server/AyaNova/Program.cs

@@ -30,6 +30,9 @@ namespace AyaNova
             //Boot lock for generator
             ServerGlobalOpsSettingsCache.BOOTING = true;
 
+            //preset, we don't know yet
+            ServerGlobalOpsSettingsCache.DBAVAILABLE = false;
+
             //Get config
             var config = new ConfigurationBuilder().AddJsonFile("config.json", true).AddEnvironmentVariables().AddCommandLine(args).Build();
 

server/AyaNova/Startup.cs

@@ -142,6 +142,8 @@ namespace AyaNova
             }
 
 
+            //We have db available
+            ServerGlobalOpsSettingsCache.DBAVAILABLE = true;
 
             _newLog.LogInformation("Connected to database server - {0}", DbUtil.DisplayableConnectionString);
 

server/AyaNova/util/DbUtil.cs

@@ -202,10 +202,34 @@ namespace AyaNova.Util
                 return false;
             }
             return true;
-
         }
 
-
+        ///////////////////////////////////////////////
+        // Set global flag if db server is connectable
+        //
+        internal static void CheckDatabaseServerAvailable()
+        {
+            //Called by generator when db is down to check if it can connect
+            //should not run too quickly or too often so a delay is built in here
+            if (DateTime.UtcNow - LAST_CHECK_IF_DB_SERVER_AVAILABLE < CHECK_IF_DB_SERVER_AVAILABLE_DELAY)//no more often than every 10 seconds
+                return;
+            try
+            {
+                using (var conn = new Npgsql.NpgsqlConnection(AdminConnectionString))
+                {
+                    conn.Open();
+                    conn.Close();
+                }
+            }
+            catch
+            {
+                return;
+            }
+            //We have db available
+            ServerGlobalOpsSettingsCache.DBAVAILABLE = true;
+        }
+        private static DateTime LAST_CHECK_IF_DB_SERVER_AVAILABLE = DateTime.MinValue;
+        private static TimeSpan CHECK_IF_DB_SERVER_AVAILABLE_DELAY = new TimeSpan(0, 0, 10);
 
 
         ///////////////////////////////////////////

server/AyaNova/util/ServerGlobalOpsSettingsCache.cs

@@ -15,6 +15,10 @@ namespace AyaNova.Util
         //is used to control generator from starting
         internal static bool BOOTING { get; set; }
 
+        //False if db server is detected to be down
+        //is used to control generator from processing
+        internal static bool DBAVAILABLE { get; set; }
+
         internal static GlobalOpsBackupSettings Backup { get; set; }
         internal static GlobalOpsNotificationSettings Notify { get; set; }
         internal static DateTime NextBackup { get; set; }