ref: 375d8f437013d0d5106e6c8c6d8dd79db6de456a
dir: /sys/lib/python/urllib.py/
"""Open an arbitrary URL.
See the following document for more info on URLs:
"Names and Addresses, URIs, URLs, URNs, URCs", at
http://www.w3.org/pub/WWW/Addressing/Overview.html
See also the HTTP spec (from which the error codes are derived):
"HTTP - Hypertext Transfer Protocol", at
http://www.w3.org/pub/WWW/Protocols/
Related standards and specs:
- RFC1808: the "relative URL" spec. (authoritative status)
- RFC1738 - the "URL standard". (authoritative status)
- RFC1630 - the "URI spec". (informational status)
The object returned by URLopener().open(file) will differ per
protocol. All you know is that is has methods read(), readline(),
readlines(), fileno(), close() and info(). The read*(), fileno()
and close() methods work like those of open files.
The info() method returns a mimetools.Message object which can be
used to query various info about the object, if available.
(mimetools.Message objects are queried with the getheader() method.)
"""
import string
import socket
import os
import time
import sys
from urlparse import urljoin as basejoin
__all__ = ["urlopen", "URLopener", "FancyURLopener", "urlretrieve",
"urlcleanup", "quote", "quote_plus", "unquote", "unquote_plus",
"urlencode", "url2pathname", "pathname2url", "splittag",
"localhost", "thishost", "ftperrors", "basejoin", "unwrap",
"splittype", "splithost", "splituser", "splitpasswd", "splitport",
"splitnport", "splitquery", "splitattr", "splitvalue",
"splitgophertype", "getproxies"]
__version__ = '1.17' # XXX This version is not always updated :-(
MAXFTPCACHE = 10 # Trim the ftp cache beyond this size
# Helper for non-unix systems
if os.name == 'mac':
from macurl2path import url2pathname, pathname2url
elif os.name == 'nt':
from nturl2path import url2pathname, pathname2url
elif os.name == 'riscos':
from rourl2path import url2pathname, pathname2url
else:
def url2pathname(pathname):
"""OS-specific conversion from a relative URL of the 'file' scheme
to a file system path; not recommended for general use."""
return unquote(pathname)
def pathname2url(pathname):
"""OS-specific conversion from a file system path to a relative URL
of the 'file' scheme; not recommended for general use."""
return quote(pathname)
# This really consists of two pieces:
# (1) a class which handles opening of all sorts of URLs
# (plus assorted utilities etc.)
# (2) a set of functions for parsing URLs
# XXX Should these be separated out into different modules?
# Shortcut for basic usage
_urlopener = None
def urlopen(url, data=None, proxies=None):
"""urlopen(url [, data]) -> open file-like object"""
global _urlopener
if proxies is not None:
opener = FancyURLopener(proxies=proxies)
elif not _urlopener:
opener = FancyURLopener()
_urlopener = opener
else:
opener = _urlopener
if data is None:
return opener.open(url)
else:
return opener.open(url, data)
def urlretrieve(url, filename=None, reporthook=None, data=None):
global _urlopener
if not _urlopener:
_urlopener = FancyURLopener()
return _urlopener.retrieve(url, filename, reporthook, data)
def urlcleanup():
if _urlopener:
_urlopener.cleanup()
# exception raised when downloaded size does not match content-length
class ContentTooShortError(IOError):
def __init__(self, message, content):
IOError.__init__(self, message)
self.content = content
ftpcache = {}
class URLopener:
"""Class to open URLs.
This is a class rather than just a subroutine because we may need
more than one set of global protocol-specific options.
Note -- this is a base class for those who don't want the
automatic handling of errors type 302 (relocated) and 401
(authorization needed)."""
