When raising an exception during exception handling, chain them together for slightly cleaner logs

src/documents/classifier.py

@@ -101,8 +101,8 @@ class DocumentClassifier:
                         self.correspondent_classifier = pickle.load(f)
                         self.document_type_classifier = pickle.load(f)
                         self.storage_path_classifier = pickle.load(f)
-                    except Exception:
-                        raise ClassifierModelCorruptError()
+                    except Exception as err:
+                        raise ClassifierModelCorruptError() from err
 
             # Check for the warning about unpickling from differing versions
             # and consider it incompatible

src/documents/consumer.py

@@ -78,10 +78,16 @@ class Consumer(LoggingMixin):
             {"type": "status_update", "data": payload},
         )
 
-    def _fail(self, message, log_message=None, exc_info=None):
+    def _fail(
+        self,
+        message,
+        log_message=None,
+        exc_info=None,
+        exception: Optional[Exception] = None,
+    ):
         self._send_progress(100, 100, "FAILED", message)
         self.log("error", log_message or message, exc_info=exc_info)
-        raise ConsumerError(f"{self.filename}: {log_message or message}")
+        raise ConsumerError(f"{self.filename}: {log_message or message}") from exception
 
     def __init__(self):
         super().__init__()
@@ -152,6 +158,7 @@ class Consumer(LoggingMixin):
                 MESSAGE_PRE_CONSUME_SCRIPT_ERROR,
                 f"Error while executing pre-consume script: {e}",
                 exc_info=True,
+                exception=e,
             )
 
     def run_post_consume_script(self, document):
@@ -217,6 +224,7 @@ class Consumer(LoggingMixin):
                 MESSAGE_POST_CONSUME_SCRIPT_ERROR,
                 f"Error while executing post-consume script: {e}",
                 exc_info=True,
+                exception=e,
             )
 
     def try_consume_file(
@@ -331,6 +339,7 @@ class Consumer(LoggingMixin):
                 str(e),
                 f"Error while consuming document {self.filename}: {e}",
                 exc_info=True,
+                exception=e,
             )
 
         # Prepare the document classifier.
@@ -415,6 +424,7 @@ class Consumer(LoggingMixin):
                 f"The following error occurred while consuming "
                 f"{self.filename}: {e}",
                 exc_info=True,
+                exception=e,
             )
         finally:
             document_parser.cleanup()