DEFAULT_POOL_SIZE]),
                       ?DEFAULT_POOL_SIZE
               end,
-    StartInterval = case ejabberd_config:get_local_option({odbc_start_interval, Host}) of
+    StartInterval = case ejabberd_config:get_local_option({odbc_start_interval,
+                                                          Host}) of
                        Interval when is_integer(Interval) ->
                            Interval;
                        undefined ->
                            ?DEFAULT_ODBC_START_INTERVAL;
                        _Other2 ->
-                           ?ERROR_MSG("Wrong odbc_start_interval definition '~p' for host ~p"
-                                      ", defaulting to ~p~n",
-                                      [_Other2, Host, ?DEFAULT_ODBC_START_INTERVAL]),
+                           ?ERROR_MSG("Wrong odbc_start_interval "
+                                      "definition '~p' for host ~p, "
+                                      "defaulting to ~p~n",
+                                      [_Other2, Host,
+                                       ?DEFAULT_ODBC_START_INTERVAL]),
                            ?DEFAULT_ODBC_START_INTERVAL
                    end,
     {ok, {{one_for_one, PoolSize+1, StartInterval},
@@ -78,6 +87,11 @@ init([Host]) ->
 
 get_pids(Host) ->
     Proc = gen_mod:get_module_proc(Host, ?MODULE),
+
+    % throw an exception if supervisor is not ready (i.e. if it cannot
+    % start its children, if the database is down for example)
+    sys:get_status(Proc, ?CONNECT_TIMEOUT),
+
     [Child ||
        {_Id, Child, _Type, _Modules} <- supervisor:which_children(Proc),
        Child /= undefined].