VM component in Mule 4
We use VM because:
1) The
Virtual Machine (VM) connector handles intra-app and inter-app communication
through asynchronous queues that can be transient or persistent.
2) Transient
queues are faster than persistent queues, but they are not reliable in the case
of a system crash.
3) Persistent
queues are slower but reliable.
4) When
running on a single instance, persistent queues work by serializing and storing
the contents on the disk.
When to
Use the VM Connector:
1) When you
want to pass messages from one flow to another through a queuing mechanism,
instead of using <flow-ref /> directly.
2) When you
want to distribute work across a cluster.
3) When you
want to communicate with different apps that are running in the same Mule
domain.
4) When you
need simple queuing that does not justify a full JMS broker.
Components in VM:
1. Publish: Publish the content
to the queue
2. Listen: It listens to the VM
queues
3. Consume: Pull one message from
a queue. If the message is not immediately available, a message will wait up to configured
queue timeout.
4. Publish Consume: Publishes the
given content into a queue and then awaits up to the queue timeout for a
response to be supply on a temporal reply- to queue that this operation
automatically creates.
The flow of Publish:
Publish component configuration:
Connector configuration:
Flow of listener:
Method: GET
Input:
Output:
So, you can see clearly that the process is asynchronous and separate threads are executing for both the flows.
The first thread is executing loggers
before VM and after VM and the second thread is executing payload logger that is
Hello.
The flow of publish consume:
The flow of listener:
Method: GET
Output:
XML project code:
<?xml version="1.0" encoding="UTF-8"?>
<mule xmlns:sockets="http://www.mulesoft.org/schema/mule/sockets" xmlns:http="http://www.mulesoft.org/schema/mule/http"
xmlns:vm="http://www.mulesoft.org/schema/mule/vm"
xmlns="http://www.mulesoft.org/schema/mule/core" xmlns:doc="http://www.mulesoft.org/schema/mule/documentation" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
http://www.mulesoft.org/schema/mule/vm http://www.mulesoft.org/schema/mule/vm/current/mule-vm.xsd
http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
http://www.mulesoft.org/schema/mule/sockets http://www.mulesoft.org/schema/mule/sockets/current/mule-sockets.xsd">
<vm:config name="VM_Config" doc:name="VM Config" doc:id="162fd81e-d7e3-4443-b95c-068f452be47b">
<vm:queues >
<vm:queue queueName="vm" />
</vm:queues>
</vm:config>
<http:listener-config name="HTTP_Listener_config" doc:name="HTTP Listener config" doc:id="f34f130a-ff45-41df-a8b0-e5a1192329a4" >
<http:listener-connection host="0.0.0.0" port="8085" />
</http:listener-config>
<flow name="test_vmFlow" doc:id="7cd43a2d-0bec-400a-93e7-92f1fd6bf145" >
<http:listener doc:name="Listener" doc:id="f941a0ea-db90-471d-97b4-b94002d4c608" config-ref="HTTP_Listener_config" path="/vm"/>
<logger level="INFO" doc:name="Logger" doc:id="9675b9e8-d6b2-4720-9f68-3ab0094ea9e9" message="before vm"/>
<vm:publish queueName="vm" doc:name="Publish" doc:id="9df15d7a-792a-40a8-ad13-96ed7108475e" config-ref="VM_Config" sendCorrelationId="ALWAYS">
</vm:publish>
<logger level="INFO" doc:name="Logger" doc:id="cbcf0b10-3a48-43d5-ba7b-c5dec877a457" message="after vm"/>
</flow>
<flow name="test_vmFlow1" doc:id="69cd8eb2-0fd5-408c-bc25-251c40249198" >
<vm:listener queueName="vm" doc:name="Listener" doc:id="30fd3738-201b-4428-8e90-42140ec82688" config-ref="VM_Config"/>
<logger level="INFO" doc:name="Logger" doc:id="106b97e9-9be5-462c-8303-dffc60777e85" message="#[payload]"/>
</flow>
<flow name="test_vmFlow2" doc:id="46726825-5875-41b8-b498-47a3622c00fa" >
<http:listener doc:name="Listener" doc:id="34fdd984-c2db-4235-852a-e052a542ec8b" config-ref="HTTP_Listener_config" path="/vm1"/>
<logger level="INFO" doc:name="Logger" doc:id="3c4cd112-9d94-4e1f-9316-2f9aca97df8d" message="before vm"/>
<vm:publish-consume queueName="vm" doc:name="Publish consume" doc:id="23ca2046-49d1-4786-b6b4-e412296d031b" config-ref="VM_Config"/>
<logger level="INFO" doc:name="Logger" doc:id="76f7a5a4-b3e2-4639-a6f1-882c3c08a418" message="after vm"/>
</flow>
<flow name="test_vmFlow3" doc:id="46cf614a-3464-49ee-b378-323d93dbe09f" >
<vm:listener doc:name="Listener" doc:id="26f18453-7287-46ea-bd4e-a47bce7af9b5" config-ref="VM_Config" queueName="vm"/>
<logger level="INFO" doc:name="Logger" doc:id="149cf101-6bb7-4f1d-840e-150ba1e6a780" message="#[payload]"/>
</flow>
<!-- <flow name="test_vmFlow1" doc:id="d2781c31-b6e2-4394-883c-f7afc844ecd1" >
<vm:listener queueName="vm" doc:name="Listener" doc:id="62ab05f9-3adc-4ff4-a646-58603c2b719f" config-ref="VM_Config"/>
<logger level="INFO" doc:name="Logger" doc:id="9c30c72f-51a6-49f4-8d63-9d1be38cc32b" message="after vm #[payload]"/>
</flow> -->
</mule>
No comments:
Post a Comment