Handle CTI load failures and track failed files

Treat failed CTI loads as a mapping of CTI->error and record failures when initializing the shared Harvester. gentl_discovery.py now logs exceptions, captures failed_files as a dict, and raises a runtime error if no CTI producers were successfully loaded; it also attaches loaded_files and failed_files to raised exceptions and attempts to reset the harvester. gentl_backend.py updated to consume failed_files as a dict (using .items()) when building reporting data. Added a helper to reset the harvester and propagate context for callers.

Author: C-Achard

dlclivegui/cameras/backends/gentl_backend.py

@@ -565,11 +565,13 @@ def _acquire_shared_harvester(self, loaded: list[str]) -> list:
             self._harvester = self._shared_entry.harvester
 
             actual_loaded = list(getattr(self._shared_entry, "loaded_files", loaded))
-            actual_failed = list(getattr(self._shared_entry, "failed_files", []))
+            actual_failed = dict(getattr(self._shared_entry, "failed_files", {}))
 
             ns["cti_files_loaded"] = actual_loaded
             if actual_failed:
-                ns["cti_files_failed"] = [{"cti": str(cti), "error": str(error)} for cti, error in actual_failed]
+                ns["cti_files_failed"] = [
+                    {"cti": str(cti), "error": str(error)} for cti, error in actual_failed.items()
+                ]
 
             with self._shared_entry.lock:
                 infos = list(self._harvester.device_info_list or [])
@@ -583,11 +585,11 @@ def _acquire_shared_harvester(self, loaded: list[str]) -> list:
 
         except Exception as exc:
             exc_loaded = list(getattr(exc, "loaded_files", []))
-            exc_failed = list(getattr(exc, "failed_files", []))
+            exc_failed = dict(getattr(exc, "failed_files", {}))
 
             if exc_loaded or exc_failed:
                 ns["cti_files_loaded"] = [str(p) for p in exc_loaded]
-                ns["cti_files_failed"] = [{"cti": str(cti), "error": str(error)} for cti, error in exc_failed]
+                ns["cti_files_failed"] = [{"cti": str(cti), "error": str(error)} for cti, error in exc_failed.items()]
 
             if self._shared_entry is not None:
                 try:

dlclivegui/cameras/backends/utils/gentl_discovery.py

@@ -5,6 +5,7 @@
 from __future__ import annotations
 
 import glob
+import logging
 import os
 import threading
 from collections.abc import Iterable, Sequence
@@ -24,6 +25,8 @@ class GenTLDiscoveryPolicy(Enum):
 except Exception:  # pragma: no cover - optional dependency
     Harvester = None  # type: ignore
 
+logger = logging.getLogger(__name__)
+
 
 class SharedHarvesterEntry:
     """
@@ -41,13 +44,34 @@ def __init__(self, cti_files: list[str]):
         self.refcount = 0
         self.harvester = Harvester()
         self.loaded_files: list[str] = []
+        self.failed_files: dict[str, str] = {}
 
         for cti in self.key:
-            self.harvester.add_file(cti)
-            self.loaded_files.append(cti)
+            try:
+                self.harvester.add_file(cti)
+                self.loaded_files.append(cti)
+            except Exception as e:
+                logger.exception(f"Failed to load CTI file: {cti}. Skipping.")
+                self.failed_files[cti] = str(e)
+
+        if not self.loaded_files:
+            e = RuntimeError("No GenTL producer (.cti) could be loaded by shared Harvester.")
+            self._raise_and_reset_harvester(e)
 
         # Initial device enumeration.
-        self.harvester.update()
+        try:
+            self.harvester.update()
+        except Exception as e:
+            self._raise_and_reset_harvester(e)
+
+    def _raise_and_reset_harvester(self, exc: Exception) -> None:
+        exc.loaded_files = self.loaded_files[:]
+        exc.failed_files = dict(self.failed_files)
+        try:
+            self.harvester.reset()
+        except Exception:
+            pass
+        raise exc
 
 
 class SharedHarvesterPool: