I would like to subscribe to activemq topic using camel. Can anyone share the route configuration or example for doing the same.
My requirement is whenever a new data is published on the topic I want to push the content to database using ibatis.
thanks
Lokesh
You do the normal setup of the jms component and use the following at the start of your route:
So the key is to write jms:topic: instead of jms:. This tells camel that the name after the colon is a topic name instead of a queue name. This make camel install a listener for the topic. So for every message sent to the topic your route is called.
Related
I am integrating a NestJS application with RabbitMQ and i followed this tutorial
From the tutorial i can see that message consumer can connect to the rabbitMQ broker using a queue name, but actually i want to create a temporary queue that connects to an exchange. I cannot find an option to specify the exchange name in the queue options specified in the tutorial. can someone please point to the right configuration to use to specify an exchange instead of queue?
is it possible to specify an exchange name inside the 'queueOptions' structure?
From what I understand from your tutorial (I don't know NestJS), createMicroservice only connects to a queue (or create it if needed). In other words, it performs assertQueue operation:
var queue = 'task_queue';
channel.assertQueue(queue, {
durable: false
});
If you want to bind a queue to an existing exchange, you need to perform bindQueue operation:
channel.bindQueue(queue, exchange, '');
Thus you can't bind to an exchange using queueOptions. Take a look at the official Rabbitmq documentation, especially the "Temporary queues" and following "Bindings" sections.
I am very new to messaging and rabbitmq and trying to setup bindings in rabbitmq control panel to support the following scenario (pardon the pseudo):
queue named one
queue named two
I would like to send message destined:
only for one
only for two
for both one and two
Currently rabbitmq setup looks like this:
to: one; routing: one;
to: two; routing: two
When I publish a message I use this kind of setup:
routing key: one -> message is delivered to one;
routing key: two -> message is delivered to two;
With what routing key value do I publish a message so that both queues receive it? Or how do I setup my bindings.
You can set up wild card characters for your routing keys.
You could do routing_key: 'all', routing_key: 'all.one'or routing_key: 'all.two'
Obviously the example is contrived and you would choose more meaningful routing key names like "logging.telegraf" or "logging.events"or "weather.houston" etc. Basically you can set up something of a hierarchy using dotted notation.
Hope that helps.
Check out the official docs on topics and the use of * or #
http://www.rabbitmq.com/tutorials/tutorial-five-ruby.html
I want to use RabbitMQ with StormCrawler. I already saw that there is a repository for using RabbitMQ with Storm:
https://github.com/ppat/storm-rabbitmq
How would you use this for the StormCrawler? I would like to use the Producer as well as the consumer.
For the consumer there seems to be some documentation. What about the Producer? Can you just put the config entries in the storm crawler config or would I need to change the source code of the RabbitMQProducer?
You'd want the bolt which sends URLs to RabbitMQ to extend AbstractStatusUpdaterBolt as the super class does a lot of useful things under the bonnet, which means that you would not use the Producer out of the box but will need to write some custom code.
Unless you are certain that there will be no duplicates URLs, you'll need to deduplicate the URLs before sending them to the queues anyway, which could be done e.g. with Redis within your custom status updater.
I have a something as following:
from("rabbitmq://...")
.process(processor1)
:
.process(processorn)
.process(SendToExternalAppProcessor)
The SendToExternalAppProcessor.process() uses producer template to send the some request formed from the contents in the exchange parameter to another rabbitmq2 with sendBody() method.
The issue is that once SendToExternalAppProcessor.process() executes and above route executes, it restarts above route again along with the listener of the rabbitmq2.
What I am missing here? Is there any apache camel configuration that is slipping from my attention?
PS: I know I have not given any concrete code here so as to replicate the scenario on your machine, but am in hope that experienced head and eyes will be quick to recall and suggest something. (Also I cannot straightway share my project code and also its big and complex)
Update:
I tried by commenting sendBody() and still restarts the route. I must be missing something weird basic setting here...
I think this is just a misunderstanding of the way routes work. 'from' is not a one-shot event; it will keep accepting messages from the source until you explicitly tell the route to stop.
"from " works as a normal rabbitmq consumer. The route is designed as always running.
If you just want to transfer exchanges to another rabbitmq , "to" is enough.
from("rabbitmq://...")
.process(processor1)
:
.process(processorn)
.to("rabbitmq://rabbit2...")
Please let us know which version of Camel you are using.
Are you using transacted camel flow? If any transaction mode is on then one possible issue could be JMS commit acknowledgment. May be Camel is consuming message and processing but not acknowledging rabbitmq. So message is still there and consuming again and again by camel route. By default it is AUTO_ACKNOWLEDGE, so that should not be the case if not transacted camel route.
My goal is to visualize the incoming data stream on a browser. I have used activemq to queue the stream. A single message consumed from the queue looks like this: "int,date/time,int,string". I have to update my line graph on the browser (every 100ms). Any ideas?
It sounds like a use case for WebSocket.
There are many ways to implement it, but a rather nice blog post on the topic is presented here.
Another way is to use MQTT directly from the browser using javascript and subscribe to a topic with your updates. You have to forward your data to that topic, in this case. For that, you can use composite queues with forwardOnly=false.
If you're using ActiveMQ, you could enable its websockets interface: http://activemq.apache.org/websockets.html
In your browser code, use the STOMP over WebSocket library to subscribe to the queue. http://jmesnil.net/stomp-websocket/doc/