sanic/sanic/static.py
2017-09-27 01:24:49 -07:00

126 lines
5.4 KiB
Python

from mimetypes import guess_type
from os import path
from re import sub
from time import strftime, gmtime
from urllib.parse import unquote
from aiofiles.os import stat
from sanic.exceptions import (
ContentRangeError,
FileNotFound,
HeaderNotFound,
InvalidUsage,
)
from sanic.handlers import ContentRangeHandler
from sanic.response import file, file_stream, HTTPResponse
def register(app, uri, file_or_directory, pattern,
use_modified_since, use_content_range,
stream_large_files, name='static', host=None):
# TODO: Though sanic is not a file server, I feel like we should at least
# make a good effort here. Modified-since is nice, but we could
# also look into etags, expires, and caching
"""
Register a static directory handler with Sanic by adding a route to the
router and registering a handler.
:param app: Sanic
:param file_or_directory: File or directory path to serve from
:param uri: URL to serve from
:param pattern: regular expression used to match files in the URL
:param use_modified_since: If true, send file modified time, and return
not modified if the browser's matches the
server's
:param use_content_range: If true, process header for range requests
and sends the file part that is requested
:param stream_large_files: If true, use the file_stream() handler rather
than the file() handler to send the file
If this is an integer, this represents the
threshold size to switch to file_stream()
:param name: user defined name used for url_for
"""
# If we're not trying to match a file directly,
# serve from the folder
if not path.isfile(file_or_directory):
uri += '<file_uri:' + pattern + '>'
async def _handler(request, file_uri=None):
# Using this to determine if the URL is trying to break out of the path
# served. os.path.realpath seems to be very slow
if file_uri and '../' in file_uri:
raise InvalidUsage("Invalid URL")
# Merge served directory and requested file if provided
# Strip all / that in the beginning of the URL to help prevent python
# from herping a derp and treating the uri as an absolute path
root_path = file_path = file_or_directory
if file_uri:
file_path = path.join(
file_or_directory, sub('^[/]*', '', file_uri))
# URL decode the path sent by the browser otherwise we won't be able to
# match filenames which got encoded (filenames with spaces etc)
file_path = path.abspath(unquote(file_path))
if not file_path.startswith(path.abspath(unquote(root_path))):
raise FileNotFound('File not found',
path=file_or_directory,
relative_url=file_uri)
try:
headers = {}
# Check if the client has been sent this file before
# and it has not been modified since
stats = None
if use_modified_since:
stats = await stat(file_path)
modified_since = strftime(
'%a, %d %b %Y %H:%M:%S GMT', gmtime(stats.st_mtime))
if request.headers.get('If-Modified-Since') == modified_since:
return HTTPResponse(status=304)
headers['Last-Modified'] = modified_since
_range = None
if use_content_range:
_range = None
if not stats:
stats = await stat(file_path)
headers['Accept-Ranges'] = 'bytes'
headers['Content-Length'] = str(stats.st_size)
if request.method != 'HEAD':
try:
_range = ContentRangeHandler(request, stats)
except HeaderNotFound:
pass
else:
del headers['Content-Length']
for key, value in _range.headers.items():
headers[key] = value
if request.method == 'HEAD':
return HTTPResponse(
headers=headers,
content_type=guess_type(file_path)[0] or 'text/plain')
else:
if stream_large_files:
if isinstance(stream_large_files, int):
threshold = stream_large_files
else:
threshold = 1024*1000
if not stats:
stats = await stat(file_path)
if stats.st_size >= threshold:
return await file_stream(file_path, headers=headers,
_range=_range)
return await file(file_path, headers=headers, _range=_range)
except ContentRangeError:
raise
except Exception:
raise FileNotFound('File not found',
path=file_or_directory,
relative_url=file_uri)
# special prefix for static files
if not name.startswith('_static_'):
name = '_static_{}'.format(name)
app.route(uri, methods=['GET', 'HEAD'], name=name, host=host)(_handler)