from __future__ import generators
"""
httplib2
A caching http interface that supports ETags and gzip
to conserve bandwidth.
Requires Python 2.3 or later
Changelog:
2007-08-18, Rick: Modified so it's able to use a socks proxy if needed.
"""
__author__ = "Joe Gregorio (joe@bitworking.org)"
__copyright__ = "Copyright 2006, Joe Gregorio"
__contributors__ = ["Thomas Broyer (t.broyer@ltgt.net)",
"James Antill",
"Xavier Verges Farrero",
"Jonathan Feinberg",
"Blair Zajac",
"Sam Ruby",
"Louis Nyffenegger"]
__license__ = "MIT"
__version__ = "$Rev: 259 $"
import re
import sys
from hashlib import md5
import email
import email.Utils
import email.Message
import StringIO
import gzip
import zlib
import httplib
import urlparse
import base64
import os
import copy
import calendar
import time
import random
from hashlib import sha1
import hmac
from gettext import gettext
import socket
import socks
if sys.version_info >= (2,3):
from iri2uri import iri2uri
else:
def iri2uri(uri):
return uri
__all__ = ['Http', 'Response', 'ProxyInfo', 'HttpLib2Error',
'RedirectMissingLocation', 'RedirectLimit', 'FailedToDecompressContent',
'UnimplementedDigestAuthOptionError', 'UnimplementedHmacDigestAuthOptionError',
'debuglevel']
# The httplib debug level, set to a non-zero value to get debug output
debuglevel = 0
# Python 2.3 support
if sys.version_info < (2,4):
def sorted(seq):
seq.sort()
return seq
# Python 2.3 support
def HTTPResponse__getheaders(self):
"""Return list of (header, value) tuples."""
if self.msg is None:
raise httplib.ResponseNotReady()
return self.msg.items()
if not hasattr(httplib.HTTPResponse, 'getheaders'):
httplib.HTTPResponse.getheaders = HTTPResponse__getheaders
# All exceptions raised here derive from HttpLib2Error
class HttpLib2Error(Exception): pass
# Some exceptions can be caught and optionally
# be turned back into responses.
class HttpLib2ErrorWithResponse(HttpLib2Error):
def __init__(self, desc, response, content):
self.response = response
self.content = content
HttpLib2Error.__init__(self, desc)
class RedirectMissingLocation(HttpLib2ErrorWithResponse): pass
class RedirectLimit(HttpLib2ErrorWithResponse): pass
class FailedToDecompressContent(HttpLib2ErrorWithResponse): pass
class UnimplementedDigestAuthOptionError(HttpLib2ErrorWithResponse): pass
class UnimplementedHmacDigestAuthOptionError(HttpLib2ErrorWithResponse): pass
class RelativeURIError(HttpLib2Error): pass
class ServerNotFoundError(HttpLib2Error): pass
# Open Items:
# -----------
# Proxy support
# Are we removing the cached content too soon on PUT (only delete on 200 Maybe?)
# Pluggable cache storage (supports storing the cache in
# flat files by default. We need a plug-in architecture
# that can support Berkeley DB and Squid)
# == Known Issues ==
# Does not handle a resource that uses conneg and Last-Modified but no ETag as a cache validator.
# Does not handle Cache-Control: max-stale
# Does not use Age: headers when calculating cache freshness.
# The number of redirections to follow before giving up.
# Note that only GET redirects are automatically followed.
# Will also honor 301 requests by saving that info and never
# requesting that URI again.
DEFAULT_MAX_REDIRECTS = 5
# Which headers are hop-by-hop headers by default
HOP_BY_HOP = ['connection', 'keep-alive', 'proxy-authenticate', 'proxy-authorization', 'te', 'trailers', 'transfer-encoding', 'upgrade']
def _get_end2end_headers(response):
hopbyhop = list(HOP_BY_HOP)
hopbyhop.extend([x.strip() for x in response.get('connection', '').split(',')])
return [header for header in response.keys() if header not in hopbyhop]
URI = re.compile(r"^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?")
def parse_uri(uri):
"""Parses a URI using the regex given in Appendix B of RFC 3986.
(scheme, authority, path, query, fragment) = parse_uri(uri)
"""
groups = URI.match(uri).groups()
return (groups[1], groups[3], groups[4], groups[6], groups[8])
def parse_proxy(uri):
"""
(scheme, user_name, password, authority, port, path, query, fragment) = parse_proxy(uri)
"""
groups=parse_uri(uri)
user_name=None
password=None
port=8080
proxy_type=None
if groups[0] in ["socks","tor"]:
port=9050
proxy_type=socks.PROXY_TYPE_SOCKS5
elif groups[0]=="socks4":
port=9050
proxy_type=socks.PROXY_TYPE_SOCKS4
elif groups[0]=="connect":
port=3128
proxy_type=socks.PROXY_TYPE_HTTP
server=groups[1]
if groups[1].find("@")>0:
creds,server=groups[1].split("@")
if creds.find(":")>0:
user_name,password=creds.split(":")
if server.find(":")>0:
server,s_port=server.split(":")
if s_port.isdigit():
port=int(s_port)
return (proxy_type,user_name,password,server,port,groups[2],groups[3],groups[4])
def urlnorm(uri):
(scheme, authority, path, query, fragment) = parse_uri(uri)
if not scheme or not authority:
raise RelativeURIError("Only absolute URIs are allowed. uri = %s" % uri)
authority = authority.lower()
scheme = scheme.lower()
if not path:
path = "/"
