Workflow Model Design

Workflow Model Design (AEM 6.5 LTS)

Design workflow models for AEM 6.5 LTS: step structure, transitions, OR/AND splits, variables, and model XML deployment via Package Manager.

Audience

Developers and workflow designers building or modifying AEM 6.5 LTS workflow models — via the Workflow Model Editor or by hand-authoring model XML and shipping it as a content package.

Variant Scope

• This skill is AEM 6.5 LTS only.
• Models can be stored at /conf/global/settings/workflow/models/ (preferred) or /etc/workflow/models/ (legacy — auto-deployed without Sync).
• Not for AEM as a Cloud Service. If the target instance is AEMaaCS, stop and use the cloud-service variant of this skill — /etc/workflow/models/ is deprecated, the Sync flow differs, and several patterns documented here will produce models that fail to deploy.

Dependencies

Models reference deployed WorkflowProcess and ParticipantStepChooser services by process.label / chooser.label or fully-qualified class name. Build and deploy the Java step first; reference it from the model second. A model that references a label whose service is not yet registered fails at runtime with Process not found — Sync will succeed and the model will appear in the editor, but instances will fail on first execution. See workflow-development for step implementation.

Prerequisites

• AEM 6.5 LTS author instance reachable (local, dev, or sandbox).
• Maven project with ui.content module — or the ability to author in the Workflow Model Editor and export as a content package.
• Required WorkflowProcess / ParticipantStepChooser services already implemented and deployed (see Dependencies above).
• filter.xml covering the model path you intend to install, with mode="merge".

Required Permissions

• workflow-editors (or equivalent write access to /conf/global/settings/workflow/models/) — create or modify models in the Workflow Model Editor or via content package.
• workflow-administrators (or equivalent) — start test workflow instances and terminate stuck test instances during iteration.
• Read access to /conf/global/settings/workflow/models/ and /var/workflow/models/ for verification.

Workflow

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Model Design Progress
- [ ] 1) Clarify the workflow purpose: what triggers it, what steps are needed, who approves
- [ ] 2) Map out steps: PROCESS (auto), PARTICIPANT (human), OR_SPLIT (decision), AND_SPLIT (parallel)
- [ ] 3) Decide payload type: single JCR_PATH or multi-page workflow package (a `cq:Page` collection, detected at runtime via `adaptTo(ResourceCollection.class)`)
- [ ] 4) Identify workflow variables needed for inter-step data passing
- [ ] 5) Design model XML: flow/parsys layer with correct nt:unstructured step components and sling:resourceType per step
- [ ] 6) Choose storage: `/conf/global/settings/workflow/models/<id>` (default; requires Sync) unless the user explicitly names a site — then `/conf/<site>/settings/workflow/models/<id>`; or `/etc/workflow/models/<id>` (legacy, auto-deployed)
- [ ] 7) Add filter.xml entry with mode="merge"
- [ ] 8) Deploy via mvn install or Package Manager
- [ ] 9) Open the model in Tools → Workflow → Models → Edit → Sync; verify the model appears in /var/workflow/models/ and all steps render on the editor canvas
- [ ] 10) Start a test workflow instance; confirm it runs to completion

Output Contract

Generate only these files for a /conf-based model:

Never generate — hard stops:

• ❌ Any file under jcr_root/var/ — AEM Sync writes /var/workflow/models/ automatically after you click Sync in the editor. Never ship /var content in a content package.
• ❌ A model/ directory inside jcr:content/ at the /conf path — a cq:WorkflowModel node with <nodes> and <transitions> is the runtime format. It must never appear under /conf. The Workflow Model Editor cannot open a model that contains it.
• ❌ <filter root="/var/workflow/models/..."/> in filter.xml — /var is never a package filter target. The only filter entry needed is the design-time /conf (or /etc) path.

filter.xml — correct entry:

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<filter root="/conf/global/settings/workflow/models/my-workflow" mode="merge"/>

Node Types Quick Reference

Default Path Rule

Unless the user explicitly names a specific AEM site, always generate models at /conf/global/settings/workflow/models/<id>. Do not infer a site-scoped path (e.g., /conf/wknd/…) from conversational context such as "for the WKND site" or "install on the WKND instance." Workflow models are not site-scoped by default — they are global resources. Only use /conf/<site>/settings/workflow/models/<id> when the user explicitly states that the model should be scoped to a specific site.

6.5 LTS: /conf vs /etc

Design-time vs runtime paths: /conf/global/settings/workflow/models/ stores the editor's flow/parsys format — this is what you author and deploy in a content package. Steps are nt:unstructured nodes with sling:resourceType; no cq:WorkflowNode or cq:WorkflowTransition nodes appear here. /var/workflow/models/ holds the runtime copy generated by Sync — it uses cq:WorkflowModel, cq:WorkflowNode, and cq:WorkflowTransition. Never write cq:WorkflowModel nodes to the /conf path, and never hand-author /var content — AEM manages the runtime layer entirely via Sync.

Deployment

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# Deploy via Maven
mvn clean install -P autoInstallPackage

# Or install package manually via Package Manager
http://localhost:4502/crx/packmgr

Architecture Considerations

These choices are made at design time and are hard to retrofit. Apply them before locking the model shape:

• Transient vs persistent. Set transient="true" on the model for high-volume, short-lived workflows (e.g., asset metadata extraction, replication side-effects). Transient instances create no JCR node under /var/workflow/instances until a retry or external-process step forces persistence — the difference between a healthy repository and unbounded growth.
• Participant timeouts. A PARTICIPANT step with no timeout can stall a workflow indefinitely and consume a job slot for the duration. For any human task that may not be acted on promptly, configure TIMEOUT and a TIMEOUT_HANDLER route on the step's metaData.
• Goto retry caps. Always enforce a hard cap on retry counters used by Goto Step rules (e.g., count < 3). An uncapped Goto loop will pin a worker thread and accumulate failed instances until the workflow is terminated by hand.
• Purge is a design-time concern. Estimate instance volume before go-live. Configure the Adobe Granite Workflow Purge Configuration factory in the same content package as the model so purge ships with the workflow, not as an after-the-fact follow-up. Set scheduledpurge.purgePackagePayload=true if the workflow uses workflow packages.
• Model versioning. In-flight instances stay bound to the model version they started with; new instances pick up the new version. When changing a deployed model, plan a brief drain window for old-version instances before declaring the change complete.

References

• step-types-catalog.md — complete step type reference with XML snippets
• model-xml-reference.md — full model XML structure and property reference
• model-design-patterns.md — common design patterns: linear, decision, parallel, loop-back
• architecture-overview.md — canonical foundation copy
• jcr-paths-reference.md — canonical foundation copy
• 65-lts-guardrails.md — canonical foundation copy