import hashlib import json import os import posixpath import re from collections import OrderedDict from urllib.parse import unquote, urldefrag, urlsplit, urlunsplit from django.conf import settings from django.contrib.staticfiles.utils import check_settings, matches_patterns from django.core.cache import ( InvalidCacheBackendError, cache as default_cache, caches, ) from django.core.exceptions import ImproperlyConfigured from django.core.files.base import ContentFile from django.core.files.storage import FileSystemStorage, get_storage_class from django.utils.encoding import force_bytes from django.utils.functional import LazyObject class StaticFilesStorage(FileSystemStorage): """ Standard file system storage for static files. The defaults for ``location`` and ``base_url`` are ``STATIC_ROOT`` and ``STATIC_URL``. """ def __init__(self, location=None, base_url=None, *args, **kwargs): if location is None: location = settings.STATIC_ROOT if base_url is None: base_url = settings.STATIC_URL check_settings(base_url) super().__init__(location, base_url, *args, **kwargs) # FileSystemStorage fallbacks to MEDIA_ROOT when location # is empty, so we restore the empty value. if not location: self.base_location = None self.location = None def path(self, name): if not self.location: raise ImproperlyConfigured("You're using the staticfiles app " "without having set the STATIC_ROOT " "setting to a filesystem path.") return super().path(name) class HashedFilesMixin: default_template = """url("%s")""" max_post_process_passes = 5 patterns = ( ("*.css", ( r"""(url\(['"]{0,1}\s*(.*?)["']{0,1}\))""", (r"""(@import\s*["']\s*(.*?)["'])""", """@import url("%s")"""), )), ) def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) self._patterns = OrderedDict() self.hashed_files = {} for extension, patterns in self.patterns: for pattern in patterns: if isinstance(pattern, (tuple, list)): pattern, template = pattern else: template = self.default_template compiled = re.compile(pattern, re.IGNORECASE) self._patterns.setdefault(extension, []).append((compiled, template)) def file_hash(self, name, content=None): """ Return a hash of the file with the given name and optional content. """ if content is None: return None md5 = hashlib.md5() for chunk in content.chunks(): md5.update(chunk) return md5.hexdigest()[:12] def hashed_name(self, name, content=None, filename=None): # `filename` is the name of file to hash if `content` isn't given. # `name` is the base name to construct the new hashed filename from. parsed_name = urlsplit(unquote(name)) clean_name = parsed_name.path.strip() if filename: filename = urlsplit(unquote(filename)).path.strip() filename = filename or clean_name opened = False if content is None: if not self.exists(filename): raise ValueError("The file '%s' could not be found with %r." % (filename, self)) try: content = self.open(filename) except IOError: # Handle directory paths and fragments return name opened = True try: file_hash = self.file_hash(clean_name, content) finally: if opened: content.close() path, filename = os.path.split(clean_name) root, ext = os.path.splitext(filename) if file_hash is not None: file_hash = ".%s" % file_hash hashed_name = os.path.join(path, "%s%s%s" % (root, file_hash, ext)) unparsed_name = list(parsed_name) unparsed_name[2] = hashed_name # Special casing for a @font-face hack, like url(myfont.eot?#iefix") # http://www.fontspring.com/blog/the-new-bulletproof-font-face-syntax if '?#' in name and not unparsed_name[3]: unparsed_name[2] += '?' return urlunsplit(unparsed_name) def _url(self, hashed_name_func, name, force=False, hashed_files=None): """ Return the non-hashed URL in DEBUG mode. """ if settings.DEBUG and not force: hashed_name, fragment = name, '' else: clean_name, fragment = urldefrag(name) if urlsplit(clean_name).path.endswith('/'): # don't hash paths hashed_name = name else: args = (clean_name,) if hashed_files is not None: args += (hashed_files,) hashed_name = hashed_name_func(*args) final_url = super().url(hashed_name) # Special casing for a @font-face hack, like url(myfont.eot?#iefix") # http://www.fontspring.com/blog/the-new-bulletproof-font-face-syntax query_fragment = '?