__tempfiles = None
version = "Python-urllib/%s" % __version__
# Constructor
def __init__(self, proxies=None, **x509):
if proxies is None:
proxies = getproxies()
assert hasattr(proxies, 'has_key'), "proxies must be a mapping"
self.proxies = proxies
self.key_file = x509.get('key_file')
self.cert_file = x509.get('cert_file')
self.addheaders = [('User-Agent', self.version)]
self.__tempfiles = []
self.__unlink = os.unlink # See cleanup()
self.tempcache = None
# Undocumented feature: if you assign {} to tempcache,
# it is used to cache files retrieved with
# self.retrieve(). This is not enabled by default
# since it does not work for changing documents (and I
# haven't got the logic to check expiration headers
# yet).
self.ftpcache = ftpcache
# Undocumented feature: you can use a different
# ftp cache by assigning to the .ftpcache member;
# in case you want logically independent URL openers
# XXX This is not threadsafe. Bah.
def __del__(self):
self.close()
def close(self):
self.cleanup()
def cleanup(self):
# This code sometimes runs when the rest of this module
# has already been deleted, so it can't use any globals
# or import anything.
if self.__tempfiles:
for file in self.__tempfiles:
try:
self.__unlink(file)
except OSError:
pass
del self.__tempfiles[:]
if self.tempcache:
self.tempcache.clear()
def addheader(self, *args):
"""Add a header to be used by the HTTP interface only
e.g. u.addheader('Accept', 'sound/basic')"""
self.addheaders.append(args)
# External interface
def open(self, fullurl, data=None):
"""Use URLopener().open(file) instead of open(file, 'r')."""
fullurl = unwrap(toBytes(fullurl))
if self.tempcache and fullurl in self.tempcache:
filename, headers = self.tempcache[fullurl]
fp = open(filename, 'rb')
return addinfourl(fp, headers, fullurl)
urltype, url = splittype(fullurl)
if not urltype:
urltype = 'file'
if urltype in self.proxies:
proxy = self.proxies[urltype]
urltype, proxyhost = splittype(proxy)
host, selector = splithost(proxyhost)
url = (host, fullurl) # Signal special case to open_*()
else:
proxy = None
name = 'open_' + urltype
self.type = urltype
name = name.replace('-', '_')
if not hasattr(self, name):
if proxy:
return self.open_unknown_proxy(proxy, fullurl, data)
else:
return self.open_unknown(fullurl, data)
try:
if data is None:
return getattr(self, name)(url)
else:
return getattr(self, name)(url, data)
except socket.error, msg:
raise IOError, ('socket error', msg), sys.exc_info()[2]
def open_unknown(self, fullurl, data=None):
"""Overridable interface to open unknown URL type."""
type, url = splittype(fullurl)
raise IOError, ('url error', 'unknown url type', type)
def open_unknown_proxy(self, proxy, fullurl, data=None):
"""Overridable interface to open unknown URL type."""
type, url = splittype(fullurl)
raise IOError, ('url error', 'invalid proxy for %s' % type, proxy)
# External interface
def retrieve(self, url, filename=None, reporthook=None, data=None):
"""retrieve(url) returns (filename, headers) for a local object
or (tempfilename, headers) for a remote object."""
url = unwrap(toBytes(url))
if self.tempcache and url in self.tempcache:
return self.tempcache[url]
type, url1 = splittype(url)
if filename is None and (not type or type == 'file'):
try:
fp = self.open_local_file(url1)
hdrs = fp.info()
del fp
return url2pathname(splithost(url1)[1]), hdrs
except IOError, msg:
pass
fp = self.open(url, data)
headers = fp.info()
if filename:
tfp = open(filename, 'wb')
else:
import tempfile
garbage, path = splittype(url)
garbage, path = splithost(path or "")
path, garbage = splitquery(path or "")
path, garbage = splitattr(path or "")
suffix = os.path.splitext(path)[1]
(fd, filename) = tempfile.mkstemp(suffix)
self.__tempfiles.append(filename)
tfp = os.fdopen(fd, 'wb')
result = filename, headers
if self.tempcache is not None:
self.tempcache[url] = result
bs = 1024*8
size = -1
read = 0
blocknum = 0
if reporthook:
if "content-length" in headers:
size = int(headers["Content-Length"])
reporthook(blocknum, bs, size)
while 1:
block = fp.read(bs)
if block == "":
break
read += len(block)
tfp.write(block)
blocknum += 1
if reporthook:
reporthook(blocknum, bs, size)
fp.close()
tfp.close()
del fp
del tfp
# raise exception if actual size does not match content-length header
if size >= 0 and read < size:
raise ContentTooShortError("retrieval incomplete: got only %i out "
"of %i bytes" % (read, size), result)
return result
# Each method named open_<type> knows how to open that type of URL
def open_http(self, url, data=None):
"""Use HTTP protocol."""
