Deriving UDT Tag Provider using a Tag Event Script

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Recently I ran into a situation where I found that it would be required to have a tags provider be stored in a UDT as meta data. At first I thought to use the {PathToParentFolder} built in parameter however this did not work as it does not include the tags provider.

I ended up discovering that relative tag paths not only work in UDT Expressions but also UDT Scripts. Knowing this I was able to make the following Tag Event Script that writes the Tag Provider to the (string) UDT Member Tag (Memory - String) that it is bound to:

if initialChange:
	# retrieve configuration for relative tag provider
	config = system.tag.getConfiguration('[~]', False)
		
	# retrieve the actual path and set the tag value
	system.tag.writeAsync([tagPath], [config[0]['path']])

The system.tag.getConfiguration() built in function (without the recursive boolean flag set) returns a list of python dictionaries containing tag configuration information for the provided path.

In this case since we are providing only a tag provider ([~] is relative to the Tag provider of the Tag that is being bound) this function will always return a list containing one dictionary containing 2 keys. One of these keys is path which holds full path for the tag provider.

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