Events

Event steps allow flows to publish business events that can trigger other processes through the publish-subscribe pattern.

Publish Event

Raises a business event that can trigger event handlers.

Parameter	Description
Event Definition	The event type to publish
Event Properties Binding	Mapping of values to event properties

When an event is published:

1. An immutable event instance is created
2. All synchronous handlers execute immediately (in order)
3. Asynchronous handlers are queued for background execution
4. The flow continues after synchronous handlers complete

Example - Simple Event:

PUBLISH EVENT
  Event Definition: OrderPlaced
  Event Properties Binding:
    OrderId: Order.Id
    CustomerId: Order.CustomerId
    OrderNumber: Order.OrderNumber
    TotalAmount: Order.TotalAmount
    OrderDate: NOW()

Example - Event with Calculated Properties:

# First calculate some values
RUN LOGIC BLOCK
  Logic Block: CalculateOrderMetrics
  Inputs: Order
  → Outputs: IsHighValue, IsFirstOrder, CustomerLifetimeValue

# Then publish event with all data
PUBLISH EVENT
  Event Definition: OrderCompleted
  Event Properties Binding:
    OrderId: Order.Id
    CustomerId: Order.CustomerId
    TotalAmount: Order.TotalAmount
    IsHighValue: IsHighValue
    IsFirstOrder: IsFirstOrder
    CustomerLifetimeValue: CustomerLifetimeValue
    CompletedDate: NOW()
    ProcessedBy: CurrentUser.Id

Event Patterns

Workflow Completion Events

Publish events when significant workflow milestones are reached:

# At the end of an order processing flow

CONDITION: Order Fully Processed?
  Condition: AllStepsSuccessful == true
  
  TRUE BRANCH:
    PUBLISH EVENT
      Event Definition: OrderProcessingCompleted
      Event Properties Binding:
        OrderId: Order.Id
        ProcessingDuration: DATEDIFF(StartTime, NOW())
        ItemsProcessed: ProcessedCount
        Status: "Success"
  
  FALSE BRANCH:
    PUBLISH EVENT
      Event Definition: OrderProcessingFailed
      Event Properties Binding:
        OrderId: Order.Id
        FailureReason: ErrorMessage
        FailedAtStep: FailedStepName
        Status: "Failed"

Entity Lifecycle Events

Publish events at key points in an entity's lifecycle:

# Customer Onboarding Flow

# After initial setup
PUBLISH EVENT
  Event Definition: CustomerCreated
  Event Properties Binding:
    CustomerId: Customer.Id
    CustomerName: Customer.Name
    CreatedBy: CurrentUser.Id

# ... additional onboarding steps ...

# After onboarding complete
PUBLISH EVENT
  Event Definition: CustomerOnboarded
  Event Properties Binding:
    CustomerId: Customer.Id
    OnboardingDuration: DATEDIFF(Customer.CreatedOn, NOW())
    AssignedAccountManager: Customer.AccountManagerId

Integration Events

Publish events when external system interactions complete:

# After payment processing
CALL REST API
  Service Connection: PaymentGateway
  Operation: ProcessPayment
  → PaymentResult

PUBLISH EVENT
  Event Definition: PaymentProcessed
  Event Properties Binding:
    OrderId: Order.Id
    PaymentAmount: Order.TotalAmount
    TransactionId: PaymentResult.TransactionId
    PaymentMethod: SelectedMethod
    Success: PaymentResult.Status == "approved"
    ProcessedAt: NOW()

Batch Processing Events

Publish events during and after batch operations:

# Batch processing flow
NEW VARIABLE: ProcessedCount = 0
NEW VARIABLE: ErrorCount = 0

ITERATOR: Process Records
  Collection: RecordsToProcess
  Item Variable: Record
  
  Steps:
    # Process each record...
    
    # Publish progress event periodically
    CONDITION: Should Report Progress?
      Condition: ProcessedCount % 100 == 0
      
      TRUE BRANCH:
        PUBLISH EVENT
          Event Definition: BatchProgressUpdate
          Event Properties Binding:
            BatchId: BatchJob.Id
            ProcessedCount: ProcessedCount
            TotalCount: TotalRecords
            PercentComplete: (ProcessedCount / TotalRecords) * 100

# After batch completes
PUBLISH EVENT
  Event Definition: BatchCompleted
  Event Properties Binding:
    BatchId: BatchJob.Id
    TotalProcessed: ProcessedCount
    ErrorCount: ErrorCount
    Duration: DATEDIFF(BatchStartTime, NOW())

Best Practices

Publish at Business Moments: Events should represent meaningful business occurrences, not technical operations. "OrderPlaced" is better than "RecordSaved".

Include Sufficient Context: Event properties should contain enough information for handlers to do their work without additional queries.

Keep Events Focused: Each event should represent one thing that happened. Don't combine multiple events into one.

Consider Handler Execution: Remember that synchronous handlers block the publishing flow. Keep synchronous handlers fast and move heavy processing to asynchronous handlers.

Don't Rely on Handler Success: The publishing flow should not depend on what handlers do. Handlers may fail independently.

Avoid Circular Events: Be careful not to create event chains where handlers publish events that trigger the original flow.

Document Event Contracts: Clearly document when each event is published and what properties it provides so handler developers know what to expect.

Event Handlers

Events by themselves don't do anything—they need Event Handlers to respond to them. See Event documentation for details on creating Event Definitions and Event Handlers.