import httplib
user_passwd = None
proxy_passwd= None
if isinstance(url, str):
host, selector = splithost(url)
if host:
user_passwd, host = splituser(host)
host = unquote(host)
realhost = host
else:
host, selector = url
# check whether the proxy contains authorization information
proxy_passwd, host = splituser(host)
# now we proceed with the url we want to obtain
urltype, rest = splittype(selector)
url = rest
user_passwd = None
if urltype.lower() != 'http':
realhost = None
else:
realhost, rest = splithost(rest)
if realhost:
user_passwd, realhost = splituser(realhost)
if user_passwd:
selector = "%s://%s%s" % (urltype, realhost, rest)
if proxy_bypass(realhost):
host = realhost
#print "proxy via http:", host, selector
if not host: raise IOError, ('http error', 'no host given')
if proxy_passwd:
import base64
proxy_auth = base64.b64encode(proxy_passwd).strip()
else:
proxy_auth = None
if user_passwd:
import base64
auth = base64.b64encode(user_passwd).strip()
else:
auth = None
h = httplib.HTTP(host)
if data is not None:
h.putrequest('POST', selector)
h.putheader('Content-Type', 'application/x-www-form-urlencoded')
h.putheader('Content-Length', '%d' % len(data))
else:
h.putrequest('GET', selector)
if proxy_auth: h.putheader('Proxy-Authorization', 'Basic %s' % proxy_auth)
if auth: h.putheader('Authorization', 'Basic %s' % auth)
if realhost: h.putheader('Host', realhost)
for args in self.addheaders: h.putheader(*args)
h.endheaders()
if data is not None:
h.send(data)
errcode, errmsg, headers = h.getreply()
if errcode == -1:
# something went wrong with the HTTP status line
raise IOError, ('http protocol error', 0,
'got a bad status line', None)
fp = h.getfile()
if errcode == 200:
return addinfourl(fp, headers, "http:" + url)
else:
if data is None:
return self.http_error(url, fp, errcode, errmsg, headers)
else:
return self.http_error(url, fp, errcode, errmsg, headers, data)
def http_error(self, url, fp, errcode, errmsg, headers, data=None):
"""Handle http errors.
Derived class can override this, or provide specific handlers
named http_error_DDD where DDD is the 3-digit error code."""
# First check if there's a specific handler for this error
name = 'http_error_%d' % errcode
if hasattr(self, name):
method = getattr(self, name)
if data is None:
result = method(url, fp, errcode, errmsg, headers)
else:
result = method(url, fp, errcode, errmsg, headers, data)
if result: return result
return self.http_error_default(url, fp, errcode, errmsg, headers)
def http_error_default(self, url, fp, errcode, errmsg, headers):
"""Default error handler: close the connection and raise IOError."""
void = fp.read()
fp.close()
raise IOError, ('http error', errcode, errmsg, headers)
if hasattr(socket, "ssl"):
def open_https(self, url, data=None):
"""Use HTTPS protocol."""
