Thanks Ralph. Let me take a look at the code.  

--  
Hari Shreedharan


On Friday, August 31, 2012 at 9:38 AM, Ralph Goers wrote:

> Which file? The files from the FileChannel, the source or …? If you want the 
> FileChannel stuff, unfortunately it only is failing on the machine where Gump 
> runs and I don't have a clue how to get access to it or if it is even left 
> around after the run. As I said, I've never had this fail on the Mac(s), my 
> Linux system or in Jenkins. I have no idea what is peculiar about that system 
> but I do know the tests take about twice as long as they do on my Mac.
>  
> If you want to look at the actual unit test source, it is at 
> https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk/flume-ng/src/test/java/org/apache/logging/log4j/flume/appender/FlumeEmbeddedAppenderTest.java
>  
> Ralph
>  
>  
>  
> On Aug 31, 2012, at 12:15 AM, Hari Shreedharan wrote:
>  
> > It looks like the channel has already got the events before the source 
> > stops. Can you send me a link to the actual file, so I can take a look?  
> >  
> >  
> > Hari  
> >  
> > --  
> > Hari Shreedharan
> >  
> >  
> > On Thursday, August 30, 2012 at 9:44 AM, Ralph Goers wrote:
> >  
> > > Thanks Hari,
> > >  
> > > First, remember that the Flume agent is embedded in the Appender. So the 
> > > Log4j EventSource is passing the event to the FileChannel. The Avro Sink 
> > > then reads from the channel and sends it on. The unit test has two Avro 
> > > Sources listening with each associated with its own MemoryChannel. The 
> > > test logs 10 events then reads the 10 events from the primary 
> > > MemoryChannel, each within its own transaction. The test then stops the 
> > > primary source. Then it logs 10 more events and tries to read them from 
> > > the alternate MemoryChannel.  
> > >  
> > >  
> > > The code to read from the channel looks like:
> > >  
> > > for (int i = 0; i < 10; ++i) {
> > > StructuredDataMessage msg = new StructuredDataMessage("Test", "Test 
> > > Primary " + i, "Test");
> > > EventLogger.logEvent(msg);
> > > }  
> > > for (int i = 0; i < 10; ++i) {
> > > Transaction transaction = primaryChannel.getTransaction();
> > > transaction.begin();
> > >  
> > > Event event = primaryChannel.take();
> > > Assert.assertNotNull(event);
> > > String body = getBody(event);
> > > String expected = "Test Primary " + i;
> > > Assert.assertTrue("Channel contained event, but not expected message. 
> > > Received: " + body,
> > > body.endsWith(expected));
> > > transaction.commit();
> > > transaction.close();
> > > }
> > >  
> > > primarySource.stop();
> > >  
> > >  
> > > for (int i = 0; i < 10; ++i) {
> > > StructuredDataMessage msg = new StructuredDataMessage("Test", "Test 
> > > Alternate " + i, "Test");
> > > EventLogger.logEvent(msg);
> > > }
> > > for (int i = 0; i < 10; ++i) {
> > > Transaction transaction = alternateChannel.getTransaction();
> > > transaction.begin();
> > >  
> > > Event event = alternateChannel.take();
> > > Assert.assertNotNull(event);
> > > String body = getBody(event);
> > > String expected = "Test Alternate " + i;
> > > /* When running in Gump Flume consistently returns the last event from 
> > > the primary channel after
> > > the failover, which fails this test */
> > > Assert.assertTrue("Channel contained event, but not expected message. 
> > > Expected: " + expected +
> > > " Received: " + body, body.endsWith(expected));
> > > transaction.commit();
> > > transaction.close();
> > > }
> > > When I run this on my Mac it never fails. But Gump fails almost every 
> > > time returning "Channel contained event, but not expected message. 
> > > Expected: Test Alternate 0 Received: <128>1 2012-08-30T05:50:04.143Z 
> > > vmgump MyApp - Test [Test@18060][mdc@18060] Test Primary 9"
> > >  
> > > Do we have any tests that are similar to this? I didn't see anything that 
> > > tests failover in this way but I might have missed it.
> > >  
> > > Ralph
> > >  
> > > On Aug 30, 2012, at 9:22 AM, Hari Shreedharan wrote:
> > >  
> > > > Hi Ralph,  
> > > >  
> > > > Sorry missed this message earlier. How are you simulating failover in 
> > > > your test - I did not look at your code. If the message was written by 
> > > > the Avro Source on the client and the Avro Sink on the other side 
> > > > simply did not get a success would cause the failover sink processor to 
> > > > retry the same message since it would be rolled back by the sink, and 
> > > > hence the channel will end up making it available for another sink. 
> > > > Generally, if a message is not ack-ed as being successfully written to 
> > > > the channel by the Avro Source, the sink will rollback the transaction 
> > > > - and throw an EventDeliveryException - and in case of Failover 
> > > > SinkProcessor, it will cause the next sink to pick it up.  
> > > >  
> > > > Also, note that Flume guarantees at least once semantics and weak 
> > > > ordering. If a failure happens, it is possible that there will be 
> > > > duplicates.  
> > > >  
> > > > And no, this is not related to any of the FileChannel issues we have 
> > > > been fixing.  
> > > >  
> > > > Thanks,
> > > > Hari
> > > >  
> > > > --  
> > > > Hari Shreedharan
> > > >  
> > > >  
> > > > On Thursday, August 30, 2012 at 7:50 AM, Ralph Goers wrote:
> > > >  
> > > > > I'm going to try again. Does this problem sound familiar to anyone?  
> > > > >  
> > > > > Ralph
> > > > >  
> > > > > On Aug 27, 2012, at 3:36 PM, Ralph Goers wrote:
> > > > >  
> > > > > > Does anyone have any thoughts on this? Is it possibly related to 
> > > > > > any of the issues already being fixed on the FileChannel?
> > > > > >  
> > > > > > Ralph
> > > > > >  
> > > > > > On Aug 26, 2012, at 4:05 PM, Ralph Goers wrote:
> > > > > >  
> > > > > > > I have successfully embedded Flume into the Log4j 2 Appender. 
> > > > > > > However, I have a unit test that has Flume fail over from one 
> > > > > > > AvroSink to another. When this happens under some circumstances I 
> > > > > > > am getting the last message successfully delivered to the first 
> > > > > > > source as the first message to the second source, which doesn't 
> > > > > > > seem correct. The unit test is 
> > > > > > > athttps://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk/flume-ng/src/test/java/org/apache/logging/log4j/flume/appender/FlumeEmbeddedAppenderTest.java
> > > > > > >  
> > > > > > > (http://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk/flume-ng/src/test/java/org/apache/logging/log4j/flume/appender/FlumeEmbeddedAppenderTest.java).
> > > > > > >  The odd thing is that I cannot get this to fail on my local 
> > > > > > > machine - it only fails when Gump runs it, but it fail fairly 
> > > > > > > consistently.
> > > > > > >  
> > > > > > > The unit test has the AppenderSource connect to a FileChannel. 
> > > > > > > Two AvroSinks are connected to the FileChannel via the Failover 
> > > > > > > processor.
> > > > > > >  
> > > > > > > Is this a known behavior?
> > > > > > >  
> > > > > > > Ralph  


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