BPMN Process Engine

BpmnProcessEngine offers a lightweight BPMN execution/simulation layer that runs inside Flow, tracking token activity, honoring start/service/task/gateway semantics, and exposing pause/resume/terminate controllers. It is designed for demos, debugging, or hooking into AI/automation systems.

Capabilities

• Token-based execution with event callbacks so you can drive timelines, logs, or dashboards
• Customizable task executor and variable evaluator to plug in backend calls or business logic
• Lifecycle helpers (pause, resume, terminate) for building interactive simulations or training flows

Main APIs

API	Description
loadProcess(nodes, edges)	Loads Flow nodes/edges (typically from bpmnXmlToFlow) into the engine
createInstance(initialVariables?)	Creates a process instance with tokens, variables, and meta
start(instanceId)	Starts the instance and moves tokens along the graph
pause(instanceId) / resume(instanceId)	Pause / resume execution for demos
terminate(instanceId)	Forcefully stops an instance
setVariable(instanceId, key, value)	Update runtime variables for conditional gateways
getVariable(instanceId, key)	Read the current value of a variable
getInstance(instanceId) / getAllInstances()	Inspect instance state, node map, history

Example

The demo below loads a sample BPMN, starts an instance, pauses/resumes/terminates it, and shows event logs from the engine.

Status: idle

• Process loaded

BPMN Process Execution

Best Practices

1. Hook eventListener into a dashboard so you can visualize node enter/exit and token events.
2. Use taskExecutor to connect to backends, AI services, or async approval workflows.
3. Update variables via setVariable during execution to influence gateway routing.