add graceful error handling with return of status codes, closes #12

src/dopt_sensor_anomalies/_interface.py

@@ -1,16 +1,44 @@
 """main pipeline interface for external calls"""
 
+from __future__ import annotations
+
+import sys
+from typing import TYPE_CHECKING, TextIO
+
 from dopt_sensor_anomalies import detection
 
+if TYPE_CHECKING:
+    from dopt_basics.result_pattern import Status
+
+
+def _print_error_state(
+    state: Status,
+    out_stream: TextIO,
+) -> None:
+    if state.ExceptionType is None:
+        raise RuntimeError("Tried to treat state as error, but no exception is registered")
+
+    msg = (
+        f"During the procedure the following exception occurred:"
+        f"\nType: {state.ExceptionType.__name__}\nDescription: {state.description}\n"
+        f"Message: {state.message}"
+    )
+    print(msg, flush=True, file=out_stream)
+
 
 def sensor_anomalies_detection(
     user_img_path: str,
     pixels_per_metric_X: float,
     pixels_per_metric_Y: float,
-) -> None:
+) -> int:
     res = detection.pipeline(
         user_img_path=user_img_path,
         pixels_per_metric_X=pixels_per_metric_X,
         pixels_per_metric_Y=pixels_per_metric_Y,
     )
+    if res.status.code != 0:
+        _print_error_state(res.status, out_stream=sys.stderr)
+        return 1
+
     res.unwrap()
+    return 0