# Could do syntax based normalization of the URI before
# computing the digest. See Section 6.2.2 of Std 66.
request_uri = query and "?".join([path, query]) or path
scheme = scheme.lower()
defrag_uri = scheme + "://" + authority + request_uri
return scheme, authority, request_uri, defrag_uri
# Cache filename construction (original borrowed from Venus http://intertwingly.net/code/venus/)
re_url_scheme = re.compile(r'^\w+://')
re_slash = re.compile(r'[?/:|]+')
def safename(filename):
"""Return a filename suitable for the cache.
Strips dangerous and common characters to create a filename we
can use to store the cache in.
"""
try:
if re_url_scheme.match(filename):
if isinstance(filename,str):
filename = filename.decode('utf-8')
filename = filename.encode('idna')
else:
filename = filename.encode('idna')
except UnicodeError:
pass
if isinstance(filename,unicode):
filename=filename.encode('utf-8')
filemd5 = md5(filename).hexdigest()
filename = re_url_scheme.sub("", filename)
filename = re_slash.sub(",", filename)
# limit length of filename
if len(filename)>200:
filename=filename[:200]
return ",".join((filename, filemd5))
NORMALIZE_SPACE = re.compile(r'(?:\r\n)?[ \t]+')
def _normalize_headers(headers):
return dict([ (key.title(), NORMALIZE_SPACE.sub(value, ' ').strip()) for (key, value) in headers.iteritems()])
def _parse_cache_control(headers):
retval = {}
if headers.has_key('cache-control'):
parts = headers['cache-control'].split(',')
parts_with_args = [tuple([x.strip() for x in part.split("=")]) for part in parts if -1 != part.find("=")]
parts_wo_args = [(name.strip(), 1) for name in parts if -1 == name.find("=")]
retval = dict(parts_with_args + parts_wo_args)
return retval
# Whether to use a strict mode to parse WWW-Authenticate headers
# Might lead to bad results in case of ill-formed header value,
# so disabled by default, falling back to relaxed parsing.
# Set to true to turn on, usefull for testing servers.
USE_WWW_AUTH_STRICT_PARSING = 0
# In regex below:
# [^\0-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+ matches a "token" as defined by HTTP
# "(?:[^\0-\x08\x0A-\x1f\x7f-\xff\\\"]|\\[\0-\x7f])*?" matches a "quoted-string" as defined by HTTP, when LWS have already been replaced by a single space
# Actually, as an auth-param value can be either a token or a quoted-string, they are combined in a single pattern which matches both:
# \"?((?<=\")(?:[^\0-\x1f\x7f-\xff\\\"]|\\[\0-\x7f])*?(?=\")|(?<!\")[^\0-\x08\x0A-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+(?!\"))\"?
WWW_AUTH_STRICT = re.compile(r"^(?:\s*(?:,\s*)?([^\0-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+)\s*=\s*\"?((?<=\")(?:[^\0-\x08\x0A-\x1f\x7f-\xff\\\"]|\\[\0-\x7f])*?(?=\")|(?<!\")[^\0-\x1f\x7f-\xff()<>@,;:\\\"/[\]?={} \t]+(?!\"))\"?)(.*)$")
WWW_AUTH_RELAXED = re.compile(r"^(?:\s*(?:,\s*)?([^ \t\r\n=]+)\s*=\s*\"?((?<=\")(?:[^\\\"]|\\.)*?(?=\")|(?<!\")[^ \t\r\n,]+(?!\"))\"?)(.*)$")
UNQUOTE_PAIRS = re.compile(r'\\(.)')
def _parse_www_authenticate(headers, headername='www-authenticate'):
"""Returns a dictionary of dictionaries, one dict
per auth_scheme."""
retval = {}
if headers.has_key(headername):
authenticate = headers[headername].strip()
www_auth = USE_WWW_AUTH_STRICT_PARSING and WWW_AUTH_STRICT or WWW_AUTH_RELAXED
while authenticate:
# Break off the scheme at the beginning of the line
if headername == 'authentication-info':
(auth_scheme, the_rest) = ('digest', authenticate)
else:
(auth_scheme, the_rest) = authenticate.split(" ", 1)
# Now loop over all the key value pairs that come after the scheme,
# being careful not to roll into the next scheme
match = www_auth.search(the_rest)
auth_params = {}
while match:
if match and len(match.groups()) == 3:
(key, value, the_rest) = match.groups()
auth_params[key.lower()] = UNQUOTE_PAIRS.sub(r'\1', value) # '\\'.join([x.replace('\\', '') for x in value.split('\\\\')])
match = www_auth.search(the_rest)
retval[auth_scheme.lower()] = auth_params
authenticate = the_rest.strip()
return retval
def _entry_disposition(response_headers, request_headers):
"""Determine freshness from the Date, Expires and Cache-Control headers.
