Added functions for shard runtime updating.

server/modules/include/dbshard.h

@@ -298,6 +298,8 @@ typedef struct router_instance {
         struct router_instance* next;        /*< Next router on the list            */
 	bool			available_slaves; /*< The router has some slaves available */
 	HASHTABLE* dbnames_hash; /** Hashtable containing the database names and where to find them */
+	char** ignore_list;
+	bool update_hash;
 } ROUTER_INSTANCE;
 
 #define BACKEND_TYPE(b) (SERVER_IS_MASTER((b)->backend_server) ? BE_MASTER :    \

server/modules/routing/dbshard/dbshard.c

@@ -124,6 +124,8 @@ static prep_stmt_t* prep_stmt_init(prep_stmt_type_t type, void* id);
 static void         prep_stmt_done(prep_stmt_t* pstmt);
 #endif /*< PREP_STMT_CACHING */
 
+bool parse_db_ignore_list(ROUTER_INSTANCE* router,char* param);
+
 int bref_cmp_global_conn(
         const void* bref1,
         const void* bref2);
@@ -433,9 +435,9 @@ bool update_dbnames_hash(BACKEND** backends, HASHTABLE* hashtable)
 			lengths = mysql_fetch_lengths(result);
 
 			/**
-			 * Default databases to ignore
+			 * Default databases to ignore, disable for now
 			 */
-
+#ifdef NO_DEFAULT_DATABASES
 			if(strncmp(row[0],"information_schema",lengths[0]) == 0 ||
 			   strncmp(row[0],"performance_schema",lengths[0]) == 0 ||
 			   strncmp(row[0],"mysql",lengths[0]) == 0 ||
@@ -443,6 +445,7 @@ bool update_dbnames_hash(BACKEND** backends, HASHTABLE* hashtable)
 			   strncmp(row[0],"test",lengths[0]) == 0){
 				continue;
 			}
+#endif
 			dbnm = (char*)calloc(lengths[0] + 1,sizeof(char));
 			memcpy(dbnm,row[0],lengths[0]);
 			servnm = strdup(server->unique_name);
@@ -450,51 +453,9 @@ bool update_dbnames_hash(BACKEND** backends, HASHTABLE* hashtable)
 			if(hashtable_add(hashtable,dbnm,servnm) == 0)
 			{
 				char* srvname;
-#ifdef SHARD_UPDATES			
-				{
-					char* old_backend = (char*)hashtable_fetch(hashtable,dbnm);
-					int j;
-					bool is_alive = false;
 
-					for(j = 0;backends[j];j++)
-					{
-						/**
-						 * See if the old backend is still
-						 * alive. If not then update
-						 * the hashtable with the current backend's name.
-						 */
-						if(strcmp(server->unique_name,old_backend) == 0 && 
-						   SERVER_IS_RUNNING(server))
-						{
-							is_alive = true;
-						}
-					}
-					
-					if(!is_alive)
-					{
-						hashtable_delete(hashtable,dbnm);
-					
-						if(hashtable_add(hashtable,dbnm,servnm))
-						{
-							LOGIF(LT, (skygw_log_write_flush(
-									LOGFILE_TRACE,
-									"Updated the backend of database '%s' to '%s'.",
-									dbnm,
-									servnm)));
-						}
-						else
-						{
-							LOGIF(LE, (skygw_log_write_flush(
-									LOGFILE_ERROR,
-									"Error: failed to insert values into hashtable.")));
-						}
-					}
-					goto cleanup;
-				}
-#endif /*< SHARD_UPDATES */
-				/*Check if the failure was due to a duplicate value*/
 				if((srvname = hashtable_fetch(hashtable,dbnm)) == NULL)
-				{
+			    {
 					LOGIF(LE, (skygw_log_write_flush(
 							LOGFILE_ERROR,
 							"Error: failed to insert values into hashtable.")));
@@ -503,7 +464,7 @@ bool update_dbnames_hash(BACKEND** backends, HASHTABLE* hashtable)
 				{
 					LOGIF(LE, (skygw_log_write_flush(
 							LOGFILE_ERROR,
-							"Error : conflicting "
+							"Warning : conflicting "
 							"databases found. "
 							"Both \"%s\" and \"%s\" "
 							"have a database \"%s\".",
@@ -511,11 +472,48 @@ bool update_dbnames_hash(BACKEND** backends, HASHTABLE* hashtable)
 							srvname,
 							dbnm)));
 				}
-				rval = false;
+				
-				free(dbnm);
+				char* old_backend = (char*)hashtable_fetch(hashtable,dbnm);
-				free(servnm);					
+				int j;
+				bool is_alive = false;
+
+				for(j = 0;backends[j];j++)
+				{
+					/**
+					 * See if the old backend is still
+					 * alive. If not then update
+					 * the hashtable with the current backend's name.
+					 */
+					if(strcmp(server->unique_name,old_backend) == 0 && 
+					   SERVER_IS_RUNNING(server))
+					{
+						is_alive = true;
+						break;
+					}
+				}
+					
+				if(!is_alive)
+				{
+					hashtable_delete(hashtable,dbnm);
+					
+					if(hashtable_add(hashtable,dbnm,servnm))
+					{
+						LOGIF(LT, (skygw_log_write_flush(
+									LOGFILE_TRACE,
+									"Updated the backend of database '%s' to '%s'.",
+									dbnm,
+									servnm)));
+					}
+					else
+					{
+						LOGIF(LE, (skygw_log_write_flush(
+									LOGFILE_ERROR,
+									"Error: failed to insert values into hashtable.")));
+					}
+				}
 			} /*< hashtable_add failed */
 		} /*< while */
+
 cleanup:		
 		if(result)
 		{
@@ -760,6 +758,8 @@ createInstance(SERVICE *service, char **options)
 {
         ROUTER_INSTANCE*    router;
         SERVER*             server;
+		//CONFIG_PARAMETER*  conf;
+		//char*			    confval = NULL;
         int                 nservers;
         int                 i;
         
