checks.txt 43 KB

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  1. ======================
  2. System check framework
  3. ======================
  4. .. currentmodule:: django.core.checks
  5. The system check framework is a set of static checks for validating Django
  6. projects. It detects common problems and provides hints for how to fix them.
  7. The framework is extensible so you can easily add your own checks.
  8. For details on how to add your own checks and integrate them with Django's
  9. system checks, see the :doc:`System check topic guide </topics/checks>`.
  10. API reference
  11. =============
  12. ``CheckMessage``
  13. ----------------
  14. .. class:: CheckMessage(level, msg, hint=None, obj=None, id=None)
  15. The warnings and errors raised by system checks must be instances of
  16. ``CheckMessage``. An instance encapsulates a single reportable error or
  17. warning. It also provides context and hints applicable to the message, and a
  18. unique identifier that is used for filtering purposes.
  19. Constructor arguments are:
  20. ``level``
  21. The severity of the message. Use one of the predefined values: ``DEBUG``,
  22. ``INFO``, ``WARNING``, ``ERROR``, ``CRITICAL``. If the level is greater or
  23. equal to ``ERROR``, then Django will prevent management commands from
  24. executing. Messages with level lower than ``ERROR`` (i.e. warnings) are
  25. reported to the console, but can be silenced.
  26. ``msg``
  27. A short (less than 80 characters) string describing the problem. The string
  28. should *not* contain newlines.
  29. ``hint``
  30. A single-line string providing a hint for fixing the problem. If no hint
  31. can be provided, or the hint is self-evident from the error message, the
  32. hint can be omitted, or a value of ``None`` can be used.
  33. ``obj``
  34. Optional. An object providing context for the message (for example, the
  35. model where the problem was discovered). The object should be a model,
  36. field, or manager or any other object that defines a ``__str__()`` method.
  37. The method is used while reporting all messages and its result precedes the
  38. message.
  39. ``id``
  40. Optional string. A unique identifier for the issue. Identifiers should
  41. follow the pattern ``applabel.X001``, where ``X`` is one of the letters
  42. ``CEWID``, indicating the message severity (``C`` for criticals, ``E`` for
  43. errors and so). The number can be allocated by the application, but should
  44. be unique within that application.
  45. There are subclasses to make creating messages with common levels easier. When
  46. using them you can omit the ``level`` argument because it is implied by the
  47. class name.
  48. .. class:: Debug(msg, hint=None, obj=None, id=None)
  49. .. class:: Info(msg, hint=None, obj=None, id=None)
  50. .. class:: Warning(msg, hint=None obj=None, id=None)
  51. .. class:: Error(msg, hint=None, obj=None, id=None)
  52. .. class:: Critical(msg, hint=None, obj=None, id=None)
  53. .. _system-check-builtin-tags:
  54. Builtin tags
  55. ============
  56. Django's system checks are organized using the following tags:
  57. * ``admin``: Checks of any admin site declarations.
  58. * ``async_support``: Checks asynchronous-related configuration.
  59. * ``caches``: Checks cache related configuration.
  60. * ``compatibility``: Flags potential problems with version upgrades.
  61. * ``database``: Checks database-related configuration issues. Database checks
  62. are not run by default because they do more than static code analysis as
  63. regular checks do. They are only run by the :djadmin:`migrate` command or if
  64. you specify configured database aliases using the ``--database`` option when
  65. calling the :djadmin:`check` command.
  66. * ``files``: Checks files related configuration.
  67. * ``models``: Checks of model, field, and manager definitions.
  68. * ``security``: Checks security related configuration.
  69. * ``signals``: Checks on signal declarations and handler registrations.
  70. * ``sites``: Checks :mod:`django.contrib.sites` configuration.
  71. * ``staticfiles``: Checks :mod:`django.contrib.staticfiles` configuration.
  72. * ``templates``: Checks template related configuration.
  73. * ``translation``: Checks translation related configuration.
  74. * ``urls``: Checks URL configuration.
  75. Some checks may be registered with multiple tags.
  76. .. versionchanged:: 3.2
  77. The ``sites`` tag was added.
  78. .. versionchanged:: 4.0
  79. The ``files`` tag was added.
  80. Core system checks
  81. ==================
  82. Asynchronous support
  83. --------------------
  84. The following checks verify your setup for :doc:`/topics/async`:
  85. * **async.E001**: You should not set the :envvar:`DJANGO_ALLOW_ASYNC_UNSAFE`
  86. environment variable in deployment. This disables :ref:`async safety
  87. protection <async-safety>`.
  88. Backwards compatibility
  89. -----------------------
  90. Compatibility checks warn of potential problems that might occur after
  91. upgrading Django.
  92. * **2_0.W001**: Your URL pattern ``<pattern>`` has a ``route`` that contains
  93. ``(?P<``, begins with a ``^``, or ends with a ``$``. This was likely an
  94. oversight when migrating from ``url()`` to :func:`~django.urls.path`.
  95. * **4_0.E001**: As of Django 4.0, the values in the
  96. :setting:`CSRF_TRUSTED_ORIGINS` setting must start with a scheme (usually
  97. ``http://`` or ``https://``) but found ``<hostname>``.
  98. Caches
  99. ------
  100. The following checks verify that your :setting:`CACHES` setting is correctly
  101. configured:
  102. * **caches.E001**: You must define a ``'default'`` cache in your
  103. :setting:`CACHES` setting.
  104. * **caches.W002**: Your ``<cache>`` configuration might expose your cache or
  105. lead to corruption of your data because its
  106. :setting:`LOCATION <CACHES-LOCATION>` matches/is inside/contains
  107. :setting:`MEDIA_ROOT`/:setting:`STATIC_ROOT`/:setting:`STATICFILES_DIRS`.
  108. * **caches.W003**: Your ``<cache>`` cache :setting:`LOCATION <CACHES-LOCATION>`
  109. is relative. Use an absolute path instead.
  110. Database
  111. --------
  112. MySQL and MariaDB
  113. ~~~~~~~~~~~~~~~~~
  114. If you're using MySQL or MariaDB, the following checks will be performed:
  115. * **mysql.E001**: MySQL/MariaDB does not allow unique ``CharField``\s to have a
  116. ``max_length`` > 255. *This check was changed to* ``mysql.W003`` *in Django
  117. 3.1 as the real maximum size depends on many factors.*
  118. * **mysql.W002**: MySQL/MariaDB Strict Mode is not set for database connection
  119. ``<alias>``. See also :ref:`mysql-sql-mode`.
