URLResolver

This class maps URL paths to view functions and handles the reverse process of generating URLs from view identifiers. It supports nested URL configurations, namespaces, and application-specific routing by recursively resolving patterns against a provided URL configuration module. Additionally, it manages thread-safe population of lookup dictionaries to facilitate efficient URL reversing and pattern matching.

Attributes

Attribute	Type	Description
pattern	[URLPattern](urlpattern.md?sid=django_urls_resolvers_urlpattern)	The URL pattern object used to match the incoming request path.
urlconf_name	`string	object
callback	`callable	null` = null
default_kwargs	dict = {}	A dictionary of default keyword arguments to be passed to the retrieved view function.
namespace	`string	null`
app_name	`string	null`
reverse_dict	[MultiValueDict](../../utils/datastructures/multivaluedict.md?sid=django_utils_datastructures_multivaluedict)	A mapping of URL names and callables to their respective path patterns and defaults, used for reversing URLs.
namespace_dict	dict	A mapping of namespaces to their corresponding prefixes and sub-resolver objects.
app_dict	dict	A mapping of application names to lists of their registered namespaces.
urlconf_module	module	The imported Python module containing the URL configuration.
url_patterns	list	The list of URL patterns defined in the associated URLconf module.

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Constructor

Signature

def URLResolver(
    pattern: object,
    urlconf_name: string | object,
    default_kwargs: dict = None,
    app_name: string = None,
    namespace: string = None
) - > null

Parameters

Name	Type	Description
pattern	object	The pattern object used for matching URLs.
urlconf_name	`string	object`
default_kwargs	dict = None	Additional keyword arguments to be passed to the view function.
app_name	string = None	The name of the application for the URL configuration.
namespace	string = None	The instance namespace for the URL configuration.

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Methods

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check()

@classmethod
def check() - > array

Validates the URL patterns within the resolver and its associated pattern object to identify configuration errors.

Returns

Type	Description
array	A list of system check messages or errors found in the URL configuration.

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reverse_dict()

@classmethod
def reverse_dict() - > object

Retrieves the mapping of view names to URL patterns for the current language, triggering population if necessary.

Returns

Type	Description
object	A MultiValueDict containing URL patterns indexed by view name or callback.

---

namespace_dict()

@classmethod
def namespace_dict() - > object

Retrieves the mapping of namespaces to their corresponding URL prefixes and resolvers for the current language.

Returns

Type	Description
object	A dictionary where keys are namespace strings and values are tuples of (prefix, resolver).

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app_dict()

@classmethod
def app_dict() - > object

Retrieves the mapping of application names to their registered namespaces for the current language.

Returns

Type	Description
object	A dictionary where keys are application names and values are lists of associated namespaces.

---

resolve()

@classmethod
def resolve(
    path: string
) - > object

Attempts to match a URL path against the registered patterns and returns the matching view and arguments.

Parameters

Name	Type	Description
path	string	The URL path string to be resolved into a view.

Returns

Type	Description
object	A ResolverMatch object containing the view function, arguments, and URL metadata.

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urlconf_module()

@classmethod
def urlconf_module() - > module

Imports and returns the Python module containing the URL patterns defined for this resolver.

Returns

Type	Description
module	The Python module object containing the urlpatterns.

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url_patterns()

@classmethod
def url_patterns() - > array

Retrieves the list of URL patterns from the configured module, raising an error if the module is misconfigured.

Returns

Type	Description
array	A list of URLPattern or URLResolver instances.

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resolve_error_handler()

@classmethod
def resolve_error_handler(
    view_type: string
) - > callable

Locates the appropriate error handler view for a specific HTTP error type (e.g., 404, 500).

Parameters

Name	Type	Description
view_type	string	The HTTP error code or type used to look up the handler (e.g., '404').

Returns

Type	Description
callable	The view function responsible for handling the specified error type.

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reverse()

@classmethod
def reverse(
    lookup_view: string,
    args: array,
    kwargs: object
) - > string

Generates a URL path from a view name or callback by performing a reverse lookup with an empty prefix.

Parameters

Name	Type	Description
lookup_view	string	The name of the view or the view function to reverse.
args	array	Positional arguments to be interpolated into the URL pattern.
kwargs	object	Keyword arguments to be interpolated into the URL pattern.

Returns

Type	Description
string	The absolute URL path corresponding to the provided view and arguments.

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