Meta messages

Meta messages can be used to write or edit the attributes/properties of MQTT value items existing in APIS environment.

A meta message is a JSON object that contains the following keys:

• Message type
• Payload

Payload is the content of the message. It is an array of JSON objects for value items containing the properties which need to be written/edited as the keys in its key:value pairs.

While trying to edit any attribute of an item, make sure that it's writable and that the key of the value item is provided. Index or id should be taken as a value for properties that have a dropdown menu or list to select from.

Meta Example

	{
		"messagetype" : "meta",
		"version" : 1,
		"payload": 
			[
				{
                    			"k" : "Tag1",
                    			"eu": 105,
                    			"description": "Description for tag 1",

				},

				{
                    			"k": "Tag2",
                    			"Offset": 100,

				},

				{
                    			"k": "Tag3",
                    			"AlmPrimaryArea": "AlarmArea1",
                    			"AlmLL": 0,
                    			"AlmL": 100,
                    			"AlmH": 200,
                    			"AlmHH": 350,
                    			"AlmHelp": "Help for alarm",
                    			"Logger": True,

				},

			]
	}

Mandatory Fields in message:

• Message type
• Payload
• k (key)