From 6e838af88027d06b239d346b4617db24b6e8e830 Mon Sep 17 00:00:00 2001
From: "K.V Suneelu Verma" <k.v.suneelu.verma@ericsson.com>
Date: Tue, 16 Aug 2016 22:53:48 +0530
Subject: [PATCH] Bug 5555: Exception during operations on ReadWriteTransaction

An IllegalStateException can be happened during operations on
ReadWriteTransaction. This was resulting in system not being able to
process any southbound ovsdb events, since the code didn't handle this
exception.

Change-Id: I24ab3acc01fd5fb4d9380ccc8bcc7d332738d242
Signed-off-by: K.V Suneelu Verma <k.v.suneelu.verma@ericsson.com>
---
 .../md/TransactionInvokerImpl.java            | 23 ++++++++++++++++---
 .../md/TransactionInvokerImpl.java            | 23 ++++++++++++++++---
 2 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/hwvtepsouthbound/hwvtepsouthbound-impl/src/main/java/org/opendaylight/ovsdb/hwvtepsouthbound/transactions/md/TransactionInvokerImpl.java b/hwvtepsouthbound/hwvtepsouthbound-impl/src/main/java/org/opendaylight/ovsdb/hwvtepsouthbound/transactions/md/TransactionInvokerImpl.java
index 8f4ab7005..6be19c89e 100644
--- a/hwvtepsouthbound/hwvtepsouthbound-impl/src/main/java/org/opendaylight/ovsdb/hwvtepsouthbound/transactions/md/TransactionInvokerImpl.java
+++ b/hwvtepsouthbound/hwvtepsouthbound-impl/src/main/java/org/opendaylight/ovsdb/hwvtepsouthbound/transactions/md/TransactionInvokerImpl.java
@@ -80,10 +80,20 @@ public class TransactionInvokerImpl implements TransactionInvoker,TransactionCha
     public void run() {
         while (true) {
             forgetSuccessfulTransactions();
+
+            List<TransactionCommand> commands = null;
+            try {
+                commands = extractCommands();
+            } catch (InterruptedException e) {
+                LOG.warn("Extracting commands was interrupted.", e);
+                continue;
+            }
+
+            ReadWriteTransaction transactionInFlight = null;
             try {
-                List<TransactionCommand> commands = extractCommands();
                 for (TransactionCommand command: commands) {
                     final ReadWriteTransaction transaction = chain.newReadWriteTransaction();
+                    transactionInFlight = transaction;
                     recordPendingTransaction(command, transaction);
                     command.execute(transaction);
                     Futures.addCallback(transaction.submit(), new FutureCallback<Void>() {
@@ -98,8 +108,15 @@ public class TransactionInvokerImpl implements TransactionInvoker,TransactionCha
                         }
                     });
                 }
-            } catch (Exception e) {
-                LOG.warn("Exception invoking Transaction: ", e);
+            } catch (IllegalStateException e) {
+                if (transactionInFlight != null) {
+                    // TODO: This method should distinguish exceptions on which the command should be
+                    // retried from exceptions on which the command should NOT be retried.
+                    // Then it should retry only the commands which should be retried, otherwise
+                    // this method will retry commands which will never be successful forever.
+                    failedTransactionQueue.offer(transactionInFlight);
+                }
+                LOG.warn("Failed to process an update notification from OVS.", e);
             }
         }
     }
diff --git a/southbound/southbound-impl/src/main/java/org/opendaylight/ovsdb/southbound/transactions/md/TransactionInvokerImpl.java b/southbound/southbound-impl/src/main/java/org/opendaylight/ovsdb/southbound/transactions/md/TransactionInvokerImpl.java
index ae8ea401a..66b589efb 100644
--- a/southbound/southbound-impl/src/main/java/org/opendaylight/ovsdb/southbound/transactions/md/TransactionInvokerImpl.java
+++ b/southbound/southbound-impl/src/main/java/org/opendaylight/ovsdb/southbound/transactions/md/TransactionInvokerImpl.java
@@ -77,10 +77,20 @@ public class TransactionInvokerImpl implements TransactionInvoker,TransactionCha
     public void run() {
         while (runTask.get()) {
             forgetSuccessfulTransactions();
+
+            List<TransactionCommand> commands = null;
+            try {
+                commands = extractCommands();
+            } catch (InterruptedException e) {
+                LOG.warn("Extracting commands was interrupted.", e);
+                continue;
+            }
+
+            ReadWriteTransaction transactionInFlight = null;
             try {
-                List<TransactionCommand> commands = extractCommands();
                 for (TransactionCommand command: commands) {
                     final ReadWriteTransaction transaction = chain.newReadWriteTransaction();
+                    transactionInFlight = transaction;
                     recordPendingTransaction(command, transaction);
                     command.execute(transaction);
                     Futures.addCallback(transaction.submit(), new FutureCallback<Void>() {
@@ -95,8 +105,15 @@ public class TransactionInvokerImpl implements TransactionInvoker,TransactionCha
                         }
                     });
                 }
-            } catch (InterruptedException e) {
-                LOG.warn("Exception invoking Transaction: ", e);
+            } catch (IllegalStateException e) {
+                if (transactionInFlight != null) {
+                    // TODO: This method should distinguish exceptions on which the command should be
+                    // retried from exceptions on which the command should NOT be retried.
+                    // Then it should retry only the commands which should be retried, otherwise
+                    // this method will retry commands which will never be successful forever.
+                    failedTransactionQueue.offer(transactionInFlight);
+                }
+                LOG.warn("Failed to process an update notification from OVS.", e);
             }
         }
     }
-- 
2.36.6