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- Committer: Simon Davy
- Date: 2015-05-19 09:10:41 UTC
- Revision ID: simon.davy@canonical.com-20150519091041-y8pgzy5ayhyp3q9m
importing whitenoise 1.0.6
- files added:
- docs
- docs/changelog.rst
- whitenoise
- whitenoise.egg-info
- whitenoise/management
- whitenoise/management/commands
added
removed
whitenoise/base.py
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from __future__ import absolute_import
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from email.utils import parsedate, formatdate
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import mimetypes
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import os
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import os.path
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import re
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from time import gmtime
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from wsgiref.headers import Headers
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class StaticFile(object):
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gzip_path = None
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def __init__(self, path):
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self.path = path
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self.headers = Headers([])
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class WhiteNoise(object):
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BLOCK_SIZE = 16 * 4096
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GZIP_SUFFIX = '.gz'
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ACCEPT_GZIP_RE = re.compile(r'\bgzip\b')
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# All mimetypes starting 'text/' take a charset parameter, plus the
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# additions in this set
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MIMETYPES_WITH_CHARSET = frozenset((
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'application/javascript', 'application/xml'))
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# Ten years is what nginx sets a max age if you use 'expires max;'
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# so we'll follow its lead
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FOREVER = 10*365*24*60*60
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# Attributes that can be set by keyword args in the constructor
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config_attrs = ('max_age', 'allow_all_origins', 'charset')
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max_age = 60
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# Set 'Access-Control-Allow-Orign: *' header on all files.
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# As these are all public static files this is safe (See
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# http://www.w3.org/TR/cors/#security) and ensures that things (e.g
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# webfonts in Firefox) still work as expected when your static files are
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# served from a CDN, rather than your primary domain.
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allow_all_origins = True
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charset = 'utf-8'
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def __init__(self, application, root=None, prefix=None, **kwargs):
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for attr in self.config_attrs:
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try:
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setattr(self, attr, kwargs.pop(attr))
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except KeyError:
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pass
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if kwargs:
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raise TypeError("Unexpected keyword argument '{}'".format(
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list(kwargs.keys())[0]))
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self.application = application
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self.files = {}
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if root is not None:
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self.add_files(root, prefix)
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def __call__(self, environ, start_response):
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static_file = self.files.get(environ['PATH_INFO'])
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if static_file is None:
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return self.application(environ, start_response)
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else:
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return self.serve(static_file, environ, start_response)
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def serve(self, static_file, environ, start_response):
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method = environ['REQUEST_METHOD']
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if method != 'GET' and method != 'HEAD':
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start_response('405 Method Not Allowed', [('Allow', 'GET, HEAD')])
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return []
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if self.file_not_modified(static_file, environ):
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start_response('304 Not Modified', [])
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return []
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path, headers = self.get_path_and_headers(static_file, environ)
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start_response('200 OK', headers.items())
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if method == 'HEAD':
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return []
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file_wrapper = environ.get('wsgi.file_wrapper', self.yield_file)
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fileobj = open(path, 'rb')
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return file_wrapper(fileobj)
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def get_path_and_headers(self, static_file, environ):
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if static_file.gzip_path:
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if self.ACCEPT_GZIP_RE.search(environ.get('HTTP_ACCEPT_ENCODING', '')):
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return static_file.gzip_path, static_file.gzip_headers
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return static_file.path, static_file.headers
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def file_not_modified(self, static_file, environ):
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try:
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last_requested = environ['HTTP_IF_MODIFIED_SINCE']
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except KeyError:
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return False
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# Exact match, no need to parse
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if last_requested == static_file.headers['Last-Modified']:
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return True
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return parsedate(last_requested) >= static_file.mtime_tuple
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def yield_file(self, fileobj):
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# Only used as a fallback in case environ doesn't supply a
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# wsgi.file_wrapper
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try:
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while True:
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block = fileobj.read(self.BLOCK_SIZE)
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if block:
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yield block
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else:
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break
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finally:
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fileobj.close()
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def add_files(self, root, prefix=None, followlinks=False):
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prefix = (prefix or '').strip('/')
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prefix = '/{}/'.format(prefix) if prefix else '/'
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files = {}
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for dir_path, _, filenames in os.walk(root, followlinks=followlinks):
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for filename in filenames:
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file_path = os.path.join(dir_path, filename)
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url = prefix + os.path.relpath(file_path, root).replace('\\', '/')
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files[url] = self.get_static_file(file_path, url)
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self.find_gzipped_alternatives(files)
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self.files.update(files)
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def get_static_file(self, file_path, url):
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static_file = StaticFile(file_path)
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self.add_stat_headers(static_file, url)
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self.add_mime_headers(static_file, url)
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self.add_cache_headers(static_file, url)
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self.add_cors_headers(static_file, url)
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self.add_extra_headers(static_file, url)
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return static_file
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def add_stat_headers(self, static_file, url):
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stat = os.stat(static_file.path)
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static_file.mtime_tuple = gmtime(stat.st_mtime)
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static_file.headers['Last-Modified'] = formatdate(
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stat.st_mtime, usegmt=True)
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static_file.headers['Content-Length'] = str(stat.st_size)
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def add_mime_headers(self, static_file, url):
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mimetype, encoding = mimetypes.guess_type(static_file.path)
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mimetype = mimetype or 'application/octet-stream'
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charset = self.get_charset(mimetype, static_file, url)
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params = {'charset': charset} if charset else {}
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static_file.headers.add_header('Content-Type', mimetype, **params)
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if encoding:
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static_file.headers['Content-Encoding'] = encoding
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def get_charset(self, mimetype, static_file, url):
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if (mimetype.startswith('text/')
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or mimetype in self.MIMETYPES_WITH_CHARSET):
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return self.charset
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def add_cache_headers(self, static_file, url):
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if self.is_immutable_file(static_file, url):
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max_age = self.FOREVER
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else:
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max_age = self.max_age
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if max_age is not None:
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cache_control = 'public, max-age={}'.format(max_age)
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static_file.headers['Cache-Control'] = cache_control
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def is_immutable_file(self, static_file, url):
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"""
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This should be implemented by sub-classes (see e.g. DjangoWhiteNoise)
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"""
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return False
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def add_cors_headers(self, static_file, url):
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if self.allow_all_origins:
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static_file.headers['Access-Control-Allow-Origin'] = '*'
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def add_extra_headers(self, static_file, url):
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"""
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This is provided as a hook for sub-classes, by default a no-op
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"""
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pass
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def find_gzipped_alternatives(self, files):
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for url, static_file in files.items():
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gzip_url = url + self.GZIP_SUFFIX
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try:
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gzip_file = files[gzip_url]
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except KeyError:
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continue
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static_file.gzip_path = gzip_file.path
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static_file.headers['Vary'] = 'Accept-Encoding'
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# Copy the headers and add the appropriate encoding and length
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gzip_headers = Headers(static_file.headers.items())
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gzip_headers['Content-Encoding'] = 'gzip'
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gzip_headers['Content-Length'] = gzip_file.headers['Content-Length']
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static_file.gzip_headers = gzip_headers
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