We don't handle the following:
1. Cache-Control: max-stale
2. Age: headers are not used in the calculations.
Not that this algorithm is simpler than you might think
because we are operating as a private (non-shared) cache.
This lets us ignore 's-maxage'. We can also ignore
'proxy-invalidate' since we aren't a proxy.
We will never return a stale document as
fresh as a design decision, and thus the non-implementation
of 'max-stale'. This also lets us safely ignore 'must-revalidate'
since we operate as if every server has sent 'must-revalidate'.
Since we are private we get to ignore both 'public' and
'private' parameters. We also ignore 'no-transform' since
we don't do any transformations.
The 'no-store' parameter is handled at a higher level.
So the only Cache-Control parameters we look at are:
no-cache
only-if-cached
max-age
min-fresh
"""
retval = "STALE"
cc = _parse_cache_control(request_headers)
cc_response = _parse_cache_control(response_headers)
if request_headers.has_key('pragma') and request_headers['pragma'].lower().find('no-cache') != -1:
retval = "TRANSPARENT"
if 'cache-control' not in request_headers:
request_headers['cache-control'] = 'no-cache'
elif cc.has_key('no-cache'):
retval = "TRANSPARENT"
elif cc_response.has_key('no-cache'):
retval = "STALE"
elif cc.has_key('only-if-cached'):
retval = "FRESH"
elif response_headers.has_key('date'):
date = calendar.timegm(email.Utils.parsedate_tz(response_headers['date']))
now = time.time()
current_age = max(0, now - date)
if cc_response.has_key('max-age'):
try:
freshness_lifetime = int(cc_response['max-age'])
except ValueError:
freshness_lifetime = 0
elif response_headers.has_key('expires'):
expires = email.Utils.parsedate_tz(response_headers['expires'])
if None == expires:
freshness_lifetime = 0
else:
freshness_lifetime = max(0, calendar.timegm(expires) - date)
else:
freshness_lifetime = 0
if cc.has_key('max-age'):
try:
freshness_lifetime = int(cc['max-age'])
except ValueError:
freshness_lifetime = 0
if cc.has_key('min-fresh'):
try:
min_fresh = int(cc['min-fresh'])
except ValueError:
min_fresh = 0
current_age += min_fresh
if freshness_lifetime > current_age:
retval = "FRESH"
return retval
def _decompressContent(response, new_content):
content = new_content
try:
encoding = response.get('content-encoding', None)
if encoding in ['gzip', 'deflate']:
if encoding == 'gzip':
content = gzip.GzipFile(fileobj=StringIO.StringIO(new_content)).read()
if encoding == 'deflate':
content = zlib.decompress(content)
response['content-length'] = str(len(content))
del response['content-encoding']
except IOError:
content = ""
raise FailedToDecompressContent(_("Content purported to be compressed with %s but failed to decompress.") % response.get('content-encoding'), response, content)
return content
def _updateCache(request_headers, response_headers, content, cache, cachekey):
if cachekey:
cc = _parse_cache_control(request_headers)
cc_response = _parse_cache_control(response_headers)
if cc.has_key('no-store') or cc_response.has_key('no-store'):
cache.delete(cachekey)
else:
info = email.Message.Message()
for key, value in response_headers.iteritems():
if key not in ['status','content-encoding','transfer-encoding']:
info[key] = value
status = response_headers.status
if status == 304:
status = 200
status_header = 'status: %d\r\n' % response_headers.status
header_str = info.as_string()
header_str = re.sub("\r(?!\n)|(?<!\r)\n", "\r\n", header_str)
text = "".join([status_header, header_str, content])
cache.set(cachekey, text)
def _cnonce():
dig = md5("%s:%s" % (time.ctime(), ["0123456789"[random.randrange(0, 9)] for i in range(20)])).hexdigest()
return dig[:16]
def _wsse_username_token(cnonce, iso_now, password):
return base64.encodestring(sha("%s%s%s" % (cnonce, iso_now, password)).digest()).strip()
# For credentials we need two things, first
# a pool of credential to try (not necesarily tied to BAsic, Digest, etc.)
# Then we also need a list of URIs that have already demanded authentication
# That list is tricky since sub-URIs can take the same auth, or the
# auth scheme may change as you descend the tree.
# So we also need each Auth instance to be able to tell us
# how close to the 'top' it is.
class Authentication(object):
def __init__(self, credentials, host, request_uri, headers, response, content, http):
(scheme, authority, path, query, fragment) = parse_uri(request_uri)
self.path = path
self.host = host
self.credentials = credentials
self.http = http
def depth(self, request_uri):
(scheme, authority, path, query, fragment) = parse_uri(request_uri)
return request_uri[len(self.path):].count("/")
def inscope(self, host, request_uri):
# XXX Should we normalize the request_uri?
(scheme, authority, path, query, fragment) = parse_uri(request_uri)
return (host == self.host) and path.startswith(self.path)
def request(self, method, request_uri, headers, content):
"""Modify the request headers to add the appropriate
Authorization header. Over-rise this in sub-classes."""
pass
def response(self, response, content):
"""Gives us a chance to update with new nonces
or such returned from the last authorized response.
