Improved exception handling

cs3client/auth.py

@@ -17,7 +17,7 @@
 from cs3.rpc.v1beta1.code_pb2 import CODE_OK
 
 from .cs3client import CS3Client
-from .exceptions.exceptions import AuthenticationException, SecretNotSetException
+from .exceptions import AuthenticationException, SecretNotSetException
 from .config import Config
 
 

cs3client/exceptions/__init__.py

@@ -0,0 +1,74 @@
+"""
+exceptions
+
+Custom exception classes for the CS3 client.
+Where applicable, the default values correspond to the Linux standard error strings.
+
+Authors: Rasmus Welander, Diogo Castro, Giuseppe Lo Presti.
+Emails: [email protected], [email protected], [email protected]
+Last updated: 01/08/2024
+"""
+
+
+class AuthenticationException(Exception):
+    """
+    Standard error thrown when attempting an operation without the required access rights
+    """
+
+    def __init__(self, message: str = "Operation not permitted"):
+        super().__init__(message)
+
+
+class NotFoundException(IOError):
+    """
+    Standard file missing message
+    """
+
+    def __init__(self, message: str = "No such file or directory"):
+        super().__init__(message)
+
+
+class SecretNotSetException(Exception):
+    """
+    Standard file missing message
+    """
+
+    def __init__(self, message: str = "Secret was not set, unable to authenticate"):
+        super().__init__(message)
+
+
+class FileLockedException(IOError):
+    """
+    Standard error thrown when attempting to overwrite a file/xattr with a mistmatched lock,
+    or when a lock operation cannot be performed because of failed preconditions
+    """
+
+    def __init__(self, message: str = "Lock mismatch"):
+        super().__init__(message)
+
+
+class UnknownException(Exception):
+    """
+    Standard exception to be thrown when we get an error that is unknown, e.g. not defined in the cs3api
+    """
+
+    def __init__(self, message: str = ""):
+        super().__init__(message)
+
+
+class AlreadyExistsException(IOError):
+    """
+    Standard error thrown when attempting to create a resource that already exists
+    """
+
+    def __init__(self, message: str = "File exists"):
+        super().__init__(message)
+
+
+class UnimplementedException(Exception):
+    """
+    Standard error thrown when attempting to use a feature that is not implemented
+    """
+
+    def __init__(self, message: str = "Not implemented"):
+        super().__init__(message)

cs3client/file.py

@@ -20,7 +20,7 @@
 
 
 from .config import Config
-from .exceptions.exceptions import AuthenticationException, FileLockedException
+from .exceptions import AuthenticationException, FileLockedException
 from .cs3resource import Resource
 from .statuscodehandler import StatusCodeHandler
 
@@ -86,7 +86,7 @@ def set_xattr(self, auth_token: tuple, resource: Resource, key: str, value: str,
         :raises: UnknownException (Unknown error)
         """
         md = cs3spr.ArbitraryMetadata()
-        md.metadata.update({key: value})  # pylint: disable=no-member
+        md.metadata.update({key: str(value)})  # pylint: disable=no-member
         req = cs3sp.SetArbitraryMetadataRequest(ref=resource.ref, arbitrary_metadata=md, lock_id=lock_id)
         res = self._gateway.SetArbitraryMetadata(request=req, metadata=[auth_token])
         # CS3 storages may refuse to set an xattr in case of lock mismatch: this is an overprotection,
@@ -170,8 +170,7 @@ def touch_file(self, auth_token: tuple, resource: Resource) -> None:
         self._log.debug(f'msg="Invoked TouchFile" trace="{res.status.trace}"')
 
     def write_file(
-            self, auth_token: tuple, resource: Resource, content: Union[str, bytes], size: int,
-            lock_md: tuple = ('', '')
+            self, auth_token: tuple, resource: Resource, content: Union[str, bytes], size: int, lock_md: tuple = None
     ) -> None:
         """
         Write a file using the given userid as access token. The entire content is written
@@ -183,14 +182,16 @@ def write_file(
         :param resource: Resource to write content to
         :param content: content to write
         :param size: size of content (optional)
-        :param lock_md: tuple (<app_name>, <lock_id>)
+        :param lock_md: tuple (<app_name>, <lock_id>) (optional)
         :return: None (Success)
         :raises: FileLockedException (File is locked),
         :raises: AuthenticationException (Authentication failed)
         :raises: UnknownException (Unknown error)
 