import httplib
user_passwd = None
proxy_passwd = None
if isinstance(url, str):
host, selector = splithost(url)
if host:
user_passwd, host = splituser(host)
host = unquote(host)
realhost = host
else:
host, selector = url
# here, we determine, whether the proxy contains authorization information
proxy_passwd, host = splituser(host)
urltype, rest = splittype(selector)
url = rest
user_passwd = None
if urltype.lower() != 'https':
realhost = None
else:
realhost, rest = splithost(rest)
if realhost:
user_passwd, realhost = splituser(realhost)
if user_passwd:
selector = "%s://%s%s" % (urltype, realhost, rest)
#print "proxy via https:", host, selector
if not host: raise IOError, ('https error', 'no host given')
if proxy_passwd:
import base64
proxy_auth = base64.b64encode(proxy_passwd).strip()
else:
proxy_auth = None
if user_passwd:
import base64
auth = base64.b64encode(user_passwd).strip()
else:
auth = None
h = httplib.HTTPS(host, 0,
key_file=self.key_file,
cert_file=self.cert_file)
if data is not None:
h.putrequest('POST', selector)
h.putheader('Content-Type',
'application/x-www-form-urlencoded')
h.putheader('Content-Length', '%d' % len(data))
else:
h.putrequest('GET', selector)
if proxy_auth: h.putheader('Proxy-Authorization', 'Basic %s' % proxy_auth)
if auth: h.putheader('Authorization', 'Basic %s' % auth)
if realhost: h.putheader('Host', realhost)
for args in self.addheaders: h.putheader(*args)
h.endheaders()
if data is not None:
h.send(data)
errcode, errmsg, headers = h.getreply()
if errcode == -1:
# something went wrong with the HTTP status line
raise IOError, ('http protocol error', 0,
'got a bad status line', None)
fp = h.getfile()
if errcode == 200:
return addinfourl(fp, headers, "https:" + url)
else:
if data is None:
return self.http_error(url, fp, errcode, errmsg, headers)
else:
return self.http_error(url, fp, errcode, errmsg, headers,
data)
def open_gopher(self, url):
"""Use Gopher protocol."""
if not isinstance(url, str):
raise IOError, ('gopher error', 'proxy support for gopher protocol currently not implemented')
import gopherlib
host, selector = splithost(url)
if not host: raise IOError, ('gopher error', 'no host given')
host = unquote(host)
type, selector = splitgophertype(selector)
selector, query = splitquery(selector)
selector = unquote(selector)
if query:
query = unquote(query)
fp = gopherlib.send_query(selector, query, host)
else:
fp = gopherlib.send_selector(selector, host)
return addinfourl(fp, noheaders(), "gopher:" + url)
def open_file(self, url):
"""Use local file or FTP depending on form of URL."""
if not isinstance(url, str):
raise IOError, ('file error', 'proxy support for file protocol currently not implemented')
if url[:2] == '//' and url[2:3] != '/' and url[2:12].lower() != 'localhost/':
return self.open_ftp(url)
else:
return self.open_local_file(url)
def open_local_file(self, url):
"""Use local file."""
import mimetypes, mimetools, email.Utils
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
host, file = splithost(url)
localname = url2pathname(file)
try:
stats = os.stat(localname)
except OSError, e:
raise IOError(e.errno, e.strerror, e.filename)
size = stats.st_size
modified = email.Utils.formatdate(stats.st_mtime, usegmt=True)
mtype = mimetypes.guess_type(url)[0]
headers = mimetools.Message(StringIO(
'Content-Type: %s\nContent-Length: %d\nLast-modified: %s\n' %
(mtype or 'text/plain', size, modified)))
if not host:
urlfile = file
if file[:1] == '/':
urlfile = 'file://' + file
return addinfourl(open(localname, 'rb'),
headers, urlfile)
host, port = splitport(host)
if not port \
and socket.gethostbyname(host) in (localhost(), thishost()):
urlfile = file
if file[:1] == '/':
urlfile = 'file://' + file
return addinfourl(open(localname, 'rb'),
headers, urlfile)
raise IOError, ('local file error', 'not on local host')
def open_ftp(self, url):
"""Use FTP protocol."""
if not isinstance(url, str):
raise IOError, ('ftp error', 'proxy support for ftp protocol currently not implemented')
import mimetypes, mimetools
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
host, path = splithost(url)
if not host: raise IOError, ('ftp error', 'no host given')
host, port = splitport(host)
user, host = splituser(host)
if user: user, passwd = splitpasswd(user)
else: passwd = None
host = unquote(host)
user = unquote(user or '')
passwd = unquote(passwd or '')
host = socket.gethostbyname(host)
if not port:
import ftplib
port = ftplib.FTP_PORT
else:
port = int(port)
path, attrs = splitattr(path)
path = unquote(path)
dirs = path.split('/')
dirs, file = dirs[:-1], dirs[-1]
if dirs and not dirs[0]: dirs = dirs[1:]
if dirs and not dirs[0]: dirs[0] = '/'
key = user, host, port, '/'.join(dirs)
