When sending request from 2 machines, how can both machines request to the same rabbitmq instance? All examples are on localhost.. i have no clue on how to set this up publicly..
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I have a webpage connecting to a rabbit mq broker using javascript/websockets that are exposed by a spring app deployed in tomcat. Messages are produced 1 per second by an external application and are rendered on the webpage. The javascript subscription is durable.
The issue I'm experiencing is that when the network connection is broken on the javascript client for a period of time (say 60 seconds), the first ~24 seconds of messages are missing. I've looked through the logs of the app deployed in tomcat and the missing messages seem to be up until the following log statement:
org.springframework.messaging.simp.stomp.StompBrokerRelayMessageHandler - DEBUG - TCP connection to broker closed in session 14
I think this is the point at which the endpoint realises the javascript client is disconnected and decides to close the connection to the broker resulting in future messages queueing up.
My question is how can I ensure that the messages between the time the network is severed and the time the endpoint realises the client is disconnected are not lost? Should the endpoint put the messages back on the queue somehow? Maybe there's a way to make it transactional?
Thanks in advance.
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Your Tomcat application should not acknowledge messages from RabbitMQ until it confirms that your Javascript client has received them. This way, any messages that aren't ack-ed by the JS client won't be ack-ed by Tomcat, and RabbitMQ will re-deliver them.
I don't know how your JS app and Tomcat interact, but you may have to implement your own ack process there.
I went thought NServiceBus documentation including the durable messaging one. What I understand is that when the server is offline the messages continue to go into the server's input queue which get picked up when server comes back online.
But what if the server is completely down and the input queue is not accessible?
I'm using Bus.Send from the client.
It depends on what transport you're using.
In the case of a brokered message queue, like Azure Service Bus, as long as that service is available, the fact the machine that will eventually retrieve the messages is offline is irrelevant, as that machine is simply asking the external queuing service for messages. The same goes for a transport like SQL Server.
In the case of a transport like MSMQ, which is a store a forward style queue, the messages will remain in a local outgoing queue until the remote machine becomes available.
Can you double check that you are looking in the correct spot? If you aren't getting an error out of NServiceBus when you Send, then MSMQ is installed. If it can't be reached or the service is stopped you should get errors.
The Outbound queues are in a different place as illustrated here:
http://blogs.msdn.com/cfs-filesystemfile.ashx/__key/communityserver-components-postattachments/00-09-06-31-16/outgoingempty.JPG
As RMD indicated, this is an advantage of the store and forward MSMQ transport.. the local outbound queue should just stack these up until the remote server is available.
Thx.
Joe
I have worked on IBM MQ and this is the first project where I am to work on ActiveMQ. After reading basic tutorial I found that both are similar. So I started creating small applications to listen to some queues.
Working with IBM MQ, I used to use RFHUtil tool to browse/send messages to queue which provided features to set message headers as well.
In activeMQ I am sending messages from localhost admin console. I do not find options to set message header from here. For example if I want to set source system in the message header. Is there any way/tool to get this feature on activeMQ?
I like hermes jms
Be sure to pick the Head version if you want support for headers. Its pretty similar to RFHUtil but allows "all" JMS providers.
http://hermesjms.com/patches/
I also made a command line tool for the same task which is handy, called A.
I have spent days reading MSDN, forums and article about this, and cannot find a solution to my problem.
As a PoC, I need to consume a queue from more than one machine since I need fault tolerance on the consumers side. Performance is not an issue since less than 100 messages a day should by exchanged.
I have coded two trivial console application , one as client, the other one as server. Using Framework 4.0 (tested also on 3.5). Messages are using transactions.
Everything runs fines on a single machine (Windows 7), even when running multiple consumers application instance.
Now I have a 2012 and a 2008 R2 virtual test servers running in the same domain (but don't want to use AD integration anyway). I am using IP address or "." in endpoint address attribute to prevent from DNS / AD resolution side effects.