@@ -826,11 +826,30 @@ createInstance(SERVICE *service, char **options)
 	 */
 	router->bitmask = 0;
 	router->bitvalue = 0;
+
+
+	/* Ignored for now
+	conf = config_get_param(service->svc_config_param,"ignore_databases");
+	if(conf)
+	{
+		confval = conf->value;
+	}
+	
+    if(!parse_db_ignore_list(router,confval))
+    {
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : Parsing of database ignore list failed. ")));
+		goto clean_up;
+	}
+	*/
+
 	/**
 	 * Read config version number from service to inform what configuration 
 	 * is used if any.
 	 */
         router->dbshard_version = service->svc_config_version;
+
 	/** refreshInstance(router, NULL); */
 	/**
 	 * Get hashtable which includes dbname,backend pairs
@@ -1724,7 +1743,7 @@ static int routeQuery(
 
         if (packet_type == MYSQL_COM_INIT_DB)
 	{
-		if (!change_current_db(instance, router_cli_ses, querybuf))
+		if (!change_current_db(inst, router_cli_ses, querybuf))
 		{
 			LOGIF(LE, (skygw_log_write_flush(
 				LOGFILE_ERROR,
@@ -1833,8 +1852,14 @@ static int routeQuery(
          */
 
 	/**
-	 * Added for simple sharding, using hints for testing.
+	 * Update the hashtable
 	 */
+
+	if(inst->update_hash)
+    {
+		update_dbnames_hash(inst->servers,inst->dbnames_hash);
+	}
+
 	if((tname = get_shard_target_name(inst,router_cli_ses,querybuf)) != NULL)
 	{
 			route_target = TARGET_NAMED_SERVER;
@@ -1887,6 +1912,7 @@ static int routeQuery(
 		 * Search backend server by name or replication lag. 
 		 * If it fails, then try to find valid slave or master.
 		 */ 
+
 		succp = get_shard_dcb(&target_dcb, router_cli_ses, tname);
 
 		if (!succp)
@@ -4210,4 +4236,66 @@ reply_error:
 	}
 retblock:
 	return succp;
-}
+}
+/**
+ * Parses the configuration for databases to ignore.
+ * @param router The router instance
+ * @param param Configuration parameters
+ * @return True if the parsing was successful and false if an error occurred.
+ */
+bool parse_db_ignore_list(ROUTER_INSTANCE* router, char* param)
+{
+	char** list = router->ignore_list;
+	int count = 0, i = 0;
+	char *value = param, *tok;
+	char **saveptr = NULL,**tmp;
+
+	list = malloc(sizeof(char*));
+
+	if(list == NULL){
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : malloc returned NULL.")));
+		return false;
+	}
+
+	if(param == NULL)
+	{
+		list[0] = NULL;
+		return true;
+	}
+
+	/**We have at least one value to ignore*/
+
+	count++;
+
+	tok = value;
+
+	while((tok = strchr(tok,',')))
+	{
+		tok++;
+		count++;
+	}
+
+    tmp = realloc(list,(count + 1)*sizeof(char*));
+	tok = strtok_r(value,",",saveptr);
+	
+	if(tmp == NULL)
+	{
+		LOGIF(LE, (skygw_log_write_flush(
+			LOGFILE_ERROR,
+			"Error : realloc returned NULL.")));
+		return false;
+	}
+
+	list = tmp;
+
+	while(tok && count > i)
+	{
+		list[i++] = strdup(tok);
+		tok = strtok_r(NULL,",",saveptr);
+	}
+
+	list[i] = NULL;
+	return true;
+}