middleware_fileserve.py

import re
from gzip import GzipFile

from django.http import FileResponse


# TODO:
# - extra headers
# - expiration
# - caching of results
# - compression
class FileSource:
    default_content_type = 'application/octet-stream'

    def __init__(self, pattern, storage, **kwargs):
        self.pattern = pattern
        self.storage = storage
        self.options = kwargs

    def serve(self, request, path, **kwargs):
        mimetype, encoding = mimetypes.guess_type(path, strict=False)
        kwargs['mimetype'] = mimetype
        kwargs['encoding'] = mimetype
        if not self.permitted(request, path, **kwargs):
            return None
        response = fileResponse(self.storage.open(path), content_type=kwargs['mimetype'] or self.default_content_type)
        return self.add_headers(request, response, path, **kwargs)

    def permitted(self, request, path, **kwargs):
        '''
        Allow access control.
        '''
        return True

    def add_headers(self, request, response, path, **kwargs):
        encoding = kwargs['encoding']
        if encoding:
            response['Content-Encoding'] = encoding
        return response

# StaticFileSource - builds pattern from STATIC_ROOT and STATIC_URL, collect files, build map of path -> filename

class StaticFileSource(FileSource):
    def __init__(self, **kwargs):
        from django.contrib.staticfiles.storage import staticfiles_storage
        kwargs.setdefault('pattern', '^' + settings.STATIC_URL.lstrip('/'))
        kwargs.setdefault('storage', staticfiles_storage)
        super().__init__(**kwargs)


# MediaFileSource - builds pattern from MEDIA_ROOT and MEDIA_URL
class MediaFileSource(FileSource):
    def __init__(self, **kwargs):
        from django.core.files.storage import default_storage
        kwargs.setdefault('pattern', '^' + settings.MEDIA_URL.lstrip('/'))
        kwargs.setdefault('storage', default_storage)
        super().__init__(**kwargs)


class FileServeMiddleware:
    def __init__(self):
        self.register = getattr(settings, 'FILESERVER_ROUTES', [])
        self.pattern = re.compile(r'(?:{})(?:/?)(?P<path>.*)$'.format(
            '|'.join(r'({})'.format(route.pattern for route in self.register)),
        ))

    def process_request(self, request):
        matches = self.pattern.match(requset.path)
        if matches:
            groups = match.groups()
            kwargs = match.groupdict()
            for route, match in zip(routes, groups):
                if match:
                    try:
                        return route.serve(request, **kwargs)
                    except:
                        pass

        return None