# Django 4.2.11 documentation

# Source code for django.core.files.storage.filesystem

    import os
    from datetime import datetime, timezone
    from urllib.parse import urljoin

    from django.conf import settings
    from django.core.files import File, locks
    from django.core.files.move import file_move_safe
    from django.core.signals import setting_changed
    from django.utils._os import safe_join
    from django.utils.deconstruct import deconstructible
    from django.utils.encoding import filepath_to_uri
    from django.utils.functional import cached_property

    from .base import Storage
    from .mixins import StorageSettingsMixin

    @deconstructible(path="django.core.files.storage.FileSystemStorage")
    class FileSystemStorage(Storage, StorageSettingsMixin):
        """
        Standard filesystem storage
        """

        # The combination of O_CREAT and O_EXCL makes os.open() raise OSError if
        # the file already exists before it's opened.
        OS_OPEN_FLAGS = os.O_WRONLY | os.O_CREAT | os.O_EXCL | getattr(os, "O_BINARY", 0)

        def __init__(
            self,
            location=None,
            base_url=None,
            file_permissions_mode=None,
            directory_permissions_mode=None,
        ):
            self._location = location
            self._base_url = base_url
            self._file_permissions_mode = file_permissions_mode
            self._directory_permissions_mode = directory_permissions_mode
            setting_changed.connect(self._clear_cached_properties)

        @cached_property
        def base_location(self):
            return self._value_or_setting(self._location, settings.MEDIA_ROOT)

        @cached_property
        def location(self):
            return os.path.abspath(self.base_location)

        @cached_property
        def base_url(self):
            if self._base_url is not None and not self._base_url.endswith("/"):
                self._base_url += "/"
            return self._value_or_setting(self._base_url, settings.MEDIA_URL)

        @cached_property
        def file_permissions_mode(self):
            return self._value_or_setting(
                self._file_permissions_mode, settings.FILE_UPLOAD_PERMISSIONS
            )

        @cached_property
        def directory_permissions_mode(self):
            return self._value_or_setting(
                self._directory_permissions_mode, settings.FILE_UPLOAD_DIRECTORY_PERMISSIONS
            )

        def _open(self, name, mode="rb"):
            return File(open(self.path(name), mode))

        def _save(self, name, content):
            full_path = self.path(name)

            # Create any intermediate directories that do not exist.
            directory = os.path.dirname(full_path)
            try:
                if self.directory_permissions_mode is not None:
                    # Set the umask because os.makedirs() doesn't apply the "mode"
                    # argument to intermediate-level directories.
                    old_umask = os.umask(0o777 & ~self.directory_permissions_mode)
                    try:
                        os.makedirs(
                            directory, self.directory_permissions_mode, exist_ok=True
                        )
                    finally:
                        os.umask(old_umask)
                else:
                    os.makedirs(directory, exist_ok=True)
            except FileExistsError:
                raise FileExistsError("%s exists and is not a directory." % directory)

            # There's a potential race condition between get_available_name and
            # saving the file; it's possible that two threads might return the
            # same name, at which point all sorts of fun happens. So we need to
            # try to create the file, but if it already exists we have to go back
            # to get_available_name() and try again.

            while True:
                try:
                    # This file has a file path that we can move.
                    if hasattr(content, "temporary_file_path"):
                        file_move_safe(content.temporary_file_path(), full_path)

                    # This is a normal uploadedfile that we can stream.
                    else:
                        # The current umask value is masked out by os.open!
                        fd = os.open(full_path, self.OS_OPEN_FLAGS, 0o666)
                        _file = None
                        try:
                            locks.lock(fd, locks.LOCK_EX)
                            for chunk in content.chunks():
                                if _file is None:
                                    mode = "wb" if isinstance(chunk, bytes) else "wt"
                                    _file = os.fdopen(fd, mode)
                                _file.write(chunk)
                        finally:
                            locks.unlock(fd)
                            if _file is not None:
                                _file.close()
                            else:
                                os.close(fd)
                except FileExistsError:
                    # A new name is needed if the file exists.
                    name = self.get_available_name(name)
                    full_path = self.path(name)
                else:
                    # OK, the file save worked. Break out of the loop.
                    break

            if self.file_permissions_mode is not None:
                os.chmod(full_path, self.file_permissions_mode)

            # Ensure the saved path is always relative to the storage root.
            name = os.path.relpath(full_path, self.location)
            # Ensure the moved file has the same gid as the storage root.
            self._ensure_location_group_id(full_path)
            # Store filenames with forward slashes, even on Windows.
            return str(name).replace("\\", "/")

        def _ensure_location_group_id(self, full_path):
            if os.name == "posix":
                file_gid = os.stat(full_path).st_gid
                location_gid = os.stat(self.location).st_gid
                if file_gid != location_gid:
                    try:
                        os.chown(full_path, uid=-1, gid=location_gid)
                    except PermissionError:
                        pass

        def delete(self, name):
            if not name:
                raise ValueError("The name must be given to delete().")
            name = self.path(name)
            # If the file or directory exists, delete it from the filesystem.
            try:
                if os.path.isdir(name):
                    os.rmdir(name)
                else:
                    os.remove(name)
            except FileNotFoundError:
                # FileNotFoundError is raised if the file or directory was removed
                # concurrently.
                pass

        def exists(self, name):
            return os.path.lexists(self.path(name))

        def listdir(self, path):
            path = self.path(path)
            directories, files = [], []
            with os.scandir(path) as entries:
                for entry in entries:
                    if entry.is_dir():
                        directories.append(entry.name)
                    else:
                        files.append(entry.name)
            return directories, files

        def path(self, name):
            return safe_join(self.location, name)

        def size(self, name):
            return os.path.getsize(self.path(name))

        def url(self, name):
            if self.base_url is None:
                raise ValueError("This file is not accessible via a URL.")
            url = filepath_to_uri(name)
            if url is not None:
                url = url.lstrip("/")
            return urljoin(self.base_url, url)

        def _datetime_from_timestamp(self, ts):
            """
            If timezone support is enabled, make an aware datetime object in UTC;
            otherwise make a naive one in the local timezone.
            """
            tz = timezone.utc if settings.USE_TZ else None
            return datetime.fromtimestamp(ts, tz=tz)

        def get_accessed_time(self, name):
            return self._datetime_from_timestamp(os.path.getatime(self.path(name)))

        def get_created_time(self, name):
            return self._datetime_from_timestamp(os.path.getctime(self.path(name)))

        def get_modified_time(self, name):
            return self._datetime_from_timestamp(os.path.getmtime(self.path(name)))