         """
-        app_name, lock_id = lock_md
+        app_name = lock_id = ''
+        if lock_md:
+            app_name, lock_id = lock_md
         tstart = time.time()
         # prepare endpoint
         if size == -1:
@@ -228,7 +229,7 @@ def write_file(
                     "X-Reva-Transfer": protocol.token,
                     **dict([auth_token]),
                     "X-Lock-Id": lock_id,
-                    "X-Lock_Holder": app_name,
+                    "X-Lock-Holder": app_name,
                 }
             putres = requests.put(
                 url=protocol.upload_endpoint,

cs3client/statuscodehandler.py

@@ -10,7 +10,7 @@
 import cs3.rpc.v1beta1.code_pb2 as cs3code
 import cs3.rpc.v1beta1.status_pb2 as cs3status
 
-from .exceptions.exceptions import AuthenticationException, NotFoundException, \
+from .exceptions import AuthenticationException, NotFoundException, \
     UnknownException, AlreadyExistsException, FileLockedException, UnimplementedException
 from .config import Config
 
@@ -75,31 +75,23 @@ def handle_errors(self, status: cs3status.Status, operation: str, msg: str = Non
 
         if status.code == cs3code.CODE_FAILED_PRECONDITION or status.code == cs3code.CODE_ABORTED:
             self._log_precondition_info(status, operation, status_message, msg)
-            raise FileLockedException(f'Failed precondition: operation="{operation}" '
-                                      f'status_code="{status.code}"  message="{status.message}"')
+            raise FileLockedException
         if status.code == cs3code.CODE_ALREADY_EXISTS:
             self._log_already_exists(status, operation, status_message, msg)
-            raise AlreadyExistsException(f'Resource already exists: operation="{operation}" '
-                                         f'status_code="{status.code}" message="{status.message}"')
+            raise AlreadyExistsException
         if status.code == cs3code.CODE_UNIMPLEMENTED:
             self._log.info(f'msg="Invoked {operation} on unimplemented feature" ')
-            raise UnimplementedException(f'Unimplemented feature: operation="{operation}" '
-                                         f'status_code="{status.code}" message="{status.message}"')
+            raise UnimplementedException
         if status.code == cs3code.CODE_NOT_FOUND:
             self._log_not_found_info(status, operation, status_message, msg)
-            raise NotFoundException(f'Not found: operation="{operation}" '
-                                    f'status_code="{status.code}" message="{status.message}"')
+            raise NotFoundException
         if status.code == cs3code.CODE_UNAUTHENTICATED:
             self._log_authentication_error(status, operation, status_message, msg)
-            raise AuthenticationException(f'Operation not permitted: operation="{operation}" '
-                                          f'status_code="{status.code}" message="{status.message}"')
+            raise AuthenticationException
         if status.code != cs3code.CODE_OK:
             if "path not found" in str(status.message).lower():
                 self._log.info(f'msg="Invoked {operation} on missing file" ')
-                raise NotFoundException(
-                    message=f'No such file or directory: operation="{operation}" '
-                            f'status_code="{status.code}" message="{status.message}"'
-                )
+                raise NotFoundException
             self._log_unknown_error(status, operation, status_message, msg)
             raise UnknownException(f'Unknown Error: operation="{operation}" status_code="{status.code}" '
                                    f'message="{status.message}"')

docs/source/exceptions.rst

@@ -1,7 +1,7 @@
 exceptions Module
 =================
 
-.. automodule:: exceptions.exceptions
+.. automodule:: exceptions
    :members:
    :undoc-members:
    :show-inheritance:

tests/test_app.py

@@ -12,7 +12,7 @@
 from unittest.mock import Mock, patch
 import pytest
 
-from cs3client.exceptions.exceptions import (
+from cs3client.exceptions import (
     AuthenticationException,
     NotFoundException,
     UnknownException,

tests/test_checkpoint.py

@@ -12,7 +12,7 @@
 import pytest
 import cs3.rpc.v1beta1.code_pb2 as cs3code
 
-from cs3client.exceptions.exceptions import (
+from cs3client.exceptions import (
     AuthenticationException,
     NotFoundException,
     UnknownException,

tests/test_file.py

@@ -13,7 +13,7 @@
 import cs3.rpc.v1beta1.code_pb2 as cs3code
 
 from cs3client.cs3resource import Resource
-from cs3client.exceptions.exceptions import (
+from cs3client.exceptions import (
     AuthenticationException,
     NotFoundException,
     FileLockedException,

tests/test_share.py

@@ -15,7 +15,7 @@
 import cs3.storage.provider.v1beta1.resources_pb2 as cs3spr
 import cs3.rpc.v1beta1.code_pb2 as cs3code
 
-from cs3client.exceptions.exceptions import (
+from cs3client.exceptions import (
     AuthenticationException,
     NotFoundException,
     UnknownException,

tests/test_user.py

@@ -12,7 +12,7 @@
 from unittest.mock import Mock, patch
 import cs3.rpc.v1beta1.code_pb2 as cs3code
 
-from cs3client.exceptions.exceptions import (
+from cs3client.exceptions import (
     AuthenticationException,
     NotFoundException,
     UnknownException,