Workflow Launchers

Workflow Launchers Skill — AEM as a Cloud Service

Purpose

This skill teaches you how to configure and deploy Workflow Launchers that automatically start workflows in response to JCR content changes on AEM as a Cloud Service.

When to Use This Skill

• A workflow must start automatically when an asset is uploaded to DAM
• A review workflow should trigger whenever an author modifies content under a specific path
• You need to replicate or replace an OOTB launcher behavior without editing /libs
• You want to enable, disable, or restrict a launcher to specific run modes

Core Concept: What Is a Workflow Launcher?

A Workflow Launcher (cq:WorkflowLauncher) is a JCR node that registers a JCR event listener. When a node event occurs at a path matching the launcher's glob pattern, node type, and conditions, the Granite Workflow Engine enqueues a workflow start.

The listener is managed by WorkflowLauncherListener (an OSGi service). It reads all active launcher configurations at startup and re-evaluates them when configurations change.

Architecture at a Glance

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JCR Event (NODE_ADDED / NODE_MODIFIED / NODE_REMOVED)
    ↓
WorkflowLauncherListener (OSGi EventListener)
    ↓ matches: glob, nodetype, event type, conditions
Workflow Engine: enqueue WorkflowData
    ↓
Workflow Instance created at /var/workflow/instances/

Launcher Configuration Properties

Deploying a Custom Launcher on Cloud Service

On Cloud Service, /libs is immutable. Store launcher configurations at:

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/conf/global/settings/workflow/launcher/config/<launcher-name>

Maven project location:

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ui.content/src/main/content/jcr_root/conf/global/settings/workflow/launcher/config/
    my-custom-launcher/
        .content.xml

Filter in filter.xml:

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<filter root="/conf/global/settings/workflow/launcher/config/my-custom-launcher"/>

Node structure (.content.xml):

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<?xml version="1.0" encoding="UTF-8"?>
<jcr:root
    xmlns:jcr="http://www.jcp.org/jcr/1.0"
    xmlns:cq="http://www.day.com/jcr/cq/1.0"
    jcr:primaryType="cq:WorkflowLauncher"
    eventType="{Long}1"
    glob="/content/dam(/.*)?/jcr:content/renditions/original"
    nodetype="nt:file"
    workflow="/var/workflow/models/dam/update_asset"
    enabled="{Boolean}true"
    description="Start DAM update workflow on new original rendition upload"
    runModes="[author]"/>

Overlaying an OOTB Launcher

To disable or modify an OOTB launcher (e.g., dam_update_asset_create):

1. Copy the node from /libs/settings/workflow/launcher/config/dam_update_asset_create to /conf/global/settings/workflow/launcher/config/dam_update_asset_create
2. Modify the property (e.g., set enabled="{Boolean}false" to disable it)
3. Deploy as a content package via Cloud Manager

Common OOTB Launchers (Cloud Service)

Event Type Combinations

To listen for both ADD and MODIFY, combine event types:

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eventType="{Long}3"  <!-- 1 (ADD) + 2 (MODIFY) = 3 -->

Where-Clause Conditions

The conditions array lets you add JCR property conditions on the triggering node:

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conditions="[property=cq:type,value=publicationevent,type=STRING]"

Condition format: property=<name>,value=<value>,type=<JCR_TYPE> (type is optional, defaults to STRING).

Disabling a Launcher for a Run Mode

Use runModes to restrict:

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runModes="[author]"   <!-- only fires on Author -->
runModes="[publish]"  <!-- only fires on Publish -->

Omit runModes to fire on all run modes.

Debugging Launchers

• Tools → Workflow → Launchers UI — lists all active launchers, you can enable/disable interactively
• Check /conf/global/settings/workflow/launcher/config/ in CRXDE Lite for your deployed configs
• Check OSGi console → WorkflowLauncherListener service properties
• After deployment, verify via: curl -u admin:admin http://localhost:4502/etc/workflow/launcher.json

References in This Skill