Django Exceptions

    Django core exception classes are defined in .

    • exception AppRegistryNotReady[source]
    • This exception is raised when attempting to use models before the apploading process, which initializes the ORM, iscomplete.

    ObjectDoesNotExist

    • exception ObjectDoesNotExist[source]
    • The base class for DoesNotExist exceptions;a try/except for ObjectDoesNotExist will catch exceptions for all models.

    See get() for further informationon and DoesNotExist.

    EmptyResultSet

    • exception EmptyResultSet[source]
    • EmptyResultSet may be raised during query generation if a query won’treturn any results. Most Django projects won’t encounter this exception,but it might be useful for implementing custom lookups and expressions.

    FieldDoesNotExist

    • exception FieldDoesNotExist

    MultipleObjectsReturned

    • exception MultipleObjectsReturned[source]
    • The MultipleObjectsReturned exception is raised by a query if onlyone object is expected, but multiple objects are returned. A base versionof this exception is provided in ; each modelclass contains a subclassed version that can be used to identify thespecific object type that has returned multiple objects.

    See get() for further information.

    SuspiciousOperation

    • exception SuspiciousOperation[source]

    • The SuspiciousOperation exception is raised when a user hasperformed an operation that should be considered suspicious from a securityperspective, such as tampering with a session cookie. Subclasses ofSuspiciousOperation include:

      • DisallowedHost
      • DisallowedModelAdminLookup
      • DisallowedModelAdminToField
      • DisallowedRedirect
      • InvalidSessionKey
      • RequestDataTooBig
      • SuspiciousFileOperation
      • SuspiciousMultipartForm
      • TooManyFieldsSentIf a SuspiciousOperation exception reaches the WSGI handler level it islogged at the Error level and results ina . See the loggingdocumentation for more information.
    • exception PermissionDenied
    • The exception is raised when a user does not havepermission to perform the action requested.

    ViewDoesNotExist

    • exception ViewDoesNotExist
    • The exception is raised bydjango.urls when a requested view does not exist.

    MiddlewareNotUsed

    • exception MiddlewareNotUsed[source]
    • The MiddlewareNotUsed exception is raised when a middleware is notused in the server configuration.

    ImproperlyConfigured

    • exception ImproperlyConfigured[source]
    • The ImproperlyConfigured exception is raised when Django issomehow improperly configured – for example, if a value in settings.pyis incorrect or unparseable.

    FieldError

    • exception FieldError[source]

    • The FieldError exception is raised when there is a problem with amodel field. This can happen for several reasons:

      • A field in a model clashes with a field of the same name from anabstract base class
      • An infinite loop is caused by ordering
      • A keyword cannot be parsed from the filter parameters
      • A field cannot be determined from a keyword in the queryparameters
      • A join is not permitted on the specified field
      • A field name is invalid
      • A query contains invalid order_by arguments

    ValidationError

    NON_FIELD_ERRORS

    • NON_FIELD_ERRORS
    • exception RequestAborted[source]
    • New in Django 3.0:

    It is internal to the HTTP handler modules and you are unlikely to seeit elsewhere. If you are modifying HTTP handling code, you should raisethis when you encounter an aborted request to make sure the socket isclosed cleanly.

    SynchronousOnlyOperation

    • exception SynchronousOnlyOperation
    • New in Django 3.0:

    The exception is raised when code thatis only allowed in synchronous Python code is called from an asynchronouscontext (a thread with a running asynchronous event loop). These parts ofDjango are generally heavily reliant on thread-safety to function and don’twork correctly under coroutines sharing the same thread.

    If you are trying to call code that is synchronous-only from anasynchronous 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

    URL Resolver exceptions are defined in django.urls.

    Resolver404

    • exception Resolver404
    • The exception is raised by if the path passed to resolve() doesn’tmap to a view. It’s a subclass of .

    NoReverseMatch

    • exception NoReverseMatch
    • The NoReverseMatch exception is raised by when amatching URL in your URLconf cannot be identified based on the parameterssupplied.

    Database exceptions may be imported from django.db.

    • exception Error
    • exception InterfaceError
    • exception DatabaseError
    • exception DataError
    • exception OperationalError
    • exception IntegrityError
    • exception InternalError
    • exception ProgrammingError
    • exception NotSupportedError
    • The Django wrappers for database exceptions behave exactly the same asthe underlying database exceptions. See , the Python Database APISpecification v2.0, for further information.

    As per PEP 3134, a cause attribute is set with the original(underlying) database exception, allowing access to any additionalinformation provided.

    Http Exceptions

    Http exceptions may be imported from django.http.

    UnreadablePostError

    Transaction exceptions are defined in django.db.transaction.

    TransactionManagementError

    • exception TransactionManagementError
    • is raised for any and all problemsrelated to database transactions.

    Testing Framework Exceptions

    Exceptions provided by the django.test package.

    • exception client.
    • RedirectCycleError is raised when the test client detects aloop or an overly long chain of redirects.

    Django raises built-in Python exceptions when appropriate as well. See thePython documentation for further information on the .