I am trying to use a queue in activemq to dequeue messages from a virtual topic. I tried sending some messages and it is showing up in the topic under "message enqueued" but it is not able to be consumed.
The virtual topic name that i created was VirtualTopic.AA and the consumer is called Consumer.client1.VirtualTopic.AA.
In the consumer.client1.VirtualTopic.AA, i can see that there is a consumer but it is just not able to dequeue messages from the virtual topic.
Anyone knows why this is happening ? Do i need to change some settings in the configuration in the xml file ?
When you publish to a virtual topic using Spring's JmsTemplate, you need to configure it for a topic by setting the pubSubDomain property to "true".
From the JmsTemplate documentation:
If you want to use dynamic destination creation, you must specify the type of JMS destination to create, using the "pubSubDomain" property. For other operations, this is not necessary. Point-to-Point (Queues) is the default domain.
And in JmsDestinationAccessor#setPubSubDomain:
pubSubDomain - "true" for the Publish/Subscribe domain (Topics), "false" for the Point-to-Point domain (Queues)
Related
I'm using ActiveMQ Artemis messaging system, and I'm testing my setup with STOMP (stomp.py).
I created an "address" on Artemis called Site.SOF.Order.Fulfillment.Submission.ActiveOmni.Topic, and attached two queues to it:
Site.SOF.Order.Fulfillment.Submission.ActiveOmni.queue (multicast)
Site.SOF.Order.Fulfillment.Submission.ActiveOmni.log.queue (multicast)
Here are the exported bindings:
<bindings>
<address-binding routing-types="ANYCAST" name="DLQ" id="2"/>
<address-binding routing-types="ANYCAST" name="ExpiryQueue" id="6"/>
<address-binding routing-types="MULTICAST" name="activemq.notifications" id="10"/>
<address-binding routing-types="MULTICAST" name="Site.SOF.Order.Fulfillment.Submission.Topic" id="92"/>
<queue-binding address="Site.SOF.Order.Fulfillment.Submission.Topic" filter-string="" name="Site.SOF.Order.Fulfillment.Submission.log.Queue" id="97" routing-type="MULTICAST"/>
<queue-binding address="DLQ" filter-string="" name="DLQ" id="4" routing-type="ANYCAST"/>
<queue-binding address="ExpiryQueue" filter-string="" name="ExpiryQueue" id="8" routing-type="ANYCAST"/>
<queue-binding address="Site.SOF.Order.Fulfillment.Submission.Topic" filter-string="" name="Site.SOF.Order.Fulfillment.Submission.ActiveOmni.Queue" id="94" routing-type="MULTICAST"/>
</bindings>
I created a user with access to Site.*
So how do I access the queues? For example, if I use the stomp.py command line tool like so:
> subscribe Site.SOF.Order.Fulfillment.Submission.ActiveOmni.queue
I get the error:
[username] does not have permission='CREATE_ADDRESS' on address Site.SOF.Order.Fulfillment.Submission.ActiveOmni.queue
So I try adding /queue/ to the front, as I've seen in the tutorials
> subscribe /queue/Site.SOF.Order.Fulfillment.Submission.ActiveOmni.queue
But I get the same error:
[username] does not have permission='CREATE_ADDRESS' on address /queue/Site.SOF.Order.Fulfillment.Submission.ActiveOmni.queue
I can send to the topic/address without trouble. The following results in a "hello" message appearing in both queues.
send Site.SOF.Order.Fulfillment.Submission.ActiveOmni.Topic "hello"
Is this a naming convention I'm missing? Or a way to specify topic vs queue? What am I missing here that's too obvious to be clearly documented?
Let me provide some background information first...
The ActiveMQ Artemis address model includes 3 main elements - addresses, queues, and routing types. These are low-level entities which are used to implement all the different semantics for all the different protocols and configurations the broker supports.