#' in name # [sic!] if fragment or query_fragment: urlparts = list(urlsplit(final_url)) if fragment and not urlparts[4]: urlparts[4] = fragment if query_fragment and not urlparts[3]: urlparts[2] += '?' final_url = urlunsplit(urlparts) return unquote(final_url) def url(self, name, force=False): """ Return the non-hashed URL in DEBUG mode. """ return self._url(self.stored_name, name, force) def url_converter(self, name, hashed_files, template=None): """ Return the custom URL converter for the given file name. """ if template is None: template = self.default_template def converter(matchobj): """ Convert the matched URL to a normalized and hashed URL. This requires figuring out which files the matched URL resolves to and calling the url() method of the storage. """ matched, url = matchobj.groups() # Ignore absolute/protocol-relative and data-uri URLs. if re.match(r'^[a-z]+:', url): return matched # Ignore absolute URLs that don't point to a static file (dynamic # CSS / JS?). Note that STATIC_URL cannot be empty. if url.startswith('/') and not url.startswith(settings.STATIC_URL): return matched # Strip off the fragment so a path-like fragment won't interfere. url_path, fragment = urldefrag(url) if url_path.startswith('/'): # Otherwise the condition above would have returned prematurely. assert url_path.startswith(settings.STATIC_URL) target_name = url_path[len(settings.STATIC_URL):] else: # We're using the posixpath module to mix paths and URLs conveniently. source_name = name if os.sep == '/' else name.replace(os.sep, '/') target_name = posixpath.join(posixpath.dirname(source_name), url_path) # Determine the hashed name of the target file with the storage backend. hashed_url = self._url( self._stored_name, unquote(target_name), force=True, hashed_files=hashed_files, ) transformed_url = '/'.join(url_path.split('/')[:-1] + hashed_url.split('/')[-1:]) # Restore the fragment that was stripped off earlier. if fragment: transformed_url += ('?#' if '?#' in url else '#') + fragment # Return the hashed version to the file return template % unquote(transformed_url) return converter def post_process(self, paths, dry_run=False, **options): """ Post process the given OrderedDict of files (called from collectstatic). Processing is actually two separate operations: 1. renaming files to include a hash of their content for cache-busting, and copying those files to the target storage. 2. adjusting files which contain references to other files so they refer to the cache-busting filenames. If either of these are performed on a file, then that file is considered post-processed. """ # don't even dare to process the files if we're in dry run mode if dry_run: return # where to store the new paths hashed_files = OrderedDict() # build a list of adjustable files adjustable_paths = [ path for path in paths if matches_patterns(path, self._patterns) ] # Do a single pass first. Post-process all files once, then repeat for # adjustable files. for name, hashed_name, processed, _ in self._post_process(paths, adjustable_paths, hashed_files): yield name, hashed_name, processed paths = {path: paths[path] for path in adjustable_paths} for i in range(self.max_post_process_passes): substitutions = False for name, hashed_name, processed, subst in self._post_process(paths, adjustable_paths, hashed_files): yield name, hashed_name, processed substitutions = substitutions or subst if not substitutions: break if substitutions: yield 'All', None, RuntimeError('Max post-process passes exceeded.') # Store the processed paths self.hashed_files.update(hashed_files) def _post_process(self, paths, adjustable_paths, hashed_files): # Sort the files by directory level def path_level(name): return len(name.split(os.sep)) for name in sorted(paths, key=path_level, reverse=True): substitutions = True # use the original, local file, not the copied-but-unprocessed # file, which might be somewhere far away, like S3 storage, path = paths[name] with storage.open(path) as original_file: cleaned_name = self.clean_name(name) hash_key = self.hash_key(cleaned_name) # generate the hash with the original content, even for # adjustable files. if hash_key not in hashed_files: hashed_name = self.hashed_name(name, original_file) else: hashed_name = hashed_files[hash_key] # then get the original's file content.. if hasattr(original_file, 'seek'): original_file.seek(0) hashed_file_exists = self.exists(hashed_name) processed = False # ..to apply each replacement pattern to the content if name in adjustable_paths: old_hashed_name = hashed_name content = original_file.read().decode(settings.FILE_CHARSET) for extension, patterns in self._patterns.items(): if matches_patterns(path, (extension,)): for pattern, template in patterns: converter = self.url_converter(name, hashed_files, template) try: content = pattern.sub(converter, content) except ValueError as exc: yield name, None, exc, False if hashed_file_exists: self.delete(hashed_name) # then save the processed result content_file = ContentFile(force_bytes(content)) # Save intermediate file for reference saved_name = self._save(hashed_name, content_file) hashed_name = self.hashed_name(name, content_file) if self.exists(hashed_name): self.delete(hashed_name) saved_name = self._save(hashed_name, content_file) hashed_name = self.clean_name(saved_name) # If the file hash stayed the same, this file didn't change if old_hashed_name == hashed_name: substitutions = False processed = True if not processed: # or handle the case in which neither processing nor # a change to the original file happened if not hashed_file_exists: processed = True saved_name = self._save(hashed_name, original_file) hashed_name = self.clean_name(saved_name) # and then set the cache accordingly hashed_files[hash_key] = hashed_name yield name, hashed_name, processed, substitutions def clean_name(self, name): return name.replace('\\', '/') def hash_key(self, name): return name def _stored_name(self, name, hashed_files): # Normalize the path to avoid multiple names for the same file like # ../foo/bar.css and ../foo/../foo/bar.css which normalize to the same # path. name = posixpath.normpath(name) cleaned_name = self.clean_name(name) hash_key = self.hash_key(cleaned_name) cache_name = hashed_files.get(hash_key) if cache_name is None: cache_name = self.clean_name(self.hashed_name(name)) return cache_name def stored_name(self, name): cleaned_name = self.clean_name(name) hash_key = self.hash_key(cleaned_name) cache_name = self.hashed_files.get(hash_key) if cache_name: return cache_name # No cached name found, recalculate it from the files. intermediate_name = name for i in range(self.max_post_process_passes + 1): cache_name = self.clean_name( self.hashed_name(name, content=None, filename=intermediate_name) ) if intermediate_name == cache_name: # Store the hashed name if there was a miss. self.hashed_files[hash_key] = cache_name return cache_name else: # Move on to the next intermediate file. intermediate_name = cache_name # If the cache name can't be determined after the max number of passes, # the intermediate files on disk may be corrupt; avoid an infinite loop. raise ValueError("The name '%s' could not be hashed with %r." % (name, self)) class ManifestFilesMixin(HashedFilesMixin): manifest_version = '1.0' # the manifest format standard manifest_name = 'staticfiles.json' manifest_strict = True def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) self.hashed_files = self.load_manifest() def read_manifest(self): try: with self.open(self.manifest_name) as manifest: return manifest.read().decode() except IOError: return None def load_manifest(self): content = self.read_manifest() if content is None: return OrderedDict() try: stored = json.loads(content, object_pairs_hook=OrderedDict) except ValueError: pass else: version = stored.get('version') if version == '1.0': return stored.get('paths', OrderedDict()) raise ValueError("Couldn't load manifest '%s' (version %s)" % (self.manifest_name, self.manifest_version)) def post_process(self, *args, **kwargs): self.hashed_files = OrderedDict() yield from super().post_process(*args, **kwargs) self.save_manifest() def save_manifest(self): payload = {'paths': self.hashed_files, 'version': self.manifest_version} if self.exists(self.manifest_name): self.delete(self.manifest_name) contents = json.dumps(payload).encode() self._save(self.manifest_name, ContentFile(contents)) def stored_name(self, name): parsed_name = urlsplit(unquote(name)) clean_name = parsed_name.path.strip() hash_key = self.hash_key(clean_name) cache_name = self.hashed_files.get(hash_key) if cache_name is None: if self.manifest_strict: raise ValueError("Missing staticfiles manifest entry for '%s'" % clean_name) cache_name = self.clean_name(self.hashed_name(name)) unparsed_name = list(parsed_name) unparsed_name[2] = cache_name # Special casing for a @font-face hack, like url(myfont.eot?#iefix") # http://www.fontspring.com/blog/the-new-bulletproof-font-face-syntax if '?#' in name and not unparsed_name[3]: unparsed_name[2] += '?' return urlunsplit(unparsed_name) class _MappingCache: """ A small dict-like wrapper for a given cache backend instance. """ def __init__(self, cache): self.cache = cache def __setitem__(self, key, value): self.cache.set(key, value) def __getitem__(self, key): value = self.cache.get(key) if value is None: raise KeyError("Couldn't find a file name '%s'" % key) return value def clear(self): self.cache.clear() def update(self, data): self.cache.set_many(data) def get(self, key, default=None): try: return self[key] except KeyError: return default class CachedFilesMixin(HashedFilesMixin): def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) try: self.hashed_files = _MappingCache(caches['staticfiles']) except InvalidCacheBackendError: # Use the default backend self.hashed_files = _MappingCache(default_cache) def hash_key(self, name): key = hashlib.md5(force_bytes(self.clean_name(name))).hexdigest() return 'staticfiles:%s' % key class CachedStaticFilesStorage(CachedFilesMixin, StaticFilesStorage): """ A static file system storage backend which also saves hashed copies of the files it saves. """ pass class ManifestStaticFilesStorage(ManifestFilesMixin, StaticFilesStorage): """ A static file system storage backend which also saves hashed copies of the files it saves. """ pass class ConfiguredStorage(LazyObject): def _setup(self): self._wrapped = get_storage_class(settings.STATICFILES_STORAGE)() staticfiles_storage = ConfiguredStorage()