tag.get(propertyObject) not working

Ignition
1

Hello all,
I have been attempting to pull specific properties out of tags that are returned by system.tag.browseConfiguration().
Following the post here I made the following script:

"""
This example will browse the root of the Tag Provider named "default".
For each tag found, prints the non-default properties.
"""
from com.inductiveautomation.ignition.common.sqltags.model import TagProp
# Specify the folder to browse. Modify this line to filter on a specific folder. 
folderPath = "CF1/CF1_BowlSpeed"
db = TagProp.HistoricalDeadband
histEnabled = TagProp.HistoryEnabled
# Start a non-recursive browse, and stores the configuration data in a variable
tagConfig = system.tag.browseConfiguration(folderPath, False)
# Iterate through the configuration data
for tag in tagConfig:
    #print "--------------------------------------------------------------------"
    propList = tag.getProperties()
    print "Property '%s' has a value of '%s'" % (str(db), tag.get(db))
    print "Property '%s' has a value of '%s'" % (str(histEnabled), tag.get(histEnabled))
    # Iterate through the list of properties
    for prop in propList:
        #Print the property name and value.
        if prop == db:
        	print "Property '%s' has a value of '%s'" % (prop, tag.get(prop))
        elif prop == histEnabled:
        	print "Property '%s' has a value of '%s'" % (prop, tag.get(prop))

The output is the following:

Property 'HistoricalDeadband' has a value of 'None'
Property 'HistoryEnabled' has a value of 'None'
Property 'HistoricalDeadband' has a value of '15.0'
Property 'HistoryEnabled' has a value of 'True'

My question is how is it that one method returns ‘None’ while the other method returns a value?
I would really like to pull the exact properties I want and not depend on the getProperties() method.
Thanks

2

Hmm. Good question :confused:

I think basically the Property objects you get from the TagProp enum don’t implement equality the way a Property should, so when you call get with it on the PropertySet (each TagConfiguration is a PropertySet) it doesn’t find it as a key. Seems like a bug on our side.

3

Try using properties from com.inductiveautomation.ignition.common.tags.config.TagConfigProps instead of the TagProp enum you’re using.

1 Like
4

That fixed it. Can you please give me a link to that in the API docs. I can only find com.inductiveautomation.ignition.common.sqltags.* and not the specific class you listed. I'm probably just not looking in the right place.

5

There’s no API docs to link you to, as far as I know…

It’s part of the same JAR file as the TagProp enum, so you should be able to find it by its class name if it has docs.

6

It does not unfortunately.
But it seems that all of the properties I have tried so far that are in the class TagProp have worked. Thanks for your help!

7

Turns out the members of the original TagProp enum each have .property() method you can call to get a usable Property as well.

8

Okay. I’m trying to pull out the historical scanclass for each tag configuration, but I get the following error:

Traceback (most recent call last):

  File "<event:mousePressed>", line 1, in <module>
  File "<custom-function updateTable>", line 44, in updateTable
TypeError: getOrDefault(): 1st arg can't be coerced to com.inductiveautomation.ignition.common.config.Property

Ignition v7.9.5 (b2017111615)
Java: Oracle Corporation 1.8.0_151

Here is the relevant code:

	from com.inductiveautomation.ignition.common.sqltags.model import TagProp
	from com.inductiveautomation.ignition.common.tags.config import TagConfigProps
	from com.inductiveautomation.ignition.common.config import Property
	# Specify the folder to browse. Modify this line to filter on a specific folder. 
	propDict = {}
	propList = []
	folderPaths = ["aMemoryTags"]
	headers = ["Tag Path","Documentation","Data Type","Engineering Unit","History Enabled","Historical Deadband","Historical Scanclass","Engineering Low", "Engineering High"]
	db = TagConfigProps.HistoricalDeadband
	histSC = TagConfigProps.HistoricalScanclass
	histEnabled = TagConfigProps.HistoryEnabled
	engLow = TagConfigProps.EngLow
	engHigh = TagConfigProps.EngHigh
	engUnit = TagConfigProps.EngUnit
	dataType = TagConfigProps.DataType
	documentation = TagConfigProps.Documentation
	print Property.isInstance(TagProp)
	print Property.isInstance(TagConfigProps)
	# Start a non-recursive browse, and stores the configuration data in a variable
	for folderPath in folderPaths:
		tagConfig = system.tag.browseConfiguration(folderPath, False)
		# Iterate through the configuration data
		for tag in tagConfig:
		    #print "--------------------------------------------------------------------"
		    path = tag.getFullPath()
		    doc = tag.getOrDefault(documentation)
		    type = tag.getOrDefault(dataType)
		    unit = tag.getOrDefault(engUnit)
		    #print "Tag Path = '%s'" % (tag.getFullPath())
		    deadBand = tag.getOrDefault(db)
		    histSC = tag.getOrDefault(histSC)#histSC)
		    #print "Property '%s' has a value of '%s'" % (str(db), tag.getOrDefault(db))
		    hist = tag.getOrDefault(histEnabled)
		    #print "Property '%s' has a value of '%s'" % (str(histEnabled), tag.getOrDefault(histEnabled))
		    low = tag.getOrDefault(engLow)
		    #print "Property '%s' has a value of '%s'" % (str(engLow), tag.getOrDefault(engLow))
		    high = tag.getOrDefault(engHigh)
		    #print "Property '%s' has a value of '%s'" % (str(engHigh), tag.getOrDefault(engHigh))
		    if hist == True:
		    	propDict[path] = [doc,type,unit,hist,deadBand,histSC,low,high]
		    # Iterate through the list of propDict
		#print propDict.keys()
	    
	sortKeys = sorted(propDict)
	for key in sortKeys:
		#print key
		values = propDict.get(key)
		propList.append([key,values[0],values[1],values[2],values[3],values[4],values[5],values[6],values[7]])
	#for prop in propList:
	#	print prop
	ds = system.dataset.toDataSet(headers,propList)
	self.getComponent('Power Table').data = ds

The problem occurs on the line: histSC = tag.getOrDefault(histSC)#histSC)
My best guess is this is a bug, but I want to see if I am doing something wrong in referencing this property.

Thanks.

9

The property reference is fine, but after processing the first tag in the tagConfig you’re clobbering your histSC variable with something that isn’t a Property any more.

10

:sweat_smile: oops… Thanks Kevin.

11

Hi @Kevin.Herron

If i try to use now
from com.inductiveautomation.ignition.common.tags.config import TagConfigProps

error
ImportError: cannot import name TagConfigProps

i am using ignition 8.1.17

I am trying get the history enabled or not using - system.tag.browse

can you help me how to get it