  120. * **mysql.W003**: MySQL/MariaDB may not allow unique ``CharField``\s to have a
  121. ``max_length`` > 255.
  122. Managing files
  123. --------------
  124. .. versionadded:: 4.0
  125. The following checks verify your setup for :doc:`/topics/files`:
  126. * **files.E001**: The :setting:`FILE_UPLOAD_TEMP_DIR` setting refers to the
  127. nonexistent directory ``<path>``.
  128. Model fields
  129. ------------
  130. * **fields.E001**: Field names must not end with an underscore.
  131. * **fields.E002**: Field names must not contain ``"__"``.
  132. * **fields.E003**: ``pk`` is a reserved word that cannot be used as a field
  133. name.
  134. * **fields.E004**: ``choices`` must be an iterable (e.g., a list or tuple).
  135. * **fields.E005**: ``choices`` must be an iterable returning ``(actual value,
  136. human readable name)`` tuples.
  137. * **fields.E006**: ``db_index`` must be ``None``, ``True`` or ``False``.
  138. * **fields.E007**: Primary keys must not have ``null=True``.
  139. * **fields.E008**: All ``validators`` must be callable.
  140. * **fields.E009**: ``max_length`` is too small to fit the longest value in
  141. ``choices`` (``<count>`` characters).
  142. * **fields.E010**: ``<field>`` default should be a callable instead of an
  143. instance so that it's not shared between all field instances.
  144. * **fields.E100**: ``AutoField``\s must set primary_key=True.
  145. * **fields.E110**: ``BooleanField``\s do not accept null values. *This check
  146. appeared before support for null values was added in Django 2.1.*
  147. * **fields.E120**: ``CharField``\s must define a ``max_length`` attribute.
  148. * **fields.E121**: ``max_length`` must be a positive integer.
  149. * **fields.W122**: ``max_length`` is ignored when used with
  150. ``<integer field type>``.
  151. * **fields.E130**: ``DecimalField``\s must define a ``decimal_places`` attribute.
  152. * **fields.E131**: ``decimal_places`` must be a non-negative integer.
  153. * **fields.E132**: ``DecimalField``\s must define a ``max_digits`` attribute.
  154. * **fields.E133**: ``max_digits`` must be a non-negative integer.
  155. * **fields.E134**: ``max_digits`` must be greater or equal to ``decimal_places``.
  156. * **fields.E140**: ``FilePathField``\s must have either ``allow_files`` or
  157. ``allow_folders`` set to True.
  158. * **fields.E150**: ``GenericIPAddressField``\s cannot accept blank values if
  159. null values are not allowed, as blank values are stored as nulls.
  160. * **fields.E160**: The options ``auto_now``, ``auto_now_add``, and ``default``
  161. are mutually exclusive. Only one of these options may be present.
  162. * **fields.W161**: Fixed default value provided.
  163. * **fields.W162**: ``<database>`` does not support a database index on
  164. ``<field data type>`` columns.
  165. * **fields.E170**: ``BinaryField``’s ``default`` cannot be a string. Use bytes
  166. content instead.
  167. * **fields.E180**: ``<database>`` does not support ``JSONField``\s.
  168. * **fields.E190**: ``<database>`` does not support a database collation on
  169. ``<field_type>``\s.
  170. * **fields.E900**: ``IPAddressField`` has been removed except for support in
  171. historical migrations.
  172. * **fields.W900**: ``IPAddressField`` has been deprecated. Support for it
  173. (except in historical migrations) will be removed in Django 1.9. *This check
  174. appeared in Django 1.7 and 1.8*.
  175. * **fields.W901**: ``CommaSeparatedIntegerField`` has been deprecated. Support
  176. for it (except in historical migrations) will be removed in Django 2.0. *This
  177. check appeared in Django 1.10 and 1.11*.
  178. * **fields.E901**: ``CommaSeparatedIntegerField`` is removed except for support
  179. in historical migrations.
  180. * **fields.W902**: ``FloatRangeField`` is deprecated and will be removed in
  181. Django 3.1. *This check appeared in Django 2.2 and 3.0*.
  182. * **fields.W903**: ``NullBooleanField`` is deprecated. Support for it (except
  183. in historical migrations) will be removed in Django 4.0. *This check appeared
  184. in Django 3.1 and 3.2*.
  185. * **fields.E903**: ``NullBooleanField`` is removed except for support in
  186. historical migrations.
  187. * **fields.W904**: ``django.contrib.postgres.fields.JSONField`` is deprecated.
  188. Support for it (except in historical migrations) will be removed in Django
  189. 4.0. *This check appeared in Django 3.1 and 3.2*.
  190. * **fields.E904**: ``django.contrib.postgres.fields.JSONField`` is removed
  191. except for support in historical migrations.
  192. File fields
  193. ~~~~~~~~~~~
  194. * **fields.E200**: ``unique`` is not a valid argument for a ``FileField``.
  195. *This check is removed in Django 1.11*.
  196. * **fields.E201**: ``primary_key`` is not a valid argument for a ``FileField``.
  197. * **fields.E202**: ``FileField``’s ``upload_to`` argument must be a relative
  198. path, not an absolute path.
  199. * **fields.E210**: Cannot use ``ImageField`` because Pillow is not installed.
  200. Related fields
  201. ~~~~~~~~~~~~~~
  202. * **fields.E300**: Field defines a relation with model ``<model>``, which is
  203. either not installed, or is abstract.
  204. * **fields.E301**: Field defines a relation with the model
  205. ``<app_label>.<model>`` which has been swapped out.
  206. * **fields.E302**: Accessor for field ``<app_label>.<model>.<field name>``
  207. clashes with field ``<app_label>.<model>.<field name>``.
  208. * **fields.E303**: Reverse query name for field
  209. ``<app_label>.<model>.<field name>`` clashes with field
  210. ``<app_label>.<model>.<field name>``.
  211. * **fields.E304**: Field name ``<app_label>.<model>.<field name>`` clashes with
  212. accessor for ``<app_label>.<model>.<field name>``.
