generator

Periodically generates messages with configurable content and timing.

Configuration

Generation parameters

• Generated messages limit: Number of messages to generate before stopping. Set to 0 for unlimited message generation.
• Generation frequency in seconds: Time interval between message generations in seconds.

Originator

Specifies the originator entity for generated messages. The configuration depends on the selected entity type:

• Type: The entity type that will be set as the originator of generated messages. Supported types include:
  • Device
  • Asset
  • Entity View
  • Current Tenant
  • Customer
  • User
  • Dashboard
  • Edge
  • Current Rule Node
  • Converter
  • Integration
  • Scheduler Event
  • Blob Entity
  • Role
  • Entity Group

Configuration by originator type:

• Current Tenant / Current Rule Node: No additional configuration required. Uses the current tenant or the generator node itself as the originator.

• Entity Group: Requires additional group configuration:
  • Group Owner: The owner of the group
  • Entity Type: The type of entities contained within the group
  • Group: The specific entity group to use
• All other types: Requires selecting the specific entity to use as the originator.

Generator function

The code entered into the script editor acts as the body of a generator function. This function implicitly receives three arguments that are available as variables in your script:

• prevMsg - the data of the previously generated message, typically as a JSON object.
• prevMetadata - the metadata of the previously generated message, as a key-value object where all values are strings.
• prevMsgType - the type of the previously generated message, as a string.

For the very first generated message, when no previous message exists:

• prevMsg will be an empty JSON object {}
• prevMetadata will be an empty JSON object {}
• prevMsgType will be an empty string ""

The function must return an object containing the following keys:

• msg - the data for the new outgoing message.
• metadata - the metadata for the new message.
• msgType - the type for the new message.

Queue

• Queue: Selects the queue where the generated message will be placed for persistence and durability. The “Main” queue is used when not selected.

JSON Schema

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{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "TbMsgGeneratorNodeConfiguration",
  "type": "object",
  "properties": {
    "msgCount": {
      "type": "integer",
      "description": "Number of messages to generate (0 = unlimited)"
    },
    "periodInSeconds": {
      "type": "integer",
      "description": "Generation frequency in seconds"
    },
    "originatorId": {
      "type": "string",
      "description": "ID of the originator entity"
    },
    "originatorType": {
      "type": "string",
      "enum": [
        "DEVICE",
        "ASSET",
        "ENTITY_VIEW",
        "TENANT",
        "CUSTOMER",
        "USER",
        "DASHBOARD",
        "EDGE",
        "RULE_NODE",
        "CONVERTER",
        "INTEGRATION",
        "SCHEDULER_EVENT",
        "BLOB_ENTITY",
        "ROLE",
        "ENTITY_GROUP"
      ],
      "description": "Type of the originator entity"
    },
    "scriptLang": {
      "type": "string",
      "enum": [
        "TBEL",
        "JS"
      ],
      "description": "Script language for generator function"
    },
    "jsScript": {
      "type": "string",
      "description": "JavaScript generator function"
    },
    "tbelScript": {
      "type": "string",
      "description": "TBEL generator function"
    }
  }
}

Message processing algorithm

The generator node operates independently of incoming messages, meaning it does not accept messages from other rule nodes (only self-scheduled messages trigger generation). The processing follows this cycle:

1. Node receives a self-scheduled GENERATOR_NODE_SELF_MSG message
2. Executes the generator function with access to previous generated message
3. Creates a new message with:
   • Originator set to the configured entity
   • Data, metadata, and type from script execution result
4. Routes the generated message through the Success connection
5. If message count limit not reached, schedules the next generation cycle
6. Increments the current message count

Output connections

• Success
  • Generated messages
• Failure
  • Self-scheduled message if generator script fails or another unexpect error occurs during generation

Examples

Example 1 — Basic daily message generation

Node configuration

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{
  "msgCount": 0,
  "periodInSeconds": 86400,
  "originatorType": "RULE_NODE",
  "scriptLang": "TBEL",
  "tbelScript": "var msg = {};\nvar metadata = {};\nvar msgType = \"CUSTOM\";\n\nreturn { msg: msg, metadata: metadata, msgType: msgType };"
}

Generated message

Type: CUSTOM

Data:

1
{}

Metadata:

1
{}

Originator: RULE_NODE (the generator node itself)

Result

Once per day (every 86400 seconds), the node generates an empty message, running indefinitely.

Example 2 — Sequential counter messages

Node configuration

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{
  "msgCount": 3,
  "periodInSeconds": 60,
  "originatorType": "DEVICE",
  "originatorId": "3bc2eb60-8d77-11f0-8a6c-59050cd4204f",
  "scriptLang": "TBEL",
  "tbelScript": "var counter = 1;\nif (!prevMsg.isEmpty()) {\n    counter = prevMsg.counter + 1;\n}\n\nvar msg = {\n    counter: counter\n};\n\nvar metadata = {};\nvar msgType = \"POST_TELEMETRY_REQUEST\";\n\nreturn { msg: msg, metadata: metadata, msgType: msgType };"
}

Outgoing messages

1st message

Type: POST_TELEMETRY_REQUEST

Data:

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{
  "counter": 1
}

Originator: DEVICE with ID 3bc2eb60-8d77-11f0-8a6c-59050cd4204f

2nd message

Type: POST_TELEMETRY_REQUEST

Data:

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{
  "counter": 2
}

Originator: DEVICE with ID 3bc2eb60-8d77-11f0-8a6c-59050cd4204f

3rd message

Type: POST_TELEMETRY_REQUEST

Data:

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{
  "counter": 3
}

Originator: DEVICE with ID 3bc2eb60-8d77-11f0-8a6c-59050cd4204f

Result

The node generates exactly 3 messages, one per minute, with a counter field that increments from 1 to 3, then stops.