Everything works fine IF the the queue is hosted by the consumer and the producer is submitting messages on the remote private queue. This is also true if I exchange the consumer / producer role of the 2012 and 2008 server.
But I have NEVER been able to make this run, using WCF, when the consumer is reading from remote queue and the producer is submitting messages localy. Submition never fails, my problem is on the consumer side.
My wish is to make this run using netMsmqBinding, but I also tried using msmqIntegrationBinding. For each test, I adapted code and configuration, then confirmed this was running ok when the consumer was consuming from the local queue.
The last test I have done is using WCF (msmqIntegrationBinding) only on the producer (local queue) and System.Messaging.MessageQueue on the consumer (remote queue) : It works fine ! => My goal is to make the same using WCF and netMsmqBinding on both sides.
In my point of view, I have proved this problem is a WCF issue, not an MSMQ one. This has nothing to do with security, authentication, firewall, transport, protocol, MSMQ version etc.
Errors info using MS Service Trace Viewer :
Using msmqIntegrationBinding when receiving the message (openning queue was ok) : An error occurred while receiving a message from the queue: The transaction specified cannot be imported. (-1072824242, 0xc00e004e). Ensure that MSMQ is installed and running. Make sure the queue is available to receive from.
Using netMsmqBinding, on opening the queue : An error occurred when converting the '172.22.1.9\private$\Test' queue path name to the format name: The queue path name specified is invalid. (-1072824300, 0xc00e0014). All operations on the queued channel failed. Ensure that the queue address is valid. MSMQ must be installed with Active Directory integration enabled and access to it is available.
If someone can help to find why my configuration cannot be handled by WCF, a much elegant and configurable way than Messaging, I would greatly appreciate !
Thank you.
You may need to post you consumer code and config to give more of an idea but it could be the construction of the queue name - e.g.
FormatName:DIRECT=TCP:192.168.0.2\SomeQueue
There are several different ways to connect to a queue and it changes when you are remote or local as well.
I have found this article in the past to help:
http://blogs.msdn.com/b/johnbreakwell/archive/2009/02/26/difference-between-path-name-and-format-name-when-accessing-msmq-queues.aspx
Also, MessageQueue Constructor on MSDN...
http://msdn.microsoft.com/en-us/library/ch1d814t.aspx
I have a scenario where I need a desktop console app to communicate with a Windows Azure Queue... the most important thing is that the message is received by the server eventually. Also, the desktop app may be disconnected from the Internet sometimes. In the traditional WCF+MSMQ approach you'd be able to send a message which would be cached in MSMQ until MSMQ could reach the Server's MSMQ and send the message. What's the equivalent when Windows Azure is the server-side?
Is it possible for the same approach to be used, where MSMQ just communicates with a Windows Azure Queue rather than an MSMQ on a Windows Server?
Maybe Windows Azure Queue is the wrong approach? I have heard about something called message buffer, but don't know what this is (yet!).
thanks for your help
Kris
You could write an MSMQ listener service that finishes moving the message to the Azure queue when the connection to the internet has been reestablished. I don't think this would be too difficult.
Update
Perhaps my answer wasnt clear. Based on the question the client is occasionally connected to the internet so you need a way to park the message until the intertubes get untangled. Using Windows the easiest way to do this is to put the message in an MSMQ local queue. YOu then have a service monitoring that queue. If there is a message and it can get to the service hosted in the cloud it sends the message. Once the message has been sent it can be deleted from the queue.
In order to queue a message to Azure Queue Storage you have to be connected to the Internet. If you want to handle disconnected scenarios, that is totally up to you. I would keep the solution very simple and use a local storage such as SQL Server Compact and then send the messages as soon as there's connectivity, maybe with the aid of a Windows Service (so that you don't need to run the desktop app).
You can do this with the Azure AppFabric Service Bus Message Buffers - there is no need to use a Queue. Check out the related sample downloads on the following site: http://www.idesign.net/idesign/DesktopDefault.aspx?tabindex=5&tabid=11 - they should answer your questions much better than I can.
Regards