Custom Errors

[PythonFZ]

ZnTrack should raise custom errors such as NodeLoadingError

[PythonFZ]

Currently there are at least the following issues given the following Node:

from zntrack import Node, zn

class WriteNumber(Node):
    input = zn.params()
    output = zn.outs()
    
    def run(self):
        self.output = self.input

No Graph written yet

When no dvc.yaml etc. exist the following issues occur:

print(empty_obj = WriteNumber["not-existend"])
# <main.WriteNumber object at 0x151794868550>(name=not-existend)

it should print some more information on the state of the Node. E.g. if the parameters could be read, outputs could be read, queued, git revision, ...

empty_obj.input # raises FileNotFoundError    
empty_obj.output# raises FileNotFoundError    

both of these should raise different errors! Maybe ParamterNotAvailable and OutputsNotAvailable or InvalidStateError

If the graph is written but not executed it the outputs are not available and should raise the same error.

empty_obj.output# raises FileNotFoundError