Using ActiveMQ with Alfresco 7.4

[angelborroy]

ActiveMQ is used in the Alfresco stack to handle event-driven communications between a number of Alfresco services: Repository, Transform, Search Enterprise and Sync. The interaction happens by using asynchronous messaging queues and topics, where the services produce and consume events. This asynchronous processing increases the capacity to scale up Alfresco and also improves the management of time-consuming operations. Messages delivery is guaranteed by using JMS protocol.

Additionally any external asynchronous service can be configured as consumer of Repository messages using the Alfresco Out of Process SDK.

This blog post describes different configurations for using ActiveMQ with Alfresco 7.4.

If you are interested in the installation of ActiveMQ, refer following material:

• Alfresco - ActiveMQ basic setup
• Dockerfile for ActiveMQ with TLS

Sample code and Docker Compose templates are available in https://github.com/aborroy/alfresco-activemq-74

Alfresco Community

Repository produces messages for document creation and update operations using a topic named alfresco.repo.event2

An important limitation is that Alfresco Community doesn't include permissions data in this asynchronous messages (while Alfresco Enterprise does).

This is the reason why the most common scenario for Alfresco Community 7.4 deployments is to disable asynchronous messages production and not to desploy ActiveMQ service.

Add following properties to Alfresco Repository service to disable async messages production:

messaging.subsystem.autoStart=false
repo.event2.enabled=false

Docker Compose sample for Alfresco Community is available in https://github.com/aborroy/alfresco-activemq-74/tree/main/docker-community

Alfresco Enterprise

In addition to the Repository service producing messages (in this case with permission data on them), Alfresco Enterprise deployments include a number of services that relies on asynchronous communication:

• Transform Service for managing transformation and rendition operations
• Search Enterprise for managing indexing operations (metadata, content and path)
• Sync Service for managing messages with Desktop Sync

If any of this services is required, setting up and deploying ActiveMQ is a must.

AIO

When using AIO (All-In-One) service deployments for Transform and Search, following queues and topics are used in ActiveMQ by default.

Service	Type	Name
Repository	TOPIC	alfresco.repo.event2
	QUEUE	acs-repo-transform-request
	QUEUE	acs-repo-rendition-events
Transform	QUEUE	org.alfresco.transform.ad9cab37-5f02.t-reply
	QUEUE	org.alfresco.transform.engine.aio.acs
	QUEUE	org.alfresco.transform.engine.notUsedByRouter.acs
	QUEUE	org.alfresco.transform.engine.t-reply.acs
	QUEUE	org.alfresco.transform.t-request.acs
Search	QUEUE	org.alfresco.search.content.event
	QUEUE	org.alfresco.search.contentrefresh.event
	QUEUE	org.alfresco.search.contentstore.event
	QUEUE	org.alfresco.search.metadata.event
	QUEUE	org.alfresco.search.metadata.retry.event
	QUEUE	org.alfresco.search.path.event
Sync	TOPIC	VirtualTopic.alfresco.repo.events.nodes

Sample Docker Compose deployment for this configuration is available in https://github.com/aborroy/alfresco-activemq-74/tree/main/docker-aio

Individual

When using Individual service deployments for Transform and Search, following queues and topics are used in ActiveMQ by default.

Service	Type	Name
Repository	TOPIC	alfresco.repo.event2
	QUEUE	acs-repo-transform-request
	QUEUE	acs-repo-rendition-events
Transform	QUEUE	org.alfresco.transform.ad9cab37-5f02.t-reply
	QUEUE	org.alfresco.transform.engine.imagemagick.acs
	QUEUE	org.alfresco.transform.engine.libreoffice.acs
	QUEUE	org.alfresco.transform.engine.tika.acs
	QUEUE	org.alfresco.transform.engine.alfresco-pdf-renderer.acs
	QUEUE	org.alfresco.transform.engine.misc.acs
	QUEUE	org.alfresco.transform.engine.notUsedByRouter.acs
	QUEUE	org.alfresco.transform.engine.t-reply.acs
	QUEUE	org.alfresco.transform.t-request.acs
Search	QUEUE	org.alfresco.search.content.event
	QUEUE	org.alfresco.search.contentrefresh.event
	QUEUE	org.alfresco.search.contentstore.event
	QUEUE	org.alfresco.search.metadata.event
	QUEUE	org.alfresco.search.metadata.retry.event
	QUEUE	org.alfresco.search.path.event
Sync	TOPIC	VirtualTopic.alfresco.repo.events.nodes

Sample Docker Compose deployment for this configuration is available in https://github.com/aborroy/alfresco-activemq-74/tree/main/docker-split

ActiveMQ Web Console

Once a Docker Compose deployment is up & ready, ActiveMQ Web Console is available by default in http://localhost:8161 with default credentials admin/admin

Using Docker Volumes

Docker Compose templates provided in this article are not using local storage with Docker Volumes. Enabling this feature can be done using a configuration like the following one.

activemq:
    image: alfresco/alfresco-activemq:5.17.1-jre11-rockylinux8
    mem_limit: 1g
    ports:
        - 8161:8161
    volumes:
        - ./data/activemq-data:/opt/activemq/data

ActiveMQ data folder includes both data and log information.

Service Dependencies

Following table shows dependent services that require to be deployed when using a given service.

• Transform Service only requires the use of ActiveMQ
• Search Enterprise requires ActiveMQ, events2 in Repository and Transform Service
• Sync Service requires ActiveMQ and events in Repository
• Out-Of-Process SDK requires ActiveMQ and events2 in Repository

[1] events2: https://github.com/Alfresco/alfresco-community-repo/blob/23.1.0.181/repository/src/main/resources/al...

[2] events: https://github.com/Alfresco/alfresco-community-repo/blob/23.1.0.181/repository/src/main/resources/al...

Monitoring

ActiveMQ can be monitored using different tools. Reference project includes a sample for some of then in https://github.com/aborroy/alfresco-activemq-74/tree/main/docker-aio-monitoring

• JMX using jconsole
• Jolokia Metrics
• Prometheus
• Grafana

You can find additional usage details in the GitHub project. Remember that this material should be only used as reference, you may need to adapt or to enrich this base depending on your requirements.

Maintenance

Following points require periodic maintenance:

• Create a backup of data and conf folders
• Analyze log files in data folder
• Monitor service resources usage (like CPU and RAM consumption)
• Monitor disk space usage for ActiveMQ data folder
• Clear message queues when neccesary, removing pending or unused messages

Advisory Messages may be disabled, but this feature is adding small overhead in terms of memory and connection resources. Even with that, in some cases it can make sense to disable all advisories.

Video Recording

Additional details are available in the following video.