fix(api): chain original exception in 13 except blocks per PEP 3134 (#40738)

Co-authored-by: Harsh Kashyap <Harsh23Kashyap@users.noreply.github.com>

api/core/plugin/backwards_invocation/app.py

@@ -270,8 +270,8 @@ class PluginAppBackwardsInvocation(BaseBackwardsInvocation):
                 app = session.scalar(select(App).where(App.id == app_id, App.tenant_id == tenant_id).limit(1))
                 if app:
                     session.expunge(app)
-        except Exception:
-            raise ValueError("app not found")
+        except Exception as e:
+            raise ValueError("app not found") from e
 
         if not app:
             raise ValueError("app not found")

api/core/plugin/entities/parameters.py

@@ -241,8 +241,10 @@ def cast_parameter_value(typ: StrEnum, value: Any, /):
                 return str(value)
     except ValueError:
         raise
-    except Exception:
-        raise ValueError(f"The tool parameter value {repr(value)} is not in correct type of {as_normal_type(typ)}.")
+    except Exception as e:
+        raise ValueError(
+            f"The tool parameter value {repr(value)} is not in correct type of {as_normal_type(typ)}."
+        ) from e
 
 
 def init_frontend_parameter(rule: PluginParameter, type: StrEnum, value: Any):

api/core/plugin/impl/base.py

@@ -276,19 +276,19 @@ class BasePluginClient:
                 json_response = transformer(json_response)
             # https://stackoverflow.com/questions/59634937/variable-foo-class-is-not-valid-as-type-but-why
             rep = PluginDaemonBasicResponse[type_].model_validate(json_response)  # type: ignore
-        except Exception:
+        except Exception as e:
             msg = (
                 f"Failed to parse response from plugin daemon to PluginDaemonBasicResponse [{str(type_.__name__)}],"
                 f" url: {path}"
             )
             logger.exception(msg)
-            raise ValueError(msg)
+            raise ValueError(msg) from e
 
         if rep.code != 0:
             try:
                 error = PluginDaemonError.model_validate(json.loads(rep.message))
-            except Exception:
-                raise ValueError(f"{rep.message}, code: {rep.code}")
+            except Exception as e:
+                raise ValueError(f"{rep.message}, code: {rep.code}") from e
 
             self._handle_plugin_daemon_error(error.error_type, error.message)
         if rep.data is None:

api/core/rag/retrieval/output_parser/structured_chat.py

@@ -19,5 +19,5 @@ class StructuredChatOutputParser:
                     return ReactAction(response["action"], response.get("action_input", {}), text)
             else:
                 return ReactFinish({"output": text}, text)
-        except Exception:
-            raise ValueError(f"Could not parse LLM output: {text}")
+        except Exception as e:
+            raise ValueError(f"Could not parse LLM output: {text}") from e