Django の例外Link to this heading#

This exception is raised when attempting to use models before the app loading process, which initializes the ORM, is complete.

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.

The 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.

PermissionDenied 例外は、ユーザーにリクエストされたアクションを実行する権限がない場合に発生します。

ViewDoesNotExist 例外は、リクエストされたビューが存在しないい場合に、django.urls によって発生します。

MiddlewareNotUsed 例外は、サーバーの設定の中でミドルウェアが使用されなかった時に発生します。

ImproperlyConfigured 例外は、Django が何らかの点で不適切に設定されている場合に発生します。たとえば、settings.py に含まれる値が不正であったり、パースできないような場合が考えられます。

FieldError 例外は、モデルのフィールドに問題がある時に発生します。発生理由としては、次のようないくつかの理由が考えられます。

• A field in a model clashes with a field of the same name from an abstract 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 query parameters

• A join is not permitted on the specified field

• A field name is invalid

• A query contains invalid order_by arguments

ValidationError 例外は、データがフォームまたはモデルのフィールド検証に失敗すると発生します。検証 (validation) のより詳しい情報については、Form and Field Validation や Model Field Validation、Validator Reference を参照してください。

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().

The Resolver404 exception is raised by resolve() if the path passed to resolve() doesn't map to a view. It's a subclass of django.http.Http404.

The NoReverseMatch exception is raised by django.urls when a matching URL in your URLconf cannot be identified based on the parameters supplied.

UnreadablePostError は、ユーザーがアップロードをキャンセルすると発生します。

TransactionManagementError が発生するのは、データベースのトランザクションに関するあらゆる問題に対してです。

RedirectCycleError は、テストクライアントがループまたは過度に長いリダイレクトチェーンを検出した時に発生します。