PipelineStep: add try/catch and expose failing folder path on error

[paACode]

PipelineStep — wrap run() with try/catch and report failing folder path

Problem

Currently PipelineStep.run() has no error handling. When a step fails mid-way through iterating over folders, the pipeline crashes immediately with no information about which folder caused the failure.

Proposed Solution

Split run() into two methods:

• Rename the existing run() abstract method to _run() — subclasses implement this
• Add a new run() as a wrapper that handles errors and logging

from typing import final

class PipelineStep(ABC):

    def run(self) -> bool:
        """Public entry point. Wraps _run() with error handling."""
        print(f"Starting Step: {self.name} ⏳")
        try:
            self._run()
            print(f"Finished Step: {self.name} ✅")
            return True
        except Exception as e:
            print(f"Failed Step: {self.name} ❌ — {e}")
            raise

    @abstractmethod
    def _run(self) -> None:
        """Actual step logic. Subclasses implement this."""

Inside each subclass _run(), the per-folder loop should catch and re-raise with the folder path:

def _run(self) -> None:
    for input_folder, output_folder in zip(self.input_folders, self.output_folders):
        try:
            # ... step logic ...
        except Exception as e:
            raise RuntimeError(f"Failed at folder: {input_folder}") from e

Expected Output

Failed Step: BuildDigitalSurfaceModel ❌ — Failed at folder: D:/data/mjolnir/re112o_250610/02_processing

Tasks

• Rename run() → _run() in PipelineStep base class
• Add run() wrapper with try/catch to base class
• Update all subclasses: rename run() → _run() and add per-folder try/catch

Out of Scope

How the pipeline orchestrator handles step failures (skip vs. abort, retry, reporting) is not part of this issue.