Message is the input and output data or events of the rule chain. It can be transformed, filtered and distributed by the node components. It contains the following content:

• Ts: Type: int64, the timestamp of the message generation
• Id: Type: string, message ID, the same message in the rule engine circulation, the whole process is unique
• DataType: Type: string, value: JSON, TEXT, BINARY, default value: JSON. If it is JSON type, it will be automatically converted to an object in the script component, and you can directly operate the json field.
• Type: Type: string, message type. Rule node components can route by this field.
• Data: Type: string, message content
• Metadata: Type: map[string]string, message metadata.