# XXX thread unsafe!
if len(self.ftpcache) > MAXFTPCACHE:
# Prune the cache, rather arbitrarily
for k in self.ftpcache.keys():
if k != key:
v = self.ftpcache[k]
del self.ftpcache[k]
v.close()
try:
if not key in self.ftpcache:
self.ftpcache[key] = \
ftpwrapper(user, passwd, host, port, dirs)
if not file: type = 'D'
else: type = 'I'
for attr in attrs:
attr, value = splitvalue(attr)
if attr.lower() == 'type' and \
value in ('a', 'A', 'i', 'I', 'd', 'D'):
type = value.upper()
(fp, retrlen) = self.ftpcache[key].retrfile(file, type)
mtype = mimetypes.guess_type("ftp:" + url)[0]
headers = ""
if mtype:
headers += "Content-Type: %s\n" % mtype
if retrlen is not None and retrlen >= 0:
headers += "Content-Length: %d\n" % retrlen
headers = mimetools.Message(StringIO(headers))
return addinfourl(fp, headers, "ftp:" + url)
except ftperrors(), msg:
raise IOError, ('ftp error', msg), sys.exc_info()[2]
def open_data(self, url, data=None):
"""Use "data" URL."""
if not isinstance(url, str):
raise IOError, ('data error', 'proxy support for data protocol currently not implemented')
# ignore POSTed data
#
# syntax of data URLs:
# dataurl := "data:" [ mediatype ] [ ";base64" ] "," data
# mediatype := [ type "/" subtype ] *( ";" parameter )
# data := *urlchar
# parameter := attribute "=" value
import mimetools
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
try:
[type, data] = url.split(',', 1)
except ValueError:
raise IOError, ('data error', 'bad data URL')
if not type:
type = 'text/plain;charset=US-ASCII'
semi = type.rfind(';')
if semi >= 0 and '=' not in type[semi:]:
encoding = type[semi+1:]
type = type[:semi]
else:
encoding = ''
msg = []
msg.append('Date: %s'%time.strftime('%a, %d %b %Y %T GMT',
time.gmtime(time.time())))
msg.append('Content-type: %s' % type)
if encoding == 'base64':
import base64
data = base64.decodestring(data)
else:
data = unquote(data)
msg.append('Content-Length: %d' % len(data))
msg.append('')
msg.append(data)
msg = '\n'.join(msg)
f = StringIO(msg)
headers = mimetools.Message(f, 0)
#f.fileno = None # needed for addinfourl
return addinfourl(f, headers, url)
class FancyURLopener(URLopener):
"""Derived class with handlers for errors we can handle (perhaps)."""
def __init__(self, *args, **kwargs):
URLopener.__init__(self, *args, **kwargs)
self.auth_cache = {}
self.tries = 0
self.maxtries = 10
def http_error_default(self, url, fp, errcode, errmsg, headers):
"""Default error handling -- don't raise an exception."""
return addinfourl(fp, headers, "http:" + url)
def http_error_302(self, url, fp, errcode, errmsg, headers, data=None):
"""Error 302 -- relocated (temporarily)."""
self.tries += 1
if self.maxtries and self.tries >= self.maxtries:
if hasattr(self, "http_error_500"):
meth = self.http_error_500
else:
meth = self.http_error_default
self.tries = 0
return meth(url, fp, 500,
"Internal Server Error: Redirect Recursion", headers)
result = self.redirect_internal(url, fp, errcode, errmsg, headers,
data)
self.tries = 0
return result
def redirect_internal(self, url, fp, errcode, errmsg, headers, data):
if 'location' in headers:
newurl = headers['location']
elif 'uri' in headers:
newurl = headers['uri']
else:
return
void = fp.read()
fp.close()
# In case the server sent a relative URL, join with original:
newurl = basejoin(self.type + ":" + url, newurl)
return self.open(newurl)
def http_error_301(self, url, fp, errcode, errmsg, headers, data=None):
"""Error 301 -- also relocated (permanently)."""
