Django文件存储 默认存储系统解析

 from django.db import models from django.core.files.storage import FileSystemStorage fs = FileSystemStorage(location='/media/photos') class Car(models.Model): ... photo = models.ImageField(storage=fs)

 >>> from django.core.files.storage import default_storage >>> from django.core.files.base import ContentFile >>> path = default_storage.save('/path/to/file', ContentFile('new content')) >>> path '/path/to/file' >>> default_storage.size(path) 11 >>> default_storage.open(path).read() 'new co<p style="color:transparent">来源gao!%daima.com搞$代*!码$网</p>ntent' >>> default_storage.delete(path) >>> default_storage.exists(path) False

 def _save(self, name, content): full_path = self.path(name) # Create any intermediate directories that do not exist. # Note that there is a race between os.path.exists and os.makedirs: # if os.makedirs fails with EEXIST, the directory was created # concurrently, and we can continue normally. Refs #16082. directory = os.path.dirname(full_path) if not os.path.exists(directory): try: if self.directory_permissions_mode is not None: # os.makedirs applies the global umask, so we reset it, # for consistency with file_permissions_mode behavior. old_umask = os.umask(0) try: os.makedirs(directory, self.directory_permissions_mode) finally: os.umask(old_umask) else: os.makedirs(directory) except OSError as e: if e.errno != errno.EEXIST: raise if not os.path.isdir(directory): raise IOError("%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: # This fun binary flag incantation makes os.open throw an # OSError if the file already exists before we open it. flags = (os.O_WRONLY | os.O_CREAT | os.O_EXCL | getattr(os, 'O_BINARY', 0)) # The current umask value is masked out by os.open! fd = os.open(full_path, 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 OSError as e: if e.errno == errno.EEXIST: # Ooops, the file exists. We need a new file name. name = self.get_available_name(name) full_path = self.path(name) else: raise 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) # Store filenames with forward slashes, even on Windows. return force_text(name.replace('\\', '/'))