Over-rise this in sub-classes if necessary.
Return TRUE is the request is to be retried, for
example Digest may return stale=true.
"""
return False
class BasicAuthentication(Authentication):
def __init__(self, credentials, host, request_uri, headers, response, content, http):
Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http)
def request(self, method, request_uri, headers, content):
"""Modify the request headers to add the appropriate
Authorization header."""
headers['authorization'] = 'Basic ' + base64.encodestring("%s:%s" % self.credentials).strip()
class DigestAuthentication(Authentication):
"""Only do qop='auth' and MD5, since that
is all Apache currently implements"""
def __init__(self, credentials, host, request_uri, headers, response, content, http):
Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http)
challenge = _parse_www_authenticate(response, 'www-authenticate')
self.challenge = challenge['digest']
qop = self.challenge.get('qop')
self.challenge['qop'] = ('auth' in [x.strip() for x in qop.split()]) and 'auth' or None
if self.challenge['qop'] is None:
raise UnimplementedDigestAuthOptionError( _("Unsupported value for qop: %s." % qop))
self.challenge['algorithm'] = self.challenge.get('algorithm', 'MD5')
if self.challenge['algorithm'] != 'MD5':
raise UnimplementedDigestAuthOptionError( _("Unsupported value for algorithm: %s." % self.challenge['algorithm']))
self.A1 = "".join([self.credentials[0], ":", self.challenge['realm'], ":", self.credentials[1]])
self.challenge['nc'] = 1
def request(self, method, request_uri, headers, content, cnonce = None):
"""Modify the request headers"""
H = lambda x: md5(x).hexdigest()
KD = lambda s, d: H("%s:%s" % (s, d))
A2 = "".join([method, ":", request_uri])
self.challenge['cnonce'] = cnonce or _cnonce()
request_digest = '"%s"' % KD(H(self.A1), "%s:%s:%s:%s:%s" % (self.challenge['nonce'],
'%08x' % self.challenge['nc'],
self.challenge['cnonce'],
self.challenge['qop'], H(A2)
))
headers['Authorization'] = 'Digest username="%s", realm="%s", nonce="%s", uri="%s", algorithm=%s, response=%s, qop=%s, nc=%08x, cnonce="%s"' % (
self.credentials[0],
self.challenge['realm'],
self.challenge['nonce'],
request_uri,
self.challenge['algorithm'],
request_digest,
self.challenge['qop'],
self.challenge['nc'],
self.challenge['cnonce'],
)
self.challenge['nc'] += 1
def response(self, response, content):
if not response.has_key('authentication-info'):
challenge = _parse_www_authenticate(response, 'www-authenticate').get('digest', {})
if 'true' == challenge.get('stale'):
self.challenge['nonce'] = challenge['nonce']
self.challenge['nc'] = 1
return True
else:
updated_challenge = _parse_www_authenticate(response, 'authentication-info').get('digest', {})
if updated_challenge.has_key('nextnonce'):
self.challenge['nonce'] = updated_challenge['nextnonce']
self.challenge['nc'] = 1
return False
class HmacDigestAuthentication(Authentication):
"""Adapted from Robert Sayre's code and DigestAuthentication above."""
__author__ = "Thomas Broyer (t.broyer@ltgt.net)"
def __init__(self, credentials, host, request_uri, headers, response, content, http):
Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http)
challenge = _parse_www_authenticate(response, 'www-authenticate')
self.challenge = challenge['hmacdigest']
# TODO: self.challenge['domain']
self.challenge['reason'] = self.challenge.get('reason', 'unauthorized')
if self.challenge['reason'] not in ['unauthorized', 'integrity']:
self.challenge['reason'] = 'unauthorized'
self.challenge['salt'] = self.challenge.get('salt', '')
if not self.challenge.get('snonce'):
raise UnimplementedHmacDigestAuthOptionError( _("The challenge doesn't contain a server nonce, or this one is empty."))
