django/contrib/staticfiles/finders.py
import functools
import os
from django.apps import apps
from django.conf import settings
from django.contrib.staticfiles import utils
from django.core.checks import Error, Warning
from django.core.exceptions import ImproperlyConfigured
from django.core.files.storage import FileSystemStorage, Storage, default_storage
from django.utils._os import safe_join
from django.utils.functional import LazyObject, empty
from django.utils.module_loading import import_string
# To keep track on which directories the finder has searched the static files.
searched_locations = []
class BaseFinder:
"""
A base file finder to be used for custom staticfiles finder classes.
"""
def check(self, **kwargs):
raise NotImplementedError(
"subclasses may provide a check() method to verify the finder is "
"configured correctly."
)
def find(self, path, all=False):
"""
Given a relative file path, find an absolute file path.
If the ``all`` parameter is False (default) return only the first found
file path; if True, return a list of all found files paths.
"""
raise NotImplementedError(
"subclasses of BaseFinder must provide a find() method"
)
def list(self, ignore_patterns):
"""
Given an optional list of paths to ignore, return a two item iterable
consisting of the relative path and storage instance.
"""
raise NotImplementedError(
"subclasses of BaseFinder must provide a list() method"
)
class FileSystemFinder(BaseFinder):
"""
A static files finder that uses the ``STATICFILES_DIRS`` setting
to locate files.
"""
def __init__(self, app_names=None, *args, **kwargs):
# List of locations with static files
self.locations = []
# Maps dir paths to an appropriate storage instance
self.storages = {}
for root in settings.STATICFILES_DIRS:
if isinstance(root, (list, tuple)):
prefix, root = root
else:
prefix = ""
if (prefix, root) not in self.locations:
self.locations.append((prefix, root))
for prefix, root in self.locations:
filesystem_storage = FileSystemStorage(location=root)
filesystem_storage.prefix = prefix
self.storages[root] = filesystem_storage
super().__init__(*args, **kwargs)
def check(self, **kwargs):
errors = []
if not isinstance(settings.STATICFILES_DIRS, (list, tuple)):
errors.append(
Error(
"The STATICFILES_DIRS setting is not a tuple or list.",
hint="Perhaps you forgot a trailing comma?",
id="staticfiles.E001",
)
)
return errors
for root in settings.STATICFILES_DIRS:
if isinstance(root, (list, tuple)):
prefix, root = root
if prefix.endswith("/"):
errors.append(
Error(
"The prefix %r in the STATICFILES_DIRS setting must "
"not end with a slash." % prefix,
id="staticfiles.E003",
)
)
if settings.STATIC_ROOT and os.path.abspath(
settings.STATIC_ROOT
) == os.path.abspath(root):
errors.append(
Error(
"The STATICFILES_DIRS setting should not contain the "
"STATIC_ROOT setting.",
id="staticfiles.E002",
)
)
if not os.path.isdir(root):
errors.append(
Warning(
f"The directory '{root}' in the STATICFILES_DIRS setting "
f"does not exist.",
id="staticfiles.W004",
)
)
return errors
def find(self, path, all=False):
"""
Look for files in the extra locations as defined in STATICFILES_DIRS.
"""
matches = []
for prefix, root in self.locations:
if root not in searched_locations:
searched_locations.append(root)
matched_path = self.find_location(root, path, prefix)
if matched_path:
if not all:
return matched_path
matches.append(matched_path)
return matches
def find_location(self, root, path, prefix=None):
"""
Find a requested static file in a location and return the found
absolute path (or ``None`` if no match).
"""
if prefix:
prefix = "%s%s" % (prefix, os.sep)
if not path.startswith(prefix):
return None
path = path.removeprefix(prefix)
path = safe_join(root, path)
if os.path.exists(path):
return path
def list(self, ignore_patterns):
"""
List all files in all locations.
"""
for prefix, root in self.locations:
# Skip nonexistent directories.
if os.path.isdir(root):
storage = self.storages[root]
for path in utils.get_files(storage, ignore_patterns):
yield path, storage
class AppDirectoriesFinder(BaseFinder):
"""
A static files finder that looks in the directory of each app as
specified in the source_dir attribute.
