How to get the path/location of a transformer like the log files do?

I got a partial solution figured out but it feels like a bit of a hack and it could easily break in future versions of FME. It would be fantastic if Safe could make an official Python API call to get this information.

The solution relies on a call to feature.getFeatureType() inside a Python caller. This call will return the name of the previous transformer plus it’s output port, plus (sometimes but not always) some random FME identifier. If the transformer is inside a custom transformer then the ct name is prepended, just like in the log files.

e.g. MyCustomTransformer_HTTPCaller_<REJECTED>_1_3kjhdD3

There are two problems with this solution:

1. You can’t turn it into a custom transformer because then you will always get the name of the custom transformer itself (not the previous transformer outside the custom transformer).
2. You need to hard-code the name of the output port from the previous transformer into the Python code. If you don’t care about removing the port name from the result then I guess it doesn’t matter.

Here’s the code:

   def input(self, feature):

      # Set the name of the output port from the previous transformer that's

      # connected to this PythonCaller.

      connected_port_name = 'Input'

       

      ft = feature.getFeatureType()

      portName_idx = ft.rfind(f'_{connected_port_name}')

      if portName_idx != -1:

         ft = ft[0:portName_idx] # remove the port name from the end of the transformer name

      feature.setAttribute("_transformer_name",ft)

      self.pyoutput(feature)