self.challenge['algorithm'] = self.challenge.get('algorithm', 'HMAC-SHA-1')
if self.challenge['algorithm'] not in ['HMAC-SHA-1', 'HMAC-MD5']:
raise UnimplementedHmacDigestAuthOptionError( _("Unsupported value for algorithm: %s." % self.challenge['algorithm']))
self.challenge['pw-algorithm'] = self.challenge.get('pw-algorithm', 'SHA-1')
if self.challenge['pw-algorithm'] not in ['SHA-1', 'MD5']:
raise UnimplementedHmacDigestAuthOptionError( _("Unsupported value for pw-algorithm: %s." % self.challenge['pw-algorithm']))
if self.challenge['algorithm'] == 'HMAC-MD5':
self.hashmod = md5
else:
self.hashmod = sha
if self.challenge['pw-algorithm'] == 'MD5':
self.pwhashmod = md5
else:
self.pwhashmod = sha
self.key = "".join([self.credentials[0], ":",
self.pwhashmod.new("".join([self.credentials[1], self.challenge['salt']])).hexdigest().lower(),
":", self.challenge['realm']
])
self.key = self.pwhashmod.new(self.key).hexdigest().lower()
def request(self, method, request_uri, headers, content):
"""Modify the request headers"""
keys = _get_end2end_headers(headers)
keylist = "".join(["%s " % k for k in keys])
headers_val = "".join([headers[k] for k in keys])
created = time.strftime('%Y-%m-%dT%H:%M:%SZ',time.gmtime())
cnonce = _cnonce()
request_digest = "%s:%s:%s:%s:%s" % (method, request_uri, cnonce, self.challenge['snonce'], headers_val)
request_digest = hmac.new(self.key, request_digest, self.hashmod).hexdigest().lower()
headers['Authorization'] = 'HMACDigest username="%s", realm="%s", snonce="%s", cnonce="%s", uri="%s", created="%s", response="%s", headers="%s"' % (
self.credentials[0],
self.challenge['realm'],
self.challenge['snonce'],
cnonce,
request_uri,
created,
request_digest,
keylist,
)
def response(self, response, content):
challenge = _parse_www_authenticate(response, 'www-authenticate').get('hmacdigest', {})
if challenge.get('reason') in ['integrity', 'stale']:
return True
return False
class WsseAuthentication(Authentication):
"""This is thinly tested and should not be relied upon.
At this time there isn't any third party server to test against.
Blogger and TypePad implemented this algorithm at one point
but Blogger has since switched to Basic over HTTPS and
TypePad has implemented it wrong, by never issuing a 401
challenge but instead requiring your client to telepathically know that
their endpoint is expecting WSSE profile="UsernameToken"."""
def __init__(self, credentials, host, request_uri, headers, response, content, http):
Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http)
def request(self, method, request_uri, headers, content):
"""Modify the request headers to add the appropriate
Authorization header."""
headers['Authorization'] = 'WSSE profile="UsernameToken"'
iso_now = time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime())
cnonce = _cnonce()
password_digest = _wsse_username_token(cnonce, iso_now, self.credentials[1])
headers['X-WSSE'] = 'UsernameToken Username="%s", PasswordDigest="%s", Nonce="%s", Created="%s"' % (
self.credentials[0],
password_digest,
cnonce,
iso_now)
class GoogleLoginAuthentication(Authentication):
def __init__(self, credentials, host, request_uri, headers, response, content, http):
from urllib import urlencode
Authentication.__init__(self, credentials, host, request_uri, headers, response, content, http)
challenge = _parse_www_authenticate(response, 'www-authenticate')
service = challenge['googlelogin'].get('service', 'xapi')
# Bloggger actually returns the service in the challenge
# For the rest we guess based on the URI
if service == 'xapi' and request_uri.find("calendar") > 0:
service = "cl"
# No point in guessing Base or Spreadsheet
#elif request_uri.find("spreadsheets") > 0:
# service = "wise"
auth = dict(Email=credentials[0], Passwd=credentials[1], service=service, source=headers['User-Agent'])
resp, content = self.http.request("https://www.google.com/accounts/ClientLogin", method="POST", body=urlencode(auth), headers={'Content-Type': 'application/x-www-form-urlencoded'})
lines = content.split('\n')
d = dict([tuple(line.split("=", 1)) for line in lines if line])
if resp.status == 403:
self.Auth = ""
else:
self.Auth = d['Auth']
def request(self, method, request_uri, headers, content):
"""Modify the request headers to add the appropriate
Authorization header."""
headers['authorization'] = 'GoogleLogin Auth=' + self.Auth
AUTH_SCHEME_CLASSES = {
"basic": BasicAuthentication,
"wsse": WsseAuthentication,
"digest": DigestAuthentication,
"hmacdigest": HmacDigestAuthentication,
"googlelogin": GoogleLoginAuthentication
}
AUTH_SCHEME_ORDER = ["hmacdigest", "googlelogin", "digest", "wsse", "basic"]
def _md5(s):
return
class FileCache(object):
"""Uses a local directory as a store for cached files.
Not really safe to use if multiple threads or processes are going to
be running on the same cache.
"""
def __init__(self, cache, safe=safename): # use safe=lambda x: md5.new(x).hexdigest() for the old behavior
self.cache = cache
self.safe = safe
if not os.path.exists(cache):
os.makedirs(self.cache)
def get(self, key):
retval = None
cacheFullPath = os.path.join(self.cache, self.safe(key))
try:
f = file(cacheFullPath, "r")
retval = f.read()
f.close()
except IOError:
pass
return retval
def set(self, key, value):
cacheFullPath = os.path.join(self.cache, self.safe(key))
f = file(cacheFullPath, "w")
f.write(value)
f.close()
def delete(self, key):
cacheFullPath = os.path.join(self.cache, self.safe(key))
if os.path.exists(cacheFullPath):
os.remove(cacheFullPath)
class Credentials(object):
def __init__(self):
self.credentials = []
def add(self, name, password, domain=""):
self.credentials.append((domain.lower(), name, password))
def clear(self):
self.credentials = []
def iter(self, domain):
for (cdomain, name, password) in self.credentials:
if cdomain == "" or domain == cdomain:
yield (name, password)
class KeyCerts(Credentials):
"""Identical to Credentials except that
name/password are mapped to key/cert."""
