RegisterTrigger

Register a trigger to automatically invoke a function

Request

Register a trigger that will automatically invoke a function when certain conditions are met.

Response

The framework responds with a TriggerRegistrationResult message.

type · string

Message type. Will be "triggerregistrationresult".

id · string · required

The trigger ID from the request.

trigger_type · string · required

The trigger type from the request.

function_id · string · required

The function ID from the request.

error · object

Error details if registration failed. Omitted if successful.

Show properties

code · string · required

Machine-readable error code (e.g., "trigger_type_not_found", "invalid_config", "function_not_found").

message · string · required

Human-readable error message describing what went wrong.

Examples

HTTP Trigger Registration

Request:

{
  "type": "registertrigger",
  "id": "http_webhook_handler",
  "trigger_type": "http",
  "function_id": "process_webhook",
  "config": {
    "path": "/webhooks/github",
    "method": "POST"
  }
}

Success Response:

{
  "type": "triggerregistrationresult",
  "id": "http_webhook_handler",
  "trigger_type": "http",
  "function_id": "process_webhook"
}

Cron Trigger Registration

Request:

{
  "type": "registertrigger",
  "id": "daily_report",
  "trigger_type": "cron",
  "function_id": "generate_report",
  "config": {
    "schedule": "0 9 * * *",
    "timezone": "America/New_York"
  }
}

Success Response:

{
  "type": "triggerregistrationresult",
  "id": "daily_report",
  "trigger_type": "cron",
  "function_id": "generate_report"
}

Queue Trigger Registration

Request:

{
  "type": "registertrigger",
  "id": "email_queue_processor",
  "trigger_type": "queue",
  "function_id": "send_email",
  "config": {
    "queue_name": "email_queue",
    "batch_size": 10,
    "visibility_timeout": 30
  }
}

Success Response:

{
  "type": "triggerregistrationresult",
  "id": "email_queue_processor",
  "trigger_type": "queue",
  "function_id": "send_email"
}

Error Cases

Trigger Type Not Found

Request:

{
  "type": "registertrigger",
  "id": "my_trigger",
  "trigger_type": "nonexistent_type",
  "function_id": "my_function",
  "config": {}
}

Error Response:

{
  "type": "triggerregistrationresult",
  "id": "my_trigger",
  "trigger_type": "nonexistent_type",
  "function_id": "my_function",
  "error": {
    "code": "trigger_type_not_found",
    "message": "No trigger type registered with ID 'nonexistent_type'"
  }
}

Function Not Found

Request:

{
  "type": "registertrigger",
  "id": "my_trigger",
  "trigger_type": "http",
  "function_id": "nonexistent_function",
  "config": {
    "path": "/test"
  }
}

Error Response:

{
  "type": "triggerregistrationresult",
  "id": "my_trigger",
  "trigger_type": "http",
  "function_id": "nonexistent_function",
  "error": {
    "code": "function_not_found",
    "message": "No function registered with ID 'nonexistent_function'"
  }
}

Invalid Configuration

Request:

{
  "type": "registertrigger",
  "id": "cron_trigger",
  "trigger_type": "cron",
  "function_id": "my_function",
  "config": {
    "schedule": "invalid cron expression"
  }
}

Error Response:

{
  "type": "triggerregistrationresult",
  "id": "cron_trigger",
  "trigger_type": "cron",
  "function_id": "my_function",
  "error": {
    "code": "invalid_config",
    "message": "Invalid cron expression: 'invalid cron expression'"
  }
}

Duplicate Trigger ID

Error Response:

{
  "type": "triggerregistrationresult",
  "id": "existing_trigger",
  "trigger_type": "http",
  "function_id": "my_function",
  "error": {
    "code": "duplicate_trigger_id",
    "message": "A trigger with ID 'existing_trigger' is already registered"
  }
}

Notes

• Trigger IDs must be unique within a worker session
• The function must be registered before registering a trigger for it
• The trigger type must be registered (via RegisterTriggerType) before use
• Configuration structure is specific to each trigger type
• Successful registration returns a result without an error field
• Failed registration returns a result with an error field and no exception is thrown