Achieving MQ functionality on z/OS using ActiveMQ - activemq

I am trying to validate if the WebsphereMQ feature (MQ Triggering) for remote execution of commands on z/OS can be achieved using ActiveMQ. Broadly, I think this will require custom java coding to leverage new frameworks/libs like JCICS (I think this needs CICS Tx Gateway v4.2).Broadly, need to validate the below steps :
a) Install ActiveMQ on z/OS
b) Write Java code to invoke the CKTI Task Initiator or Trigger Monitor in CICS to execute a command on z/OS using JCICS.
I Need to validate the above and correct or add new steps.

Why would you write Java code to invoke CKTI in order to start a CICS transaction? If your Java code is running, can't you use the issue() method of StartRequest to start a CICS transaction?
I think your design will turn out to be...
message arrives on ActiveMQ
send HTTP message to CICS
URIMAP definition causes your JCICS code to be invoked
JCICS code does a StartRequest.issue() to begin business logic
Send a response to original HTTP message indicating success or failure of issue()

Related

Spring boot websocket test

I have a spring boot project with websocket and I want to test the project sending multiple request to the socket from different users. I want to use threads to imitate the users that send data from the web app but I don't know exactly how to make the test. Can anyone help me, and show one simple test for an websocket using threads?
You can use JMeter for testing your websocket project.
For further reading:
https://www.blazemeter.com/blog/websocket-testing-apache-jmeter
http://www.baeldung.com/websockets-spring
Good example:
https://github.com/Fyro-Ing/JMeter-WebSocket-StompSampler
When writing a Spring Boot application using STOMP on websockets, I struggled a lot to find out how to configure a test client.
I ended up writing a little library called Jackstomp to make it easier to create type-safe tests for STOMP WS applications using JSON as message body.
I haven't used it with multiple threads, but you should be able to easily use it within each thread to create independent clients for each user and perform basic operations. (Please note that a different client should be used in each thread).
The point is that you can really express a synchronous flow for each client, including actively querying for received events.
Even if you don't use this library, you can look at the code to get a grasp of the different things to setup.

How to use NServiceBus with MSMQ

I am experimenting the new version of NServicsBus. I find following step by step sample on particular site.
https://docs.particular.net/samples/step-by-step/
Can any one tell me how to configure MSMQ for Transport. Here is my scenario.
Client create message
Client message should be stored in MSMQ
Server Application running on same machine which subscribe the message.
Server handler get message from MSMQ and process it further. i.e Store in DB or send to other web service.
Retry to process message if it does not worked first time
after 3 retries send message to error queue
How do i configure this sample to use MSMQ for my scenario.
Helpful information to include
Product name:NServiceBus.Core
Version: 6.3.4
Stacktrace:
Description:
Did you know that we have released a LearningTransport and LearningPersistence just for purposes like these? Have a look at it here.
Having said that, the transport swapping should be rather seamless so even if you have setup a small PoC using this transport/persistence, you can change it to MSMQ or other production-ready transports/persistence when you go live.
Again, as stated in the documentation page and as the name suggests, this is not for use in production.
I would recommend you walk through this.
https://docs.particular.net/tutorials/intro-to-nservicebus/
Will answer your questions, and future ones you have.