pass
class ProxyInfo(object):
"""Collect information required to use a proxy."""
def __init__(self, proxy_type, proxy_host, proxy_port, proxy_rdns=None, proxy_user=None, proxy_pass=None):
"""The parameter proxy_type must be set to one of socks.PROXY_TYPE_XXX
constants. For example:
p = ProxyInfo(proxy_type=socks.PROXY_TYPE_HTTP, proxy_host='localhost', proxy_port=8000)
"""
self.proxy_type, self.proxy_host, self.proxy_port, self.proxy_rdns, self.proxy_user, self.proxy_pass = proxy_type, proxy_host, proxy_port, proxy_rdns, proxy_user, proxy_pass
def astuple(self):
return (self.proxy_type, self.proxy_host, self.proxy_port, self.proxy_rdns,
self.proxy_user, self.proxy_pass)
def isgood(self):
return socks and (self.proxy_host != None) and (self.proxy_port != None)
class HTTPConnectionWithTimeout(httplib.HTTPConnection):
"""HTTPConnection subclass that supports timeouts"""
def __init__(self, host, port=None, strict=None, timeout=None, proxy_info=None):
httplib.HTTPConnection.__init__(self, host, port, strict)
self.timeout = timeout
self.proxy_info = proxy_info
def connect(self):
"""Connect to the host and port specified in __init__."""
# Mostly verbatim from httplib.py.
msg = "getaddrinfo returns an empty list"
for res in socket.getaddrinfo(self.host, self.port, 0, socket.SOCK_STREAM):
af, socktype, proto, canonname, sa = res
try:
if self.proxy_info and self.proxy_info.isgood():
self.sock = socks.socksocket(af, socktype, proto)
self.sock.setproxy(*self.proxy_info.astuple())
else:
self.sock = socket.socket(af, socktype, proto)
# Different from httplib: support timeouts.
if self.timeout is not None:
self.sock.settimeout(float(self.timeout))
# End of difference from httplib.
if self.debuglevel > 0:
print "connect: (%s, %s)" % (self.host, self.port)
self.sock.connect(sa)
except socket.error, msg:
if self.debuglevel > 0:
print 'connect fail:', (self.host, self.port)
if self.sock:
self.sock.close()
self.sock = None
continue
break
if not self.sock:
raise socket.error, msg
class HTTPSConnectionWithTimeout(httplib.HTTPSConnection):
"This class allows communication via SSL."
def __init__(self, host, port=None, key_file=None, cert_file=None,
strict=None, timeout=None, proxy_info=None):
self.timeout = timeout
self.proxy_info = proxy_info
httplib.HTTPSConnection.__init__(self, host, port=port, key_file=key_file,
cert_file=cert_file, strict=strict)
def connect(self):
"Connect to a host on a given (SSL) port."
if self.proxy_info and self.proxy_info.isgood():
self.sock.setproxy(*self.proxy_info.astuple())
sock.setproxy(*self.proxy_info.astuple())
else:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
if self.timeout is not None:
sock.settimeout(float(self.timeout))
sock.connect((self.host, self.port))
ssl = socket.ssl(sock, self.key_file, self.cert_file)
self.sock = httplib.FakeSocket(sock, ssl)
class Http(object):
"""An HTTP client that handles:
- all methods
- caching
- ETags
- compression,
- HTTPS
- Basic
- Digest
- WSSE
and more.
"""
def __init__(self, cache=None, timeout=None, proxy_info=None):
"""The value of proxy_info is a ProxyInfo instance.
If 'cache' is a string then it is used as a directory name
for a disk cache. Otherwise it must be an object that supports
the same interface as FileCache."""
self.proxy_info = proxy_info
# Map domain name to an httplib connection
self.connections = {}
# The location of the cache, for now a directory
# where cached responses are held.
if cache and isinstance(cache, str):
self.cache = FileCache(cache)
else:
self.cache = cache
# Name/password
self.credentials = Credentials()
# Key/cert
self.certificates = KeyCerts()
# authorization objects
self.authorizations = []
# If set to False then no redirects are followed, even safe ones.
self.follow_redirects = True
# If 'follow_redirects' is True, and this is set to True then
# all redirecs are followed, including unsafe ones.
self.follow_all_redirects = False
self.ignore_etag = False
self.force_exception_to_status_code = False
self.timeout = timeout
def _auth_from_challenge(self, host, request_uri, headers, response, content):
"""A generator that creates Authorization objects
that can be applied to requests.
