Revert "Revert "refactor: move xmodule folder to root""

xmodule/modulestore/exceptions.py

@@ -0,0 +1,120 @@
+"""
+Exceptions thrown by KeyStore objects
+"""
+
+
+class ItemNotFoundError(Exception):
+    pass
+
+
+class ItemWriteConflictError(Exception):
+    pass
+
+
+class MultipleCourseBlocksFound(Exception):
+    """
+    Raise this exception when Iterating over the course blocks return multiple course blocks.
+    """
+    pass  # lint-amnesty, pylint: disable=unnecessary-pass
+
+
+class MultipleLibraryBlocksFound(Exception):
+    """
+    Raise this exception when Iterating over the library blocks return multiple library blocks.
+    """
+    pass  # lint-amnesty, pylint: disable=unnecessary-pass
+
+
+class InsufficientSpecificationError(Exception):
+    pass
+
+
+class OverSpecificationError(Exception):
+    pass
+
+
+class InvalidLocationError(Exception):
+    pass
+
+
+class NoPathToItem(Exception):
+    pass
+
+
+class ReferentialIntegrityError(Exception):
+    """
+    An incorrect pointer to an object exists. For example, 2 parents point to the same child, an
+    xblock points to a nonexistent child (which probably raises ItemNotFoundError instead depending
+    on context).
+    """
+    pass  # lint-amnesty, pylint: disable=unnecessary-pass
+
+
+class DuplicateItemError(Exception):
+    """
+    Attempted to create an item which already exists.
+    """
+    def __init__(self, element_id, store=None, collection=None):
+        super().__init__()
+        self.element_id = element_id
+        self.store = store
+        self.collection = collection
+
+    def __str__(self, *args, **kwargs):
+        """
+        Print info about what's duplicated
+        """
+        return "{store}[{collection}] already has {element_id} ({exception})".format(
+            store=self.store,
+            collection=self.collection,
+            element_id=self.element_id,
+            exception=Exception.__str__(self, *args, **kwargs),
+        )
+
+
+class VersionConflictError(Exception):
+    """
+    The caller asked for either draft or published head and gave a version which conflicted with it.
+    """
+    def __init__(self, requestedLocation, currentHeadVersionGuid):
+        super().__init__('Requested {}, but current head is {}'.format(
+            requestedLocation,
+            currentHeadVersionGuid
+        ))
+
+
+class DuplicateCourseError(Exception):
+    """
+    An attempt to create a course whose id duplicates an existing course's
+    """
+    def __init__(self, course_id, existing_entry):
+        """
+        existing_entry will have the who, when, and other properties of the existing entry
+        """
+        super().__init__(
+            f'Cannot create course {course_id}, which duplicates {existing_entry}'
+        )
+        self.course_id = course_id
+        self.existing_entry = existing_entry
+
+
+class InvalidBranchSetting(Exception):
+    """
+    Raised when the process' branch setting did not match the required setting for the attempted operation on a store.
+    """
+    def __init__(self, expected_setting, actual_setting):
+        super().__init__(f"Invalid branch: expected {expected_setting} but got {actual_setting}")  # lint-amnesty, pylint: disable=line-too-long, super-with-arguments
+        self.expected_setting = expected_setting
+        self.actual_setting = actual_setting
+
+
+class InvalidProctoringProvider(Exception):
+    """
+    Error with selected proctoring provider raised when the provided is unknown.
+    """
+
+    def __init__(self, proctoring_provider, available_providers):
+        super().__init__(f"The selected proctoring provider, {proctoring_provider}, is not a valid provider. "
+                         f"Please select from one of {available_providers}.")
+        self.proctoring_provider = proctoring_provider
+        self.available_providers = available_providers