Get Number of connection from all host to my activemq broker

ActiveMQ broker setup:
Broker is running on machine: hostA
Clients from different host can connect to my broker instance running on hostA, there can be any number of client from any host.
Is there a way to find out how many clients are connected to broker and also list which tell me how many connection from each host is there to my broker.
I want to do this without making assumption about number of hosts.
I can do this by using lsof command and some parsing over output, but I am in situation where I can not use this.
Is there any feature provided by ActiveMQ command line utility activemq-admin.
You can get to pretty much any Mbean attribute ActiveMQ exposes via the activemq-admin. There are no attributes or operations that give you a quick count of connections from specific clients. You will have to do some work on your end to get all the details you want, but all the raw data is there.
Examples:
Broker Stats:
activemq-admin query --objname type=Broker,brokerName=localhost
Connection Stats
activemq-admin query --objname type=Broker,brokerName=localhost,connector=clientConnectors,connectorName=<transport connector name>,connectionViewType=clientId,connectionName=*
See full doc here.
NOTE: Documentation as of this writting has not be updated to take into account the Mbean changes made in AMQ. References to Object names in examples are not correct.
You can get the object name (or example sytax) from JMX (using jconsole or visual vm for example) from the MBeanInfo. Each object name wills stat something like org.apache.activemq:type. For the script, remove the "org.apache.activemq:" and you should be in business for any thing you need from JMX via the script.
I think you may also look into using Jolokia with your broker. Although not compatible with the activemq-admin script, you can reach everything you can from the activemq-admin script, but also have access to all of the operations. In the past I've heavily used the activemq-admin script for local monitoring/command line administration of the broker, but have started converting everything to hit the Jolokia service. But again, activemq-admin will give you a way to access what you are looking for here.

Can any queuing system trigger external Applications

Right now we have a queuing system(activemq) which is storing the messages. And we have written a separate java application that will read the queue and then trigger a exe to do some processing. But we want to do away with this extra application that is linking our activemq and exe. So i want to know whether any queuing system houses a code which will help me run the exe without any extra code written by me.
Any inputs regarding which queuing system can get me this done will be greatly appreciated.
This isn't really how Message Brokers work. You could however embed a broker inside your own application or create a broker plugin to do something. In the end though the best way to do this is to create your own client that can implement your business logic and let the Message Broker do what it was designed to do, route message traffic.
If you want more of a 'push' solution rather than a producer-consumer solution (which sounds to me like you are) you could look into the use of WebSockets. That would be another way of dealing with messages.
As others have said it doesn't look like using a message broker is the solution you want if you don't want to have some additional middleware to provide asynchronous communication.
So you just need something to launch an EXE on message arrival?
Message Queuing Triggers
Just some additional information for you... Triggered applications are natively supported in IBM Websphere MQ via a Trigger Monitor application that runs as a service (in windows implementations) or a daemon (in UNixish implementations).
When a message arrives in a queue, the MQ software will generate another message ("Trigger" message and send it to the "Trigger" queue, which is being monitored by the Trigger Manager app. The app then starts the required application.
So your implementation of an "app to start an app" is not odd ball or strange at all.. IBM do it in their implementation. I see nothing wrong with your implementation and if you can integrate it tighter to activeMQ then you are on a winner.
What about IBM MQ's triggering feature ?
WebSphere MQ provides a feature that enables an application or channel to be started automatically when there are messages available to retrieve from a queue. A message is put to a queue defined as triggered. If a series of conditions are met, the queue manager sends a trigger message to an initiation queue.
https://www.ibm.com/support/knowledgecenter/en/SSFKSJ_9.0.0/com.ibm.mq.dev.doc/q026940_.htm

Deploying java client, RabbitMQ, and Celery to server

I have a Java API on my server, and I want it to create tasks and add them to Celery via RabbitMQ. I followed the following tutorial, http://www.rabbitmq.com/tutorials/tutorial-two-python.html, where I used java for the client (send.java) and python to receive (receive.py). In receive.py, where the callback method is invoked, I call a method that I've annotated with #celery.task so that the task is added to celery.
I'm wondering how all of this is deployed on a server though, specifically, why there is a receive.py file. Is receive.py a process that must continually run on the server? Is there a way to configure RabbitMQ so that it automatically routes java client tasks to celery?
Thanks!
RabbitMQ is just a message queue. Producers put messages and consumers get them on demand. You can only restrict access for specific queues via RabbitMQ's auth options.
As for deployment: yes, receive.py needs to continuously run. It is Celery's job to do that. See the Workers Guide for info on running a worker.