"""
challenges = _parse_www_authenticate(response, 'www-authenticate')
for cred in self.credentials.iter(host):
for scheme in AUTH_SCHEME_ORDER:
if challenges.has_key(scheme):
yield AUTH_SCHEME_CLASSES[scheme](cred, host, request_uri, headers, response, content, self)
def add_credentials(self, name, password, domain=""):
"""Add a name and password that will be used
any time a request requires authentication."""
self.credentials.add(name, password, domain)
def add_certificate(self, key, cert, domain):
"""Add a key and cert that will be used
any time a request requires authentication."""
self.certificates.add(key, cert, domain)
def clear_credentials(self):
"""Remove all the names and passwords
that are used for authentication"""
self.credentials.clear()
self.authorizations = []
def _conn_request(self, conn, request_uri, method, body, headers):
for i in range(2):
try:
conn.request(method, request_uri, body, headers)
response = conn.getresponse()
except socket.gaierror:
conn.close()
raise ServerNotFoundError("Unable to find the server at %s" % conn.host)
except httplib.HTTPException, e:
if i == 0:
conn.close()
conn.connect()
continue
else:
raise
else:
content = response.read()
response = Response(response)
if method != "HEAD":
content = _decompressContent(response, content)
break;
return (response, content)
def _request(self, conn, host, absolute_uri, request_uri, method, body, headers, redirections, cachekey):
"""Do the actual request using the connection object
and also follow one level of redirects if necessary"""
auths = [(auth.depth(request_uri), auth) for auth in self.authorizations if auth.inscope(host, request_uri)]
auth = auths and sorted(auths)[0][1] or None
if auth:
auth.request(method, request_uri, headers, body)
## if we use simple HTTP proxies, use absolute urls
if self.proxy_info!=None and self.proxy_info.proxy_type==None:
#headers["Proxy-Connection"]="Keep-Alive"
(response, content) = self._conn_request(conn, absolute_uri, method, body, headers)
else:
(response, content) = self._conn_request(conn, request_uri, method, body, headers)
if auth:
if auth.response(response, body):
auth.request(method, request_uri, headers, body)
(response, content) = self._conn_request(conn, request_uri, method, body, headers )
response._stale_digest = 1
if response.status == 401:
for authorization in self._auth_from_challenge(host, request_uri, headers, response, content):
authorization.request(method, request_uri, headers, body)
(response, content) = self._conn_request(conn, request_uri, method, body, headers, )
if response.status != 401:
self.authorizations.append(authorization)
authorization.response(response, body)
break
if (self.follow_all_redirects or (method in ["GET", "HEAD"]) or response.status == 303):
if self.follow_redirects and response.status in [300, 301, 302, 303, 307]:
# Pick out the location header and basically start from the beginning
# remembering first to strip the ETag header and decrement our 'depth'
if redirections:
if not response.has_key('location') and response.status != 300:
raise RedirectMissingLocation( _("Redirected but the response is missing a Location: header."), response, content)
# Fix-up relative redirects (which violate an RFC 2616 MUST)
if response.has_key('location'):
location = response['location']
(scheme, authority, path, query, fragment) = parse_uri(location)
if authority == None:
response['location'] = urlparse.urljoin(absolute_uri, location)
if response.status == 301 and method in ["GET", "HEAD"]:
response['-x-permanent-redirect-url'] = response['location']
if not response.has_key('content-location'):
response['content-location'] = absolute_uri
_updateCache(headers, response, content, self.cache, cachekey)
if headers.has_key('if-none-match'):
del headers['if-none-match']
if headers.has_key('if-modified-since'):
del headers['if-modified-since']
if response.has_key('location'):
location = response['location']
old_response = copy.deepcopy(response)
if not old_response.has_key('content-location'):
old_response['content-location'] = absolute_uri
redirect_method = ((response.status == 303) and (method not in ["GET", "HEAD"])) and "GET" or method
(response, content) = self.request(location, redirect_method, body=body, headers = headers, redirections = redirections - 1)
response.previous = old_response
else:
raise RedirectLimit( _("Redirected more times than rediection_limit allows."), response, content)
elif response.status in [200, 203] and method == "GET":
# Don't cache 206's since we aren't going to handle byte range requests
if not response.has_key('content-location'):
response['content-location'] = absolute_uri
_updateCache(headers, response, content, self.cache, cachekey)
return (response, content)
# Need to catch and rebrand some exceptions
# Then need to optionally turn all exceptions into status codes
# including all socket.* and httplib.* exceptions.
def request(self, uri, method="GET", body=None, headers=None, redirections=DEFAULT_MAX_REDIRECTS, connection_type=None):
""" Performs a single HTTP request.
The 'uri' is the URI of the HTTP resource and can begin
with either 'http' or 'https'. The value of 'uri' must be an absolute URI.
The 'method' is the HTTP method to perform, such as GET, POST, DELETE, etc.
There is no restriction on the methods allowed.
The 'body' is the entity body to be sent with the request. It is a string
object.
Any extra headers that are to be sent with the request should be provided in the
'headers' dictionary.
The maximum number of redirect to follow before raising an
exception is 'redirections. The default is 5.
The return value is a tuple of (response, content), the first
being and instance of the 'Response' class, the second being
a string that contains the response entity body.
