Convert CIM Object to JSON string

Question

I'm writing a script to generate a UniqueValueRenderer from scratch using

arcpy.cim.CreateCIMObjectFromClassName('CIMUniqueValueRenderer','V3')

Since this object contains a lot of other CIM objects, I have to make all those as well, but somewhere in there I'm missing something so when writing it into the layer definition, Pro will crash.

Is there a way I can take my newly created CIMUniqueValueRenderer object and convert it to a JSON string so I can see what it contains?

I found a reference to a function GetJSONForCIMObject in another post, but can find no such function in the ArcPy documentation.

abaldenweck@blm.gov_BLM_EGIS · Answer

There's a certain irony in how much I've revisited this page over the last two weeks to remind myself of how to get this information.

Hard agree on the notebook. Huge pain.

Pukawai · Answer

Thank you for this! With some massaging of that output string I should be able to compare it to a .lyrx file and discover what's missing.  Now, if only intellisense worked in notebooks....

abaldenweck@blm.gov_BLM_EGIS · Answer

Well, that's kind of the problem with CIM. Arcane and not well documented.

x = arcpy.cim.CreateCIMObjectFromClassName('CIMUniqueValueRenderer','V3')
y = arcpy.cim.GetJSONForCIMObject(x, 'V3')
print(y)

'''
{"sampleSize": 10000, "visualVariables": [], 
"colorRamp": {"colorSpace": {"type": "CIMColorSpace"}, "type": "CIMColorRamp"}, 
"defaultSymbol": {"primitiveOverrides": [], 
"symbol": {"type": "CIMSymbol"}, 
"minScale": 0.0, "maxScale": 0.0, 
"scaleDependentSizeVariation": [], 
"minDistance": 0.0, "maxDistance": 0.0, 
"type": "CIMSymbolReference"}, 
"defaultSymbolPatch": "Default", 
"fields": [], "groups": [], 
"useDefaultSymbol": false, 
"valueExpressionInfo": {"returnType": "Default", "type": "CIMExpressionInfo"}, 
"polygonSymbolColorTarget": "Fill", 
"authoringInfo": {"type": "CIMUniqueValueRendererAuthoringInfo"}, "type": "CIMUniqueValueRenderer"}
'''

Honestly I check out the CIM's github reference and then spend a lot of time using the intellisense in the Python Window in Pro to figure out what I can do. Honestly I hadn't heard of that function before today.