STOMP, by contrast, just supports ambiguous "destinations." The STOMP 1.2 specification says this about destinations:
A STOMP server is modelled as a set of destinations to which messages can be sent. The STOMP protocol treats destinations as opaque string and their syntax is server implementation specific. Additionally STOMP does not define what the delivery semantics of destinations should be. The delivery, or “message exchange”, semantics of destinations can vary from server to server and even from destination to destination. This allows servers to be creative with the semantics that they can support with STOMP.
In the core address model messages are sent to addresses and consumed from queues. Addresses and queues are named independently so the names that the core producer and consumer use can be different.
ActiveMQ Artemis supports both point-to-point and pub/sub semantics for STOMP destinations. You can read more about how to configure these semantics in the latest ActiveMQ Artemis STOMP documentation.
In the STOMP point-to-point use-case a message is sent to a destination and consumed from that same destination. The name that both the STOMP producer and consumer use are the same. In order to support these semantics the broker uses a core address and a core anycast queue with the same name.
In the STOMP pub/sub use-case a client creates a subscription on a destination which it can then use to receive messages sent to that destination. The name that both the STOMP subscriber and producer use are the same. In order to support these semantics the broker uses a core address and a core multicast queue with different names. The name of the core queue is generated by the broker automatically. The subscriber can then receive the messages directly from the underlying core subscription queue.
All this stuff is done behind the scenes for STOMP clients, but it's important to understand how STOMP maps to ActiveMQ Artemis' address model so you can configure things appropriately
In your case you've configured an address with 2 multicast queues and you're trying to consume from those queues. This use-case is a mix between point-to-point and pub/sub because you have statically defined queues (i.e. not queues auto-created by the broker in response to a subscriber) but the queues are multicast. These queues are like statically configured durable subscriptions. To access the queues directly you need to use their fully-qualified queue name (i.e. FQQN) from your client. The FQQN follows the pattern of <address>::<queue> so in your case you'd use either
Site.SOF.Order.Fulfillment.Submission.ActiveOmni.Topic::Site.SOF.Order.Fulfillment.Submission.ActiveOmni.queue
or
Site.SOF.Order.Fulfillment.Submission.ActiveOmni.Topic::Site.SOF.Order.Fulfillment.Submission.ActiveOmni.log.queue
Configuring multiple queues with a topic exchange and using routing key to direct the message specific queue with spring cloud streams
My requirement is example I have the queues and exchange defined as below in consumer end
spring.cloud.stream.bindings.inputA.destination=Common-Exchange
spring.cloud.stream.bindings.inputA.group=A-Queue
spring.cloud.stream.bindings.inputB.destination=Common-Exchange
spring.cloud.stream.bindings.inputB.group=B-Queue
I should be able to specify the routing key in the consumer just like
we do it in AMQP where we can pass the exchange queue and routing key
to create the binding
I should be able to set the routing key when sending the message in
producer end using MessageBuilder
channel.send(MessageBuilder.withPayload(message).build())
Of course we can use one queue and use headers to direct different type of messages but I need to know how multiple queue connected to a single exchange work with streams.
See the Rabbit binder documentation.
On the consumer side, set the bindingRoutingKey consumer binding property.
On the producer side, the the routingKeyExpression producer binding property (e.g. headers['routingKey'] and set that header as needed).
Also see Using Existing Queues/Exchanges.
I am using ActiveMQ messaging broker and I have a requirement where the producer application would want to know if the consumer application consuming on the particular destination is up or not?
How can I achieve this?
Thanks!
You should checkout Advisory messages. It's a topic you can subscribe to if you want updates on such events.
Specifically the topic: ActiveMQ.Advisory.NoConsumer.Queue should be of interest. You need to enable it broker side though using the destination policy property: sendAdvisoryIfNoConsumers.
You can do that by using java code as follows:
Destination class has a method getConsumers() which will return List of Subscriptions to that destination,and it will in turn give you consumer information, by this you can check whether your required consumer is active or not.
Good luck!