"""
storage_class = FileSystemStorage
source_dir = "static"
def __init__(self, app_names=None, *args, **kwargs):
# The list of apps that are handled
self.apps = []
# Mapping of app names to storage instances
self.storages = {}
app_configs = apps.get_app_configs()
if app_names:
app_names = set(app_names)
app_configs = [ac for ac in app_configs if ac.name in app_names]
for app_config in app_configs:
app_storage = self.storage_class(
os.path.join(app_config.path, self.source_dir)
)
if os.path.isdir(app_storage.location):
self.storages[app_config.name] = app_storage
if app_config.name not in self.apps:
self.apps.append(app_config.name)
super().__init__(*args, **kwargs)
def list(self, ignore_patterns):
"""
List all files in all app storages.
"""
for storage in self.storages.values():
if storage.exists(""): # check if storage location exists
for path in utils.get_files(storage, ignore_patterns):
yield path, storage
def find(self, path, all=False):
"""
Look for files in the app directories.
"""
matches = []
for app in self.apps:
app_location = self.storages[app].location
if app_location not in searched_locations:
searched_locations.append(app_location)
match = self.find_in_app(app, path)
if match:
if not all:
return match
matches.append(match)
return matches
def find_in_app(self, app, path):
"""
Find a requested static file in an app's static locations.
"""
storage = self.storages.get(app)
# Only try to find a file if the source dir actually exists.
if storage and storage.exists(path):
matched_path = storage.path(path)
if matched_path:
return matched_path
class BaseStorageFinder(BaseFinder):
"""
A base static files finder to be used to extended
with an own storage class.
"""
storage = None
def __init__(self, storage=None, *args, **kwargs):
if storage is not None:
self.storage = storage
if self.storage is None:
raise ImproperlyConfigured(
"The staticfiles storage finder %r "
"doesn't have a storage class "
"assigned." % self.__class__
)
# Make sure we have a storage instance here.
if not isinstance(self.storage, (Storage, LazyObject)):
self.storage = self.storage()
super().__init__(*args, **kwargs)
def find(self, path, all=False):
"""
Look for files in the default file storage, if it's local.
"""
try:
self.storage.path("")
except NotImplementedError:
pass
else:
if self.storage.location not in searched_locations:
searched_locations.append(self.storage.location)
if self.storage.exists(path):
match = self.storage.path(path)
if all:
match = [match]
return match
return []
def list(self, ignore_patterns):
"""
List all files of the storage.
"""
for path in utils.get_files(self.storage, ignore_patterns):
yield path, self.storage
class DefaultStorageFinder(BaseStorageFinder):
"""
A static files finder that uses the default storage backend.
"""
storage = default_storage
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
base_location = getattr(self.storage, "base_location", empty)
if not base_location:
raise ImproperlyConfigured(
"The storage backend of the "
"staticfiles finder %r doesn't have "
"a valid location." % self.__class__
)
def find(path, all=False):
"""
Find a static file with the given path using all enabled finders.
If ``all`` is ``False`` (default), return the first matching
absolute path (or ``None`` if no match). Otherwise return a list.
"""
searched_locations[:] = []
matches = []
for finder in get_finders():
result = finder.find(path, all=all)
if not all and result:
return result
if not isinstance(result, (list, tuple)):
result = [result]
matches.extend(result)
if matches:
return matches
# No match.
return [] if all else None
def get_finders():
for finder_path in settings.STATICFILES_FINDERS:
yield get_finder(finder_path)
@functools.cache
def get_finder(import_path):
"""
Import the staticfiles finder class described by import_path, where
import_path is the full Python path to the class.
"""
Finder = import_string(import_path)
if not issubclass(Finder, BaseFinder):
raise ImproperlyConfigured(
'Finder "%s" is not a subclass of "%s"' % (Finder, BaseFinder)
)
return Finder()