return self.http_error_302(url, fp, errcode, errmsg, headers, data)
def http_error_303(self, url, fp, errcode, errmsg, headers, data=None):
"""Error 303 -- also relocated (essentially identical to 302)."""
return self.http_error_302(url, fp, errcode, errmsg, headers, data)
def http_error_307(self, url, fp, errcode, errmsg, headers, data=None):
"""Error 307 -- relocated, but turn POST into error."""
if data is None:
return self.http_error_302(url, fp, errcode, errmsg, headers, data)
else:
return self.http_error_default(url, fp, errcode, errmsg, headers)
def http_error_401(self, url, fp, errcode, errmsg, headers, data=None):
"""Error 401 -- authentication required.
This function supports Basic authentication only."""
if not 'www-authenticate' in headers:
URLopener.http_error_default(self, url, fp,
errcode, errmsg, headers)
stuff = headers['www-authenticate']
import re
match = re.match('[ \t]*([^ \t]+)[ \t]+realm="([^"]*)"', stuff)
if not match:
URLopener.http_error_default(self, url, fp,
errcode, errmsg, headers)
scheme, realm = match.groups()
if scheme.lower() != 'basic':
URLopener.http_error_default(self, url, fp,
errcode, errmsg, headers)
name = 'retry_' + self.type + '_basic_auth'
if data is None:
return getattr(self,name)(url, realm)
else:
return getattr(self,name)(url, realm, data)
def http_error_407(self, url, fp, errcode, errmsg, headers, data=None):
"""Error 407 -- proxy authentication required.
This function supports Basic authentication only."""
if not 'proxy-authenticate' in headers:
URLopener.http_error_default(self, url, fp,
errcode, errmsg, headers)
stuff = headers['proxy-authenticate']
import re
match = re.match('[ \t]*([^ \t]+)[ \t]+realm="([^"]*)"', stuff)
if not match:
URLopener.http_error_default(self, url, fp,
errcode, errmsg, headers)
scheme, realm = match.groups()
if scheme.lower() != 'basic':
URLopener.http_error_default(self, url, fp,
errcode, errmsg, headers)
name = 'retry_proxy_' + self.type + '_basic_auth'
if data is None:
return getattr(self,name)(url, realm)
else:
return getattr(self,name)(url, realm, data)
def retry_proxy_http_basic_auth(self, url, realm, data=None):
host, selector = splithost(url)
newurl = 'http://' + host + selector
proxy = self.proxies['http']
urltype, proxyhost = splittype(proxy)
proxyhost, proxyselector = splithost(proxyhost)
i = proxyhost.find('@') + 1
proxyhost = proxyhost[i:]
user, passwd = self.get_user_passwd(proxyhost, realm, i)
if not (user or passwd): return None
proxyhost = quote(user, safe='') + ':' + quote(passwd, safe='') + '@' + proxyhost
self.proxies['http'] = 'http://' + proxyhost + proxyselector
if data is None:
return self.open(newurl)
else:
return self.open(newurl, data)
def retry_proxy_https_basic_auth(self, url, realm, data=None):
host, selector = splithost(url)
newurl = 'https://' + host + selector
proxy = self.proxies['https']
urltype, proxyhost = splittype(proxy)
proxyhost, proxyselector = splithost(proxyhost)
i = proxyhost.find('@') + 1
proxyhost = proxyhost[i:]
user, passwd = self.get_user_passwd(proxyhost, realm, i)
if not (user or passwd): return None
proxyhost = quote(user, safe='') + ':' + quote(passwd, safe='') + '@' + proxyhost
self.proxies['https'] = 'https://' + proxyhost + proxyselector
if data is None:
return self.open(newurl)
else:
return self.open(newurl, data)
def retry_http_basic_auth(self, url, realm, data=None):
host, selector = splithost(url)
i = host.find('@') + 1
host = host[i:]
user, passwd = self.get_user_passwd(host, realm, i)
if not (user or passwd): return None
host = quote(user, safe='') + ':' + quote(passwd, safe='') + '@' + host
newurl = 'http://' + host + selector
if data is None:
return self.open(newurl)
else:
return self.open(newurl, data)
def retry_https_basic_auth(self, url, realm, data=None):
host, selector = splithost(url)
i = host.find('@') + 1
host = host[i:]
user, passwd = self.get_user_passwd(host, realm, i)
if not (user or passwd): return None
host = quote(user, safe='') + ':' + quote(passwd, safe='') + '@' + host
newurl = 'https://' + host + selector
if data is None:
return self.open(newurl)
else:
return self.open(newurl, data)
def get_user_passwd(self, host, realm, clear_cache = 0):
key = realm + '@' + host.lower()
if key in self.auth_cache:
if clear_cache:
del self.auth_cache[key]
else:
return self.auth_cache[key]
user, passwd = self.prompt_user_passwd(host, realm)
if user or passwd: self.auth_cache[key] = (user, passwd)
return user, passwd
def prompt_user_passwd(self, host, realm):
"""Override this in a GUI environment!"""