In weblogic it is possible to create a message bridge between two JMS message queues. While configuring this bridge, a message filter can be applied so that the bridge will route messages that match the filter only.
Is it possible to achieve the same with Websphere?
Specifically I'm trying to achieve this scenario.
I have one source queue on which messages are received. Each message will have a custom JMS property set up. I would like to forward the messages on the source queue, to separate queues based on the JMS property and its value. This is easily configured in WLS using message bridges with filtering. How can I do the same in WAS?
Thanks
Savio
You need to use SIB Mediation.
The WAS info center have an example called writing a routing mediation which seems like what you need.
At the bottom of the example there is a link to what to do next which also explains how to configure WAS to use that mediation.
Without writing custom code (as per your comment on Aviram's answer), it is not possible to achieve the exact same thing, but nonetheless it is possible to achieve same effect;
You say that a 'source queue' distributes messages to other 'separate queues' according to a custom JMS property. I'm assume that you have MDBs (message driven beans) configured to process messages in these separate queues.
What you can do with WebSphere is distribute messages to these MDBs directly from the 'source queue', without having to filter/distribute them to separate queues.
This is managed by using JMS Message Selectors. You can point all your MDBs to the source queue using activation specification definitions, and for each (one for each type of message) MDB, define a JMS Message Selector that matches the ones you use in WLS. This way each message is only delivered the MDB whose filter matches the message's properties. This effectively filters/distributes messages to different MDB's as in WLS.
You may read details on configuring message selectors (during development in RAD, or at/after deploy time) at infocenter. Below is a quote to give you an idea about what it look like;
messageSelector
This attribute determines the JMS message selector
that is used to select which messages the message-driven bean
receives. For example:
JMSType='car' AND color='blue' AND weight>2500
The selector string can refer to fields in the JMS message header and
fields in the message properties. Message selectors cannot reference
message body values.
For the record, we finally ended up writing our own routing algorithm within the application to ensure that messages are sent to separate queues for each client. This way we are independent of app server implementations and the integration effort is the same across app servers, viz., adding custom queues per integrating client.
In brief, We published a JMS custom property that must be set. Using a published convention, we look up for a queue and send responses to the queue. If the property is not set, a default queue is created to route all messages. If the property is set, and the queue cannot be found an exception is raised and processing halted.
This suited our purpose. Hope it helps...
In other queue managers it is possible to setup a bridge between a queue to a topic so that publishers and subscribers does not need to know that they are using a topic:
Example in TIBCO EMS
create Bridge source=queue:QName
target=topic:TName
create Bridge
source=topic:TName target=queue:QName
How do I do this in WMQ?
See WebSphere MQ V7.0 Features and Enhancements page 47, it mentions the use of Alias queues and administrative subscriptions
WebSphere MQ V7.0 introduces an
extension to the alias queue object
that allows it to be resolved to the
new topic object. This is useful for
migrating point-to-point messaging
applications to the Publish/Subscribe
model. A traditional point-to-point
application that puts messages into
WebSphere MQ can operate as a
publisher without any code changes by
utilizing an alias queue that resolves
to a topic object. This is implemented
administratively by defining a topic
object that maps to an appropriate
topic string on which the messages are
to be published. The original local
queue is deleted and replaced by an
alias queue of the same name that
resolves to the topic object. Also
note that a point-to-point application
that gets messages from WebSphere MQ
can operate as a subscriber without
any code changes by defining an
administrative subscription to a
topic.
Example 9.3 on page 220 shows how to setup a administrative subscription from a Topic to a destination queue
DEFINE SUB(SUB.RETAIL.CAT) TOPICOBJ(MATT.RETAIL.CAT) DESTCLAS(MANAGED)
DEFINE SUB(SUB.MATTRETCAT) TOPICSTR(‘matt/retail/cat’) DESTCLAS(MANAGED)
DEFINE SUB(SUB.PROVCAT) TOPICSTR(‘matt/retail/cat’) DEST(SUB.PROVCAT.DESTQ)