"""
try:
if headers is None:
headers = {}
else:
headers = _normalize_headers(headers)
if not headers.has_key('User-Agent'):
headers['User-Agent'] = "Python-httplib2/%s" % __version__
uri = iri2uri(uri)
(scheme, authority, request_uri, defrag_uri) = urlnorm(uri)
conn_key = scheme+":"+authority
if conn_key in self.connections:
conn = self.connections[conn_key]
else:
if not connection_type:
connection_type = (scheme == 'https') and HTTPSConnectionWithTimeout or HTTPConnectionWithTimeout
certs = list(self.certificates.iter(authority))
if scheme == 'https' and certs:
conn = self.connections[conn_key] = connection_type(authority, key_file=certs[0][0],
cert_file=certs[0][1], timeout=self.timeout, proxy_info=self.proxy_info)
else:
conn = self.connections[conn_key] = connection_type(authority, timeout=self.timeout, proxy_info=self.proxy_info)
conn.set_debuglevel(debuglevel)
if method in ["GET", "HEAD"] and 'range' not in headers:
headers['Accept-Encoding'] = 'compress, gzip'
info = email.Message.Message()
cached_value = None
if self.cache:
cachekey = defrag_uri
cached_value = self.cache.get(cachekey)
if cached_value:
info = email.message_from_string(cached_value)
try:
content = cached_value.split('\r\n\r\n', 1)[1]
except IndexError:
self.cache.delete(cachekey)
cachekey = None
cached_value = None
else:
cachekey = None
if method in ["PUT"] and self.cache and info.has_key('etag') and not self.ignore_etag and 'if-match' not in headers:
# http://www.w3.org/1999/04/Editing/
headers['if-match'] = info['etag']
if method not in ["GET", "HEAD"] and self.cache and cachekey:
# RFC 2616 Section 13.10
self.cache.delete(cachekey)
if cached_value and method in ["GET", "HEAD"] and self.cache and 'range' not in headers:
if info.has_key('-x-permanent-redirect-url'):
# Should cached permanent redirects be counted in our redirection count? For now, yes.
(response, new_content) = self.request(info['-x-permanent-redirect-url'], "GET", headers = headers, redirections = redirections - 1)
response.previous = Response(info)
response.previous.fromcache = True
else:
# Determine our course of action:
# Is the cached entry fresh or stale?
# Has the client requested a non-cached response?
#
# There seems to be three possible answers:
# 1. [FRESH] Return the cache entry w/o doing a GET
# 2. [STALE] Do the GET (but add in cache validators if available)
# 3. [TRANSPARENT] Do a GET w/o any cache validators (Cache-Control: no-cache) on the request
entry_disposition = _entry_disposition(info, headers)
if entry_disposition == "FRESH":
if not cached_value:
info['status'] = '504'
content = ""
response = Response(info)
if cached_value:
response.fromcache = True
return (response, content)
if entry_disposition == "STALE":
if info.has_key('etag') and not self.ignore_etag and not 'if-none-match' in headers:
headers['if-none-match'] = info['etag']
if info.has_key('last-modified') and not 'last-modified' in headers:
headers['if-modified-since'] = info['last-modified']
elif entry_disposition == "TRANSPARENT":
pass
(response, new_content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
if response.status == 304 and method == "GET":
# Rewrite the cache entry with the new end-to-end headers
# Take all headers that are in response
# and overwrite their values in info.
# unless they are hop-by-hop, or are listed in the connection header.
for key in _get_end2end_headers(response):
info[key] = response[key]
merged_response = Response(info)
if hasattr(response, "_stale_digest"):
merged_response._stale_digest = response._stale_digest
_updateCache(headers, merged_response, content, self.cache, cachekey)
response = merged_response
response.status = 200
response.fromcache = True
elif response.status == 200:
content = new_content
else:
self.cache.delete(cachekey)
content = new_content
else:
(response, content) = self._request(conn, authority, uri, request_uri, method, body, headers, redirections, cachekey)
except Exception, e:
if self.force_exception_to_status_code:
if isinstance(e, HttpLib2ErrorWithResponse):
response = e.response
content = e.content
response.status = 500
response.reason = str(e)
elif isinstance(e, socket.timeout):
content = "Request Timeout"
response = Response( {
"content-type": "text/plain",
"status": "408",
"content-length": len(content)
})
response.reason = "Request Timeout"
else:
content = str(e)
response = Response( {
"content-type": "text/plain",
"status": "400",
"content-length": len(content)
})
response.reason = "Bad Request"
else:
raise
return (response, content)
class Response(dict):
"""An object more like email.Message than httplib.HTTPResponse."""
"""Is this response from our local cache"""
fromcache = False
"""HTTP protocol version used by server. 10 for HTTP/1.0, 11 for HTTP/1.1. """
version = 11
"Status code returned by server. "
status = 200
"""Reason phrase returned by server."""
reason = "Ok"
previous = None
def __init__(self, info):
# info is either an email.Message or
# an httplib.HTTPResponse object.
if isinstance(info, httplib.HTTPResponse):
for key, value in info.getheaders():
self[key] = value
self.status = info.status
self['status'] = str(self.status)
self.reason = info.reason
self.version = info.version
elif isinstance(info, email.Message.Message):
for key, value in info.items():
self[key] = value
self.status = int(self['status'])
else:
for key, value in info.iteritems():
self[key] = value
self.status = int(self.get('status', self.status))
def __getattr__(self, name):
if name == 'dict':
return self
else:
raise AttributeError, name
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