import getpass
try:
user = raw_input("Enter username for %s at %s: " % (realm,
host))
passwd = getpass.getpass("Enter password for %s in %s at %s: " %
(user, realm, host))
return user, passwd
except KeyboardInterrupt:
print
return None, None
# Utility functions
_localhost = None
def localhost():
"""Return the IP address of the magic hostname 'localhost'."""
global _localhost
if _localhost is None:
_localhost = socket.gethostbyname('localhost')
return _localhost
_thishost = None
def thishost():
"""Return the IP address of the current host."""
global _thishost
if _thishost is None:
_thishost = socket.gethostbyname(socket.gethostname())
return _thishost
_ftperrors = None
def ftperrors():
"""Return the set of errors raised by the FTP class."""
global _ftperrors
if _ftperrors is None:
import ftplib
_ftperrors = ftplib.all_errors
return _ftperrors
_noheaders = None
def noheaders():
"""Return an empty mimetools.Message object."""
global _noheaders
if _noheaders is None:
import mimetools
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
_noheaders = mimetools.Message(StringIO(), 0)
_noheaders.fp.close() # Recycle file descriptor
return _noheaders
# Utility classes
class ftpwrapper:
"""Class used by open_ftp() for cache of open FTP connections."""
def __init__(self, user, passwd, host, port, dirs):
self.user = user
self.passwd = passwd
self.host = host
self.port = port
self.dirs = dirs
self.init()
def init(self):
import ftplib
self.busy = 0
self.ftp = ftplib.FTP()
self.ftp.connect(self.host, self.port)
self.ftp.login(self.user, self.passwd)
for dir in self.dirs:
self.ftp.cwd(dir)
def retrfile(self, file, type):
import ftplib
self.endtransfer()
if type in ('d', 'D'): cmd = 'TYPE A'; isdir = 1
else: cmd = 'TYPE ' + type; isdir = 0
try:
self.ftp.voidcmd(cmd)
except ftplib.all_errors:
self.init()
self.ftp.voidcmd(cmd)
conn = None
if file and not isdir:
# Try to retrieve as a file
try:
cmd = 'RETR ' + file
conn = self.ftp.ntransfercmd(cmd)
except ftplib.error_perm, reason:
if str(reason)[:3] != '550':
raise IOError, ('ftp error', reason), sys.exc_info()[2]
if not conn:
# Set transfer mode to ASCII!
self.ftp.voidcmd('TYPE A')
# Try a directory listing
if file: cmd = 'LIST ' + file
else: cmd = 'LIST'
conn = self.ftp.ntransfercmd(cmd)
self.busy = 1
# Pass back both a suitably decorated object and a retrieval length
return (addclosehook(conn[0].makefile('rb'),
self.endtransfer), conn[1])
def endtransfer(self):
if not self.busy:
return
self.busy = 0
try:
self.ftp.voidresp()
except ftperrors():
pass
def close(self):
self.endtransfer()
try:
self.ftp.close()
except ftperrors():
pass
class addbase:
"""Base class for addinfo and addclosehook."""
def __init__(self, fp):
self.fp = fp
self.read = self.fp.read
self.readline = self.fp.readline
if hasattr(self.fp, "readlines"): self.readlines = self.fp.readlines
if hasattr(self.fp, "fileