How to write a camel route
with timer..which will read from a jms queue
I have tried like this but not working
example
from(timer:mytimer)
.from("jms:queue)
Please let me know if there is any way
Related
I'm new to activeMQ / Camel, so please bear with me.
In a camel route, I use a splitter to spawn multiple sub routes. Each one of this routes will use some external APIs to do some job, and poll until job is done. I'm that far.
Now I need to trigger a last action to collect the result of all of these routes. How would I do that the Camel / AMQ way ?
I was thinking of posting a message in each sub-route to an AMQ queue, but I haven't found a way yet to wait for the N messages to be received in that queue before consuming it in my final Camel route.
Thank you.
If you need to collect all the results from the splitter sub-routes and execute some action on those results after all the sub-routes are completed then you can use an aggregation strategy(https://camel.apache.org/manual/latest/aggregate-eip.html) on the splitter.
By using an aggregation strategy, the Exchange after the split will contain the results of all the sub-routes.
Example using the Java DSL:
.split(expression, new GroupedExchangeAggregationStrategy())
...
.end()
The GroupedExchangeAggregationStrategy aggregates all split Exchanges into a list. You can use another predefined aggregation strategy if you need, or you can create a custom one by extending org.apache.camel.processor.aggregate.AggregationStrategy.
I have a camel route setup like the following to send a java object to an activemq queue.
from("direct:clientRequest")
.marshal().json(JsonLibrary.Jackson)
.to("activemq:queue:command");
I want to do the following:
Map the "clientRequest" uri to some Java method
Use ProducerTemplate's "sendBody" method to send a JSON form of a Java object to the activemq queue.
Is this possible?
I am asking this question after a lot of homework. Please suggest a way to do this.
You can use pojo producing in Apache Camel. See this page for more details
http://camel.apache.org/pojo-producing.html
And there is an example that shows more about using pojo producing/consuming in Camel
http://camel.apache.org/pojo-messaging-example.html
Is it possible to aggregate thread processing data from a Seda queue in camel?
Can anyone suggest how it can be done?
You can setup the camel route like this, and you can find more example here
from("seda:header").setHeader("visited", constant(true)).aggregate(header("cheese")).to("mock:result");
The need is to have a Camel (Mina/Netty) based TCP server running on a specific port, which allows multiple TCP clients to connect to it. The content to be streamed is available in files and the TCP server has to send each line in the text files to one of the connected clients (round robin).
Can someone help me with the outline of a camel route to achieve this?
Also it is possible to throttle the streaming speed for example 100 msg/sec per connected client?
Thanks in advance.
MK
I have done something like this. Well not quite exactly to what you want but I can make some suggestions on how to get started.
Lets use the MINA component for this route as I had some issues with the Netty component see this link Exception thrown from Apache Camel Netty Consumer When more than one client sends data. Apparently this has been fixed but as my project got cancelled I never tested it again.
So from your description this will be a text line based protocol a simple route for this would look like this in the DSL
<route>
<from uri="mina2:tcp://localhost:5555?textline=true"/>
<to uri="bean:fileProcessing"/>
</route>
This route will open a listening socket on the localhost on port 5555. The route is also setup to use a textline codec. A textline codec is essentially a line of text terminated end of line character i.e. \n. If you are going to be using some other protocol you will need to look into the following items:
ProtocolEncoder—The ProtocolEncoder handles the task of taking an input
payload and putting bytes onto the TCP channel.
ProtocolDecoder—The ProtocolDecoder interprets the custom
binary protocol message to something your application can understand.
ProtocolCodecFactory— This creates the encoder and decoder.
You could implement some logic in the fileProcessing bean to send the replies back. There is a catch however the clients will have to request when they are ready to get a new line. From my understanding this follows a request reply scenario. However from what I have seen the route is only active when there is a message coming in from the client to the server.
There might be a way to initiate the sending from the server but you will need to experiment with that by yourself on getting it done I have not done anything like that myself.
Critical reading would be the following.
Mina Documentation
Blog Entry On Using MINA
My suggestion is to start with a basic route like this and then expand your logic and then come back with problems you might encounter.
UPDATE:
So I did a little research on this and it does not appear possible to send events from the server to the client without following one of the following patterns InOnly and InOut.
Try just using MINA or Netty then.
What's the best strategy to send SMS via SMPP with Camel ? Should I use the ProducerTemplate ?
I'm new to camel so I'm not confident if my strategy is the best.
In my application upon reception of an SMS, I have to send back an other SMS with some computed content.
I created a
route smsIn that looks like this
from "uri=smpp ..."
unmarshal ref="bindyDataFormat"
to "uri=bean:myBean
and a route smsOut with
from "uri=direct:smsOut"
to "uri=smpp ..."
The smsIn route, receives the sms, transforms its conent (csv data) in a pojo and send that pojo to myBean.
In myBean I do some processing and then call a ProducerTemplate which send my computed message to the endpoint "direct:smsOut".
The reason I use the producerTemplate is that I have to set some info from my pojo in the header (CamelSmppDestAddr) and the body of the Exchange.
I have tested with the logica SMSC simulator, this seems to work fine, but would like to have your opinion about this solution ?
What about reliability , transaction ?
Should I store my message before trying to send it to the SMSC ?
Should I store it in a database, post it to a queue ?
I'm not sure why you have a producer template, you could just build up the route instead (given that you return something from your bean or takes an Exchange as paramter).
<from uri="smpp: ..."/>
<bean ref="bean:myBean"/>
<to uri="jms:queue:myQueue"/>
then not use direct, but use a JMS queue that is transactional and persistent. Say your smpp call fails, the message would have been gone. Using a queue like this and make sure its transactional, you can make sure not to lose data in this stage of the route.
<from uri="jms:queue:myQueue"/>
<transactional/>
<to uri="smpp.."/>
I suggest using Apache ActiveMQ as JMS middleware. Actually, if you download ActiveMQ, you get camel bundled, so you could actually run your Camel routes from ActiveMQ.
You might want to tweak how retries and error handling occurs dependent on what you want to happen (retry every second forever?, retry five times, then put to error queue? etc).
Read this page: Transaction Error handling in Camel
For deeper info and more tweaks, you might also want to read this:
Transactional Client