refactor: log topology and increase reconnect interval

Author: karenc-bq

wrapper/src/main/java/com/amazon/awslabs/jdbc/hostlistprovider/AuroraHostListProvider.java

@@ -186,14 +186,17 @@ public List<HostSpec> getTopology(final Connection conn, final boolean forceUpda
         || refreshNeeded(clusterTopologyInfo)) {
 
       final ClusterTopologyInfo latestTopologyInfo = queryForTopology(conn);
-
+      List<HostSpec> hosts;
       if (!latestTopologyInfo.hosts.isEmpty()) {
         clusterTopologyInfo = updateCache(clusterTopologyInfo, latestTopologyInfo);
+        hosts = clusterTopologyInfo.hosts;
       } else {
-        return (clusterTopologyInfo == null || forceUpdate)
+        hosts = (clusterTopologyInfo == null || forceUpdate)
             ? new ArrayList<>()
             : clusterTopologyInfo.hosts;
       }
+      logTopology(hosts);
+      return hosts;
     }
 
     return clusterTopologyInfo.hosts;
@@ -536,6 +539,19 @@ private void validateHostPatternSetting(String hostPattern) {
     }
   }
 
+  private void logTopology(final List<HostSpec> topology) {
+    StringBuilder msg = new StringBuilder();
+    for (int i = 0; i < topology.size(); i++) {
+      HostSpec hostInfo = topology.get(i);
+      msg.append("\n   [")
+          .append(i)
+          .append("]: ")
+          .append(hostInfo == null ? "<null>" : hostInfo.getHost());
+    }
+    LOGGER.finer(
+        Messages.get("Failover.topologyObtained", new Object[] {msg.toString()}));
+  }
+
   /**
    * Class that holds the topology and additional information about the topology.
    */

wrapper/src/main/java/com/amazon/awslabs/jdbc/plugin/failover/ClusterAwareReaderFailoverHandler.java

@@ -294,7 +294,7 @@ private ReaderFailoverResult getConnectionFromHostGroup(List<HostTuple> hostGrou
         }
 
         try {
-          TimeUnit.MILLISECONDS.sleep(1);
+          TimeUnit.SECONDS.sleep(1);
         } catch (InterruptedException e) {
           Thread.currentThread().interrupt();
           throw new SQLException(Messages.get("ClusterAwareReaderFailoverHandler.1"), "70100", e);

wrapper/src/main/java/com/amazon/awslabs/jdbc/plugin/failover/ClusterAwareWriterFailoverHandler.java

@@ -343,7 +343,7 @@ private void connectToReader() throws InterruptedException {
           // ignore
         }
         LOGGER.fine(Messages.get("ClusterAwareWriterFailoverHandler.12"));
-        TimeUnit.MILLISECONDS.sleep(1);
+        TimeUnit.SECONDS.sleep(1);
       }
     }
 

wrapper/src/main/java/com/amazon/awslabs/jdbc/plugin/failover/FailoverConnectionPlugin.java

@@ -170,19 +170,6 @@ public <T, E extends Exception> T execute(
       return jdbcMethodFunc.call();
     }
 
-    try {
-      final RdsUrlType type = this.getHostListProvider().getRdsUrlType();
-      if (type.isRdsCluster()) {
-        this.explicitlyReadOnly = (type == RdsUrlType.RDS_READER_CLUSTER);
-        LOGGER.finer(
-            Messages.get(
-                "Failover.parameterValue",
-                new Object[] {"explicitlyReadOnly", this.explicitlyReadOnly}));
-      }
-    } catch (SQLException ex) {
-      throw wrapExceptionIfNeeded(exceptionClass, ex);
-    }
-
     if (this.isClosed && !allowedOnClosedConnection(methodName)) {
       try {
         invalidInvocationOnClosedConnection();
@@ -267,6 +254,15 @@ void initHostProvider(
     this.writerFailoverHandler = writerFailoverHandlerSupplier.apply(hostListProvider);
 
     initHostProviderFunc.call();
+
+    final RdsUrlType type = this.getHostListProvider().getRdsUrlType();
+    if (type.isRdsCluster()) {
+      this.explicitlyReadOnly = (type == RdsUrlType.RDS_READER_CLUSTER);
+      LOGGER.finer(
+          Messages.get(
+              "Failover.parameterValue",
+              new Object[] {"explicitlyReadOnly", this.explicitlyReadOnly}));
+    }
   }
 
   private AuroraHostListProvider getHostListProvider() throws SQLException {
@@ -345,7 +341,7 @@ private void invalidInvocationOnClosedConnection() throws SQLException {
       pickNewConnection();
 
       // "The active SQL connection has changed. Please re-configure session state if required."
-      LOGGER.severe(Messages.get("Failover.connectionChangedError"));
+      LOGGER.info(Messages.get("Failover.connectionChangedError"));
       throw new SQLException(
           Messages.get("Failover.connectionChangedError"),
           SqlState.COMMUNICATION_LINK_CHANGED.getState());
@@ -652,7 +648,7 @@ protected synchronized void failover(final HostSpec failedHost) throws SQLExcept
       // "Transaction resolution unknown. Please re-configure session state if required and try
       // restarting transaction."
       final String errorMessage = Messages.get("Failover.transactionResolutionUnknownError");
-      LOGGER.severe(errorMessage);
+      LOGGER.info(errorMessage);
       throw new SQLException(errorMessage, SqlState.CONNECTION_FAILURE_DURING_TRANSACTION.getState());
     } else {
       // "The active SQL connection has changed due to a connection failure. Please re-configure