Django raises some of its own exceptions as well as standard Python exceptions.
Django core exception classes are defined in django.core.exceptions.
The base class for Model.DoesNotExist exceptions. A try/except for ObjectDoesNotExist will catch DoesNotExist exceptions for all models.
See get().
EmptyResultSet may be raised during query generation if a query won’t return any results. Most Django projects won’t encounter this exception, but it might be useful for implementing custom lookups and expressions.
FieldDoesNotExist exception is raised by a model’s _meta.get_field() method when the requested field does not exist on the model or on the model’s parents.
The base class for Model.MultipleObjectsReturned exceptions. A try/except for MultipleObjectsReturned will catch MultipleObjectsReturned exceptions for all models.
See get().
The SuspiciousOperation exception is raised when a user has performed an operation that should be considered suspicious from a security perspective, such as tampering with a session cookie. Subclasses of SuspiciousOperation include:
DisallowedHost
DisallowedModelAdminLookup
DisallowedModelAdminToField
DisallowedRedirect
InvalidSessionKey
RequestDataTooBig
SuspiciousFileOperation
SuspiciousMultipartForm
SuspiciousSession
TooManyFieldsSent
If a SuspiciousOperation exception reaches the ASGI/WSGI handler level it is logged at the Error level and results in a HttpResponseBadRequest. See the logging documentation for more information.
settings.py is incorrect or unparseable.
ValidationErrors that don’t belong to a particular field in a form or model are classified as NON_FIELD_ERRORS. This constant is used as a key in dictionaries that otherwise map fields to their respective list of errors.
The RequestAborted exception is raised when a HTTP body being read in by the handler is cut off midstream and the client connection closes, or when the client does not send data and hits a timeout where the server closes the connection.
It is internal to the HTTP handler modules and you are unlikely to see it elsewhere. If you are modifying HTTP handling code, you should raise this when you encounter an aborted request to make sure the socket is closed cleanly.
The SynchronousOnlyOperation exception is raised when code that is only allowed in synchronous Python code is called from an asynchronous context (a thread with a running asynchronous event loop). These parts of Django are generally heavily reliant on thread-safety to function and don’t work correctly under coroutines sharing the same thread.
If you are trying to call code that is synchronous-only from an asynchronous thread, then create a synchronous thread and call it in that. You can accomplish this is with asgiref.sync.sync_to_async().
URL Resolver exceptions are defined in django.urls.
resolve() doesn’t map to a view. It’s a subclass of django.http.Http404.
Database exceptions may be imported from django.db.
Django wraps the standard database exceptions so that your Django code has a guaranteed common implementation of these classes.
The Django wrappers for database exceptions behave exactly the same as the underlying database exceptions. See PEP 249, the Python Database API Specification v2.0, for further information.
As per PEP 3134, a __cause__ attribute is set with the original (underlying) database exception, allowing access to any additional information provided.
Raised to prevent deletion of referenced objects when using django.db.models.PROTECT. models.ProtectedError is a subclass of IntegrityError.
Raised to prevent deletion of referenced objects when using django.db.models.RESTRICT. models.RestrictedError is a subclass of IntegrityError.
Http exceptions may be imported from django.http.
Transaction exceptions are defined in django.db.transaction.
Exceptions provided by the django.test package.
Django raises built-in Python exceptions when appropriate as well. See the Python documentation for further information on the Built-in Exceptions.