  213. * **fields.E305**: Field name ``<app_label>.<model>.<field name>`` clashes with
  214. reverse query name for ``<app_label>.<model>.<field name>``.
  215. * **fields.E306**: Related name must be a valid Python identifier or end with
  216. a ``'+'``.
  217. * **fields.E307**: The field ``<app label>.<model>.<field name>`` was declared
  218. with a lazy reference to ``<app label>.<model>``, but app ``<app label>``
  219. isn't installed or doesn't provide model ``<model>``.
  220. * **fields.E308**: Reverse query name ``<related query name>`` must not end
  221. with an underscore.
  222. * **fields.E309**: Reverse query name ``<related query name>`` must not contain
  223. ``'__'``.
  224. * **fields.E310**: No subset of the fields ``<field1>``, ``<field2>``, ... on
  225. model ``<model>`` is unique.
  226. * **fields.E311**: ``<model>.<field name>`` must be unique because it is
  227. referenced by a ``ForeignKey``.
  228. * **fields.E312**: The ``to_field`` ``<field name>`` doesn't exist on the
  229. related model ``<app label>.<model>``.
  230. * **fields.E320**: Field specifies ``on_delete=SET_NULL``, but cannot be null.
  231. * **fields.E321**: The field specifies ``on_delete=SET_DEFAULT``, but has no
  232. default value.
  233. * **fields.E330**: ``ManyToManyField``\s cannot be unique.
  234. * **fields.E331**: Field specifies a many-to-many relation through model
  235. ``<model>``, which has not been installed.
  236. * **fields.E332**: Many-to-many fields with intermediate tables must not be
  237. symmetrical. *This check appeared before Django 3.0.*
  238. * **fields.E333**: The model is used as an intermediate model by ``<model>``,
  239. but it has more than two foreign keys to ``<model>``, which is ambiguous.
  240. You must specify which two foreign keys Django should use via the
  241. ``through_fields`` keyword argument.
  242. * **fields.E334**: The model is used as an intermediate model by ``<model>``,
  243. but it has more than one foreign key from ``<model>``, which is ambiguous.
  244. You must specify which foreign key Django should use via the
  245. ``through_fields`` keyword argument.
  246. * **fields.E335**: The model is used as an intermediate model by ``<model>``,
  247. but it has more than one foreign key to ``<model>``, which is ambiguous.
  248. You must specify which foreign key Django should use via the
  249. ``through_fields`` keyword argument.
  250. * **fields.E336**: The model is used as an intermediary model by ``<model>``,
  251. but it does not have foreign key to ``<model>`` or ``<model>``.
  252. * **fields.E337**: Field specifies ``through_fields`` but does not provide the
  253. names of the two link fields that should be used for the relation through
  254. ``<model>``.
  255. * **fields.E338**: The intermediary model ``<through model>`` has no field
  256. ``<field name>``.
  257. * **fields.E339**: ``<model>.<field name>`` is not a foreign key to ``<model>``.
  258. * **fields.E340**: The field's intermediary table ``<table name>`` clashes with
  259. the table name of ``<model>``/``<model>.<field name>``.
  260. * **fields.W340**: ``null`` has no effect on ``ManyToManyField``.
  261. * **fields.W341**: ``ManyToManyField`` does not support ``validators``.
  262. * **fields.W342**: Setting ``unique=True`` on a ``ForeignKey`` has the same
  263. effect as using a ``OneToOneField``.
  264. * **fields.W343**: ``limit_choices_to`` has no effect on ``ManyToManyField``
  265. with a ``through`` model. *This check appeared before Django 4.0.*
  266. * **fields.W344**: The field's intermediary table ``<table name>`` clashes with
  267. the table name of ``<model>``/``<model>.<field name>``.
  268. * **fields.W345**: ``related_name`` has no effect on ``ManyToManyField`` with a
  269. symmetrical relationship, e.g. to "self".
  270. Models
  271. ------
  272. * **models.E001**: ``<swappable>`` is not of the form ``app_label.app_name``.
  273. * **models.E002**: ``<SETTING>`` references ``<model>``, which has not been
  274. installed, or is abstract.
  275. * **models.E003**: The model has two identical many-to-many relations through
  276. the intermediate model ``<app_label>.<model>``.
  277. * **models.E004**: ``id`` can only be used as a field name if the field also
  278. sets ``primary_key=True``.
  279. * **models.E005**: The field ``<field name>`` from parent model ``<model>``
  280. clashes with the field ``<field name>`` from parent model ``<model>``.
  281. * **models.E006**: The field clashes with the field ``<field name>`` from model
  282. ``<model>``.
  283. * **models.E007**: Field ``<field name>`` has column name ``<column name>``
  284. that is used by another field.
  285. * **models.E008**: ``index_together`` must be a list or tuple.
  286. * **models.E009**: All ``index_together`` elements must be lists or tuples.
  287. * **models.E010**: ``unique_together`` must be a list or tuple.
  288. * **models.E011**: All ``unique_together`` elements must be lists or tuples.
  289. * **models.E012**: ``constraints/indexes/index_together/unique_together``
  290. refers to the nonexistent field ``<field name>``.
  291. * **models.E013**: ``constraints/indexes/index_together/unique_together``
  292. refers to a ``ManyToManyField`` ``<field name>``, but ``ManyToManyField``\s
  293. are not supported for that option.
  294. * **models.E014**: ``ordering`` must be a tuple or list (even if you want to
  295. order by only one field).
  296. * **models.E015**: ``ordering`` refers to the nonexistent field, related field,
  297. or lookup ``<field name>``.
  298. * **models.E016**: ``constraints/indexes/index_together/unique_together``
  299. refers to field ``<field_name>`` which is not local to model ``<model>``.
  300. * **models.E017**: Proxy model ``<model>`` contains model fields.
  301. * **models.E018**: Autogenerated column name too long for field ``<field>``.
  302. Maximum length is ``<maximum length>`` for database ``<alias>``.
  303. * **models.E019**: Autogenerated column name too long for M2M field
  304. ``<M2M field>``. Maximum length is ``<maximum length>`` for database
  305. ``<alias>``.
  306. * **models.E020**: The ``<model>.check()`` class method is currently overridden.
  307. * **models.E021**: ``ordering`` and ``order_with_respect_to`` cannot be used
  308. together.
  309. * **models.E022**: ``<function>`` contains a lazy reference to
  310. ``<app label>.<model>``, but app ``<app label>`` isn't installed or
  311. doesn't provide model ``<model>``.
  312. * **models.E023**: The model name ``<model>`` cannot start or end with an
  313. underscore as it collides with the query lookup syntax.
  314. * **models.E024**: The model name ``<model>`` cannot contain double underscores
  315. as it collides with the query lookup syntax.
  316. * **models.E025**: The property ``<property name>`` clashes with a related
  317. field accessor.
  318. * **models.E026**: The model cannot have more than one field with
  319. ``primary_key=True``.
  320. * **models.W027**: ``<database>`` does not support check constraints.
  321. * **models.E028**: ``db_table`` ``<db_table>`` is used by multiple models:
  322. ``<model list>``.
  323. * **models.E029**: index name ``<index>`` is not unique for model ``<model>``.
  324. * **models.E030**: index name ``<index>`` is not unique among models:
  325. ``<model list>``.
  326. * **models.E031**: constraint name ``<constraint>`` is not unique for model
  327. ``<model>``.
  328. * **models.E032**: constraint name ``<constraint>`` is not unique among
  329. models: ``<model list>``.
  330. * **models.E033**: The index name ``<index>`` cannot start with an underscore
  331. or a number.
  332. * **models.E034**: The index name ``<index>`` cannot be longer than
  333. ``<max_length>`` characters.
  334. * **models.W035**: ``db_table`` ``<db_table>`` is used by multiple models:
  335. ``<model list>``.
  336. * **models.W036**: ``<database>`` does not support unique constraints with
  337. conditions.
  338. * **models.W037**: ``<database>`` does not support indexes with conditions.
  339. * **models.W038**: ``<database>`` does not support deferrable unique
  340. constraints.
  341. * **models.W039**: ``<database>`` does not support unique constraints with
  342. non-key columns.
  343. * **models.W040**: ``<database>`` does not support indexes with non-key
  344. columns.
  345. * **models.E041**: ``constraints`` refers to the joined field ``<field name>``.
  346. * **models.W042**: Auto-created primary key used when not defining a primary
  347. key type, by default ``django.db.models.AutoField``.
  348. * **models.W043**: ``<database>`` does not support indexes on expressions.
  349. * **models.W044**: ``<database>`` does not support unique constraints on
  350. expressions.
  351. Security
  352. --------
  353. The security checks do not make your site secure. They do not audit code, do
  354. intrusion detection, or do anything particularly complex. Rather, they help
  355. perform an automated, low-hanging-fruit checklist, that can help you to improve
  356. your site's security.
  357. Some of these checks may not be appropriate for your particular deployment
  358. configuration. For instance, if you do your HTTP to HTTPS redirection in a load
  359. balancer, it'd be irritating to be constantly warned about not having enabled
  360. :setting:`SECURE_SSL_REDIRECT`. Use :setting:`SILENCED_SYSTEM_CHECKS` to
  361. silence unneeded checks.
  362. The following checks are run if you use the :option:`check --deploy` option:
  363. * **security.W001**: You do not have
  364. :class:`django.middleware.security.SecurityMiddleware` in your
  365. :setting:`MIDDLEWARE` so the :setting:`SECURE_HSTS_SECONDS`,
  366. :setting:`SECURE_CONTENT_TYPE_NOSNIFF`, :setting:`SECURE_REFERRER_POLICY`,
  367. :setting:`SECURE_CROSS_ORIGIN_OPENER_POLICY`, and
  368. :setting:`SECURE_SSL_REDIRECT` settings will have no effect.
  369. * **security.W002**: You do not have
  370. :class:`django.middleware.clickjacking.XFrameOptionsMiddleware` in your
  371. :setting:`MIDDLEWARE`, so your pages will not be served with an
  372. ``'x-frame-options'`` header. Unless there is a good reason for your
  373. site to be served in a frame, you should consider enabling this
  374. header to help prevent clickjacking attacks.
  375. * **security.W003**: You don't appear to be using Django's built-in cross-site
  376. request forgery protection via the middleware
  377. (:class:`django.middleware.csrf.CsrfViewMiddleware` is not in your
  378. :setting:`MIDDLEWARE`). Enabling the middleware is the safest
  379. approach to ensure you don't leave any holes.
  380. * **security.W004**: You have not set a value for the
  381. :setting:`SECURE_HSTS_SECONDS` setting. If your entire site is served only
  382. over SSL, you may want to consider setting a value and enabling :ref:`HTTP
  383. Strict Transport Security <http-strict-transport-security>`. Be sure to read
  384. the documentation first; enabling HSTS carelessly can cause serious,
  385. irreversible problems.
  386. * **security.W005**: You have not set the
  387. :setting:`SECURE_HSTS_INCLUDE_SUBDOMAINS` setting to ``True``. Without this,
  388. your site is potentially vulnerable to attack via an insecure connection to a
  389. subdomain. Only set this to ``True`` if you are certain that all subdomains of
  390. your domain should be served exclusively via SSL.
  391. * **security.W006**: Your :setting:`SECURE_CONTENT_TYPE_NOSNIFF` setting is not
  392. set to ``True``, so your pages will not be served with an
  393. ``'X-Content-Type-Options: nosniff'`` header. You should consider enabling
  394. this header to prevent the browser from identifying content types incorrectly.
  395. * **security.W007**: Your ``SECURE_BROWSER_XSS_FILTER`` setting is not
  396. set to ``True``, so your pages will not be served with an
  397. ``'X-XSS-Protection: 1; mode=block'`` header. You should consider enabling
  398. this header to activate the browser's XSS filtering and help prevent XSS
  399. attacks. *This check is removed in Django 3.0 as the* ``X-XSS-Protection``
  400. *header is no longer honored by modern browsers.*
  401. * **security.W008**: Your :setting:`SECURE_SSL_REDIRECT` setting is not set to
  402. ``True``. Unless your site should be available over both SSL and non-SSL
  403. connections, you may want to either set this setting to ``True`` or configure
  404. a load balancer or reverse-proxy server to redirect all connections to HTTPS.
  405. * **security.W009**: Your :setting:`SECRET_KEY` has less than 50 characters,
  406. less than 5 unique characters, or it's prefixed with ``'django-insecure-'``
  407. indicating that it was generated automatically by Django. Please generate a
  408. long and random ``SECRET_KEY``, otherwise many of Django's security-critical
  409. features will be vulnerable to attack.
  410. * **security.W010**: You have :mod:`django.contrib.sessions` in your
  411. :setting:`INSTALLED_APPS` but you have not set
  412. :setting:`SESSION_COOKIE_SECURE` to ``True``. Using a secure-only session
  413. cookie makes it more difficult for network traffic sniffers to hijack user
  414. sessions.
  415. * **security.W011**: You have
  416. :class:`django.contrib.sessions.middleware.SessionMiddleware` in your
  417. :setting:`MIDDLEWARE`, but you have not set :setting:`SESSION_COOKIE_SECURE`
  418. to ``True``. Using a secure-only session cookie makes it more difficult for
  419. network traffic sniffers to hijack user sessions.
  420. * **security.W012**: :setting:`SESSION_COOKIE_SECURE` is not set to ``True``.
  421. Using a secure-only session cookie makes it more difficult for network traffic
  422. sniffers to hijack user sessions.
  423. * **security.W013**: You have :mod:`django.contrib.sessions` in your
  424. :setting:`INSTALLED_APPS`, but you have not set
  425. :setting:`SESSION_COOKIE_HTTPONLY` to ``True``. Using an ``HttpOnly`` session
  426. cookie makes it more difficult for cross-site scripting attacks to hijack user
  427. sessions.
  428. * **security.W014**: You have
  429. :class:`django.contrib.sessions.middleware.SessionMiddleware` in your
  430. :setting:`MIDDLEWARE`, but you have not set :setting:`SESSION_COOKIE_HTTPONLY`
  431. to ``True``. Using an ``HttpOnly`` session cookie makes it more difficult for
  432. cross-site scripting attacks to hijack user sessions.
  433. * **security.W015**: :setting:`SESSION_COOKIE_HTTPONLY` is not set to ``True``.
  434. Using an ``HttpOnly`` session cookie makes it more difficult for cross-site
  435. scripting attacks to hijack user sessions.
  436. * **security.W016**: :setting:`CSRF_COOKIE_SECURE` is not set to ``True``.
  437. Using a secure-only CSRF cookie makes it more difficult for network traffic
  438. sniffers to steal the CSRF token.
  439. * **security.W017**: :setting:`CSRF_COOKIE_HTTPONLY` is not set to ``True``.
  440. Using an ``HttpOnly`` CSRF cookie makes it more difficult for cross-site
  441. scripting attacks to steal the CSRF token. *This check is removed in Django
  442. 1.11 as the* :setting:`CSRF_COOKIE_HTTPONLY` *setting offers no practical
  443. benefit.*
  444. * **security.W018**: You should not have :setting:`DEBUG` set to ``True`` in
  445. deployment.
  446. * **security.W019**: You have
  447. :class:`django.middleware.clickjacking.XFrameOptionsMiddleware` in your
  448. :setting:`MIDDLEWARE`, but :setting:`X_FRAME_OPTIONS` is not set to
  449. ``'DENY'``. Unless there is a good reason for your site to serve other parts
  450. of itself in a frame, you should change it to ``'DENY'``.
  451. * **security.W020**: :setting:`ALLOWED_HOSTS` must not be empty in deployment.
  452. * **security.W021**: You have not set the
  453. :setting:`SECURE_HSTS_PRELOAD` setting to ``True``. Without this, your site
  454. cannot be submitted to the browser preload list.
  455. * **security.W022**: You have not set the :setting:`SECURE_REFERRER_POLICY`
  456. setting. Without this, your site will not send a Referrer-Policy header. You
  457. should consider enabling this header to protect user privacy.
  458. * **security.E023**: You have set the :setting:`SECURE_REFERRER_POLICY` setting
  459. to an invalid value.
  460. * **security.E024**: You have set the
  461. :setting:`SECURE_CROSS_ORIGIN_OPENER_POLICY` setting to an invalid value.
  462. The following checks verify that your security-related settings are correctly
  463. configured:
  464. * **security.E100**: ``DEFAULT_HASHING_ALGORITHM`` must be ``'sha1'`` or
  465. ``'sha256'``. *This check appeared in Django 3.1 and 3.2*.
  466. * **security.E101**: The CSRF failure view ``'path.to.view'`` does not take the
  467. correct number of arguments.
  468. * **security.E102**: The CSRF failure view ``'path.to.view'`` could not be
  469. imported.
  470. Signals
  471. -------
  472. * **signals.E001**: ``<handler>`` was connected to the ``<signal>`` signal with
  473. a lazy reference to the sender ``<app label>.<model>``, but app ``<app label>``
  474. isn't installed or doesn't provide model ``<model>``.
  475. Templates
  476. ---------
  477. The following checks verify that your :setting:`TEMPLATES` setting is correctly
  478. configured:
  479. * **templates.E001**: You have ``'APP_DIRS': True`` in your
  480. :setting:`TEMPLATES` but also specify ``'loaders'`` in ``OPTIONS``. Either
  481. remove ``APP_DIRS`` or remove the ``'loaders'`` option.
  482. * **templates.E002**: ``string_if_invalid`` in :setting:`TEMPLATES`
  483. :setting:`OPTIONS <TEMPLATES-OPTIONS>` must be a string but got: ``{value}``
  484. (``{type}``).
  485. Translation
  486. -----------
  487. The following checks are performed on your translation configuration:
  488. * **translation.E001**: You have provided an invalid value for the
  489. :setting:`LANGUAGE_CODE` setting: ``<value>``.
  490. * **translation.E002**: You have provided an invalid language code in the
  491. :setting:`LANGUAGES` setting: ``<value>``.
  492. * **translation.E003**: You have provided an invalid language code in the
  493. :setting:`LANGUAGES_BIDI` setting: ``<value>``.
  494. * **translation.E004**: You have provided a value for the
  495. :setting:`LANGUAGE_CODE` setting that is not in the :setting:`LANGUAGES`
  496. setting.
  497. URLs
  498. ----
  499. The following checks are performed on your URL configuration:
  500. * **urls.W001**: Your URL pattern ``<pattern>`` uses
  501. :func:`~django.urls.include` with a ``route`` ending with a ``$``. Remove the
  502. dollar from the ``route`` to avoid problems including URLs.
  503. * **urls.W002**: Your URL pattern ``<pattern>`` has a ``route`` beginning with
  504. a ``/``. Remove this slash as it is unnecessary. If this pattern is targeted
  505. in an :func:`~django.urls.include`, ensure the :func:`~django.urls.include`
  506. pattern has a trailing ``/``.
  507. * **urls.W003**: Your URL pattern ``<pattern>`` has a ``name``
  508. including a ``:``. Remove the colon, to avoid ambiguous namespace
  509. references.
  510. * **urls.E004**: Your URL pattern ``<pattern>`` is invalid. Ensure that
  511. ``urlpatterns`` is a list of :func:`~django.urls.path` and/or
  512. :func:`~django.urls.re_path` instances.
  513. * **urls.W005**: URL namespace ``<namespace>`` isn't unique. You may not be
  514. able to reverse all URLs in this namespace.
  515. * **urls.E006**: The :setting:`MEDIA_URL`/ :setting:`STATIC_URL` setting must
  516. end with a slash.
  517. * **urls.E007**: The custom ``handlerXXX`` view ``'path.to.view'`` does not
  518. take the correct number of arguments (…).
  519. * **urls.E008**: The custom ``handlerXXX`` view ``'path.to.view'`` could not be
  520. imported.
  521. * **urls.E009**: Your URL pattern ``<pattern>`` has an invalid view, pass
  522. ``<view>.as_view()`` instead of ``<view>``.
  523. ``contrib`` app checks
  524. ======================
  525. ``admin``
  526. ---------
  527. Admin checks are all performed as part of the ``admin`` tag.
  528. The following checks are performed on any
  529. :class:`~django.contrib.admin.ModelAdmin` (or subclass) that is registered
  530. with the admin site:
  531. * **admin.E001**: The value of ``raw_id_fields`` must be a list or tuple.
  532. * **admin.E002**: The value of ``raw_id_fields[n]`` refers to ``<field name>``,
  533. which is not a field of ``<model>``.
  534. * **admin.E003**: The value of ``raw_id_fields[n]`` must be a foreign key or
  535. a many-to-many field.
  536. * **admin.E004**: The value of ``fields`` must be a list or tuple.
  537. * **admin.E005**: Both ``fieldsets`` and ``fields`` are specified.
  538. * **admin.E006**: The value of ``fields`` contains duplicate field(s).
  539. * **admin.E007**: The value of ``fieldsets`` must be a list or tuple.
  540. * **admin.E008**: The value of ``fieldsets[n]`` must be a list or tuple.
  541. * **admin.E009**: The value of ``fieldsets[n]`` must be of length 2.
  542. * **admin.E010**: The value of ``fieldsets[n][1]`` must be a dictionary.
  543. * **admin.E011**: The value of ``fieldsets[n][1]`` must contain the key
  544. ``fields``.
  545. * **admin.E012**: There are duplicate field(s) in ``fieldsets[n][1]``.
  546. * **admin.E013**: ``fields[n]/fieldsets[n][m]`` cannot include the
  547. ``ManyToManyField`` ``<field name>``, because that field manually specifies a
  548. relationship model.
  549. * **admin.E014**: The value of ``exclude`` must be a list or tuple.
  550. * **admin.E015**: The value of ``exclude`` contains duplicate field(s).
  551. * **admin.E016**: The value of ``form`` must inherit from ``BaseModelForm``.
  552. * **admin.E017**: The value of ``filter_vertical`` must be a list or tuple.
  553. * **admin.E018**: The value of ``filter_horizontal`` must be a list or tuple.
  554. * **admin.E019**: The value of ``filter_vertical[n]/filter_horizontal[n]``
  555. refers to ``<field name>``, which is not a field of ``<model>``.
  556. * **admin.E020**: The value of ``filter_vertical[n]/filter_horizontal[n]``
  557. must be a many-to-many field.
  558. * **admin.E021**: The value of ``radio_fields`` must be a dictionary.
  559. * **admin.E022**: The value of ``radio_fields`` refers to ``<field name>``,
  560. which is not a field of ``<model>``.
  561. * **admin.E023**: The value of ``radio_fields`` refers to ``<field name>``,
  562. which is not an instance of ``ForeignKey``, and does not have a ``choices``
  563. definition.
  564. * **admin.E024**: The value of ``radio_fields[<field name>]`` must be either
  565. ``admin.HORIZONTAL`` or ``admin.VERTICAL``.
  566. * **admin.E025**: The value of ``view_on_site`` must be either a callable or a
  567. boolean value.
  568. * **admin.E026**: The value of ``prepopulated_fields`` must be a dictionary.
  569. * **admin.E027**: The value of ``prepopulated_fields`` refers to
  570. ``<field name>``, which is not a field of ``<model>``.
  571. * **admin.E028**: The value of ``prepopulated_fields`` refers to
  572. ``<field name>``, which must not be a ``DateTimeField``, a ``ForeignKey``,
  573. a ``OneToOneField``, or a ``ManyToManyField`` field.
  574. * **admin.E029**: The value of ``prepopulated_fields[<field name>]`` must be a
  575. list or tuple.
  576. * **admin.E030**: The value of ``prepopulated_fields`` refers to
  577. ``<field name>``, which is not a field of ``<model>``.
  578. * **admin.E031**: The value of ``ordering`` must be a list or tuple.
  579. * **admin.E032**: The value of ``ordering`` has the random ordering marker
  580. ``?``, but contains other fields as well.
  581. * **admin.E033**: The value of ``ordering`` refers to ``<field name>``, which
  582. is not a field of ``<model>``.
  583. * **admin.E034**: The value of ``readonly_fields`` must be a list or tuple.
  584. * **admin.E035**: The value of ``readonly_fields[n]`` is not a callable, an
  585. attribute of ``<ModelAdmin class>``, or an attribute of ``<model>``.
  586. * **admin.E036**: The value of ``autocomplete_fields`` must be a list or tuple.
  587. * **admin.E037**: The value of ``autocomplete_fields[n]`` refers to
  588. ``<field name>``, which is not a field of ``<model>``.
  589. * **admin.E038**: The value of ``autocomplete_fields[n]`` must be a foreign
  590. key or a many-to-many field.
  591. * **admin.E039**: An admin for model ``<model>`` has to be registered to be
  592. referenced by ``<modeladmin>.autocomplete_fields``.
  593. * **admin.E040**: ``<modeladmin>`` must define ``search_fields``, because
  594. it's referenced by ``<other_modeladmin>.autocomplete_fields``.
  595. ``ModelAdmin``
  596. ~~~~~~~~~~~~~~
  597. The following checks are performed on any
  598. :class:`~django.contrib.admin.ModelAdmin` that is registered
  599. with the admin site:
  600. * **admin.E101**: The value of ``save_as`` must be a boolean.
  601. * **admin.E102**: The value of ``save_on_top`` must be a boolean.
  602. * **admin.E103**: The value of ``inlines`` must be a list or tuple.
  603. * **admin.E104**: ``<InlineModelAdmin class>`` must inherit from
  604. ``InlineModelAdmin``.
  605. * **admin.E105**: ``<InlineModelAdmin class>`` must have a ``model`` attribute.
  606. * **admin.E106**: The value of ``<InlineModelAdmin class>.model`` must be a
  607. ``Model``.
  608. * **admin.E107**: The value of ``list_display`` must be a list or tuple.
  609. * **admin.E108**: The value of ``list_display[n]`` refers to ``<label>``,
  610. which is not a callable, an attribute of ``<ModelAdmin class>``, or an
  611. attribute or method on ``<model>``.
  612. * **admin.E109**: The value of ``list_display[n]`` must not be a
  613. ``ManyToManyField`` field.
  614. * **admin.E110**: The value of ``list_display_links`` must be a list, a tuple,
  615. or ``None``.
  616. * **admin.E111**: The value of ``list_display_links[n]`` refers to ``<label>``,
  617. which is not defined in ``list_display``.
  618. * **admin.E112**: The value of ``list_filter`` must be a list or tuple.
  619. * **admin.E113**: The value of ``list_filter[n]`` must inherit from
  620. ``ListFilter``.
  621. * **admin.E114**: The value of ``list_filter[n]`` must not inherit from
  622. ``FieldListFilter``.
  623. * **admin.E115**: The value of ``list_filter[n][1]`` must inherit from
  624. ``FieldListFilter``.
  625. * **admin.E116**: The value of ``list_filter[n]`` refers to ``<label>``,
  626. which does not refer to a Field.
  627. * **admin.E117**: The value of ``list_select_related`` must be a boolean,
  628. tuple or list.
  629. * **admin.E118**: The value of ``list_per_page`` must be an integer.
  630. * **admin.E119**: The value of ``list_max_show_all`` must be an integer.
  631. * **admin.E120**: The value of ``list_editable`` must be a list or tuple.
  632. * **admin.E121**: The value of ``list_editable[n]`` refers to ``<label>``,
  633. which is not a field of ``<model>``.
  634. * **admin.E122**: The value of ``list_editable[n]`` refers to ``<label>``,
  635. which is not contained in ``list_display``.
  636. * **admin.E123**: The value of ``list_editable[n]`` cannot be in both
  637. ``list_editable`` and ``list_display_links``.
  638. * **admin.E124**: The value of ``list_editable[n]`` refers to the first field
  639. in ``list_display`` (``<label>``), which cannot be used unless
  640. ``list_display_links`` is set.
  641. * **admin.E125**: The value of ``list_editable[n]`` refers to ``<field name>``,
  642. which is not editable through the admin.
  643. * **admin.E126**: The value of ``search_fields`` must be a list or tuple.
  644. * **admin.E127**: The value of ``date_hierarchy`` refers to ``<field name>``,
  645. which does not refer to a Field.
  646. * **admin.E128**: The value of ``date_hierarchy`` must be a ``DateField`` or
  647. ``DateTimeField``.
  648. * **admin.E129**: ``<modeladmin>`` must define a ``has_<foo>_permission()``
  649. method for the ``<action>`` action.
  650. * **admin.E130**: ``__name__`` attributes of actions defined in
  651. ``<modeladmin>`` must be unique. Name ``<name>`` is not unique.
  652. ``InlineModelAdmin``
  653. ~~~~~~~~~~~~~~~~~~~~
  654. The following checks are performed on any
  655. :class:`~django.contrib.admin.InlineModelAdmin` that is registered as an
  656. inline on a :class:`~django.contrib.admin.ModelAdmin`.
  657. * **admin.E201**: Cannot exclude the field ``<field name>``, because it is the
  658. foreign key to the parent model ``<app_label>.<model>``.
  659. * **admin.E202**: ``<model>`` has no ``ForeignKey`` to ``<parent model>``./
  660. ``<model>`` has more than one ``ForeignKey`` to ``<parent model>``. You must
  661. specify a ``fk_name`` attribute.
  662. * **admin.E203**: The value of ``extra`` must be an integer.
  663. * **admin.E204**: The value of ``max_num`` must be an integer.
  664. * **admin.E205**: The value of ``min_num`` must be an integer.
  665. * **admin.E206**: The value of ``formset`` must inherit from
  666. ``BaseModelFormSet``.
  667. ``GenericInlineModelAdmin``
  668. ~~~~~~~~~~~~~~~~~~~~~~~~~~~
  669. The following checks are performed on any
  670. :class:`~django.contrib.contenttypes.admin.GenericInlineModelAdmin` that is
  671. registered as an inline on a :class:`~django.contrib.admin.ModelAdmin`.
  672. * **admin.E301**: ``'ct_field'`` references ``<label>``, which is not a field
  673. on ``<model>``.
  674. * **admin.E302**: ``'ct_fk_field'`` references ``<label>``, which is not a
  675. field on ``<model>``.
  676. * **admin.E303**: ``<model>`` has no ``GenericForeignKey``.
  677. * **admin.E304**: ``<model>`` has no ``GenericForeignKey`` using content type
  678. field ``<field name>`` and object ID field ``<field name>``.
  679. ``AdminSite``
  680. ~~~~~~~~~~~~~
  681. The following checks are performed on the default
  682. :class:`~django.contrib.admin.AdminSite`:
  683. * **admin.E401**: :mod:`django.contrib.contenttypes` must be in
  684. :setting:`INSTALLED_APPS` in order to use the admin application.
  685. * **admin.E402**: :mod:`django.contrib.auth.context_processors.auth`
  686. must be enabled in :class:`~django.template.backends.django.DjangoTemplates`
  687. (:setting:`TEMPLATES`) if using the default auth backend in order to use the
  688. admin application.
  689. * **admin.E403**: A :class:`django.template.backends.django.DjangoTemplates`
  690. instance must be configured in :setting:`TEMPLATES` in order to use the
  691. admin application.
  692. * **admin.E404**: ``django.contrib.messages.context_processors.messages``
  693. must be enabled in :class:`~django.template.backends.django.DjangoTemplates`
  694. (:setting:`TEMPLATES`) in order to use the admin application.
  695. * **admin.E405**: :mod:`django.contrib.auth` must be in
  696. :setting:`INSTALLED_APPS` in order to use the admin application.
  697. * **admin.E406**: :mod:`django.contrib.messages` must be in
  698. :setting:`INSTALLED_APPS` in order to use the admin application.
  699. * **admin.E408**:
  700. :class:`django.contrib.auth.middleware.AuthenticationMiddleware` must be in
  701. :setting:`MIDDLEWARE` in order to use the admin application.
  702. * **admin.E409**: :class:`django.contrib.messages.middleware.MessageMiddleware`
  703. must be in :setting:`MIDDLEWARE` in order to use the admin application.
  704. * **admin.E410**: :class:`django.contrib.sessions.middleware.SessionMiddleware`
  705. must be in :setting:`MIDDLEWARE` in order to use the admin application.
  706. * **admin.W411**: ``django.template.context_processors.request`` must be
  707. enabled in :class:`~django.template.backends.django.DjangoTemplates`
  708. (:setting:`TEMPLATES`) in order to use the admin navigation sidebar.
  709. ``auth``
  710. --------
  711. * **auth.E001**: ``REQUIRED_FIELDS`` must be a list or tuple.
  712. * **auth.E002**: The field named as the ``USERNAME_FIELD`` for a custom user
  713. model must not be included in ``REQUIRED_FIELDS``.
  714. * **auth.E003**: ``<field>`` must be unique because it is named as the
  715. ``USERNAME_FIELD``.
  716. * **auth.W004**: ``<field>`` is named as the ``USERNAME_FIELD``, but it is not
  717. unique.
  718. * **auth.E005**: The permission codenamed ``<codename>`` clashes with a builtin
  719. permission for model ``<model>``.
  720. * **auth.E006**: The permission codenamed ``<codename>`` is duplicated for model
  721. ``<model>``.
  722. * **auth.E007**: The :attr:`verbose_name
  723. <django.db.models.Options.verbose_name>` of model ``<model>`` must be at most
  724. 244 characters for its builtin permission names
  725. to be at most 255 characters.
  726. * **auth.E008**: The permission named ``<name>`` of model ``<model>`` is longer
  727. than 255 characters.
  728. * **auth.C009**: ``<User model>.is_anonymous`` must be an attribute or property
  729. rather than a method. Ignoring this is a security issue as anonymous users
  730. will be treated as authenticated!
  731. * **auth.C010**: ``<User model>.is_authenticated`` must be an attribute or
  732. property rather than a method. Ignoring this is a security issue as anonymous
  733. users will be treated as authenticated!
  734. * **auth.E011**: The name of model ``<model>`` must be at most 93 characters
  735. for its builtin permission names to be at most 100 characters.
  736. * **auth.E012**: The permission codenamed ``<codename>`` of model ``<model>``
  737. is longer than 100 characters.
  738. ``contenttypes``
  739. ----------------
  740. The following checks are performed when a model contains a
  741. :class:`~django.contrib.contenttypes.fields.GenericForeignKey` or
  742. :class:`~django.contrib.contenttypes.fields.GenericRelation`:
  743. * **contenttypes.E001**: The ``GenericForeignKey`` object ID references the
  744. nonexistent field ``<field>``.
  745. * **contenttypes.E002**: The ``GenericForeignKey`` content type references the
  746. nonexistent field ``<field>``.
  747. * **contenttypes.E003**: ``<field>`` is not a ``ForeignKey``.
  748. * **contenttypes.E004**: ``<field>`` is not a ``ForeignKey`` to
  749. ``contenttypes.ContentType``.
  750. * **contenttypes.E005**: Model names must be at most 100 characters.
  751. ``postgres``
  752. ------------
  753. The following checks are performed on :mod:`django.contrib.postgres` model
  754. fields:
  755. * **postgres.E001**: Base field for array has errors: ...
  756. * **postgres.E002**: Base field for array cannot be a related field.
  757. * **postgres.E003**: ``<field>`` default should be a callable instead of an
  758. instance so that it's not shared between all field instances. *This check was
  759. changed to* ``fields.E010`` *in Django 3.1*.
  760. ``sites``
  761. ---------
  762. The following checks are performed on any model using a
  763. :class:`~django.contrib.sites.managers.CurrentSiteManager`:
  764. * **sites.E001**: ``CurrentSiteManager`` could not find a field named
  765. ``<field name>``.
  766. * **sites.E002**: ``CurrentSiteManager`` cannot use ``<field>`` as it is not a
  767. foreign key or a many-to-many field.
  768. The following checks verify that :mod:`django.contrib.sites` is correctly
  769. configured:
  770. * **sites.E101**: The :setting:`SITE_ID` setting must be an integer.
  771. ``staticfiles``
  772. ---------------
  773. The following checks verify that :mod:`django.contrib.staticfiles` is correctly
  774. configured:
  775. * **staticfiles.E001**: The :setting:`STATICFILES_DIRS` setting is not a tuple
  776. or list.
  777. * **staticfiles.E002**: The :setting:`STATICFILES_DIRS` setting should not
  778. contain the :setting:`STATIC_ROOT` setting.
  779. * **staticfiles.E003**: The prefix ``<prefix>`` in the
  780. :setting:`STATICFILES_DIRS` setting must not end with a slash.
  781. * **staticfiles.W004**: The directory ``<directory>`` in the
  782. :setting:`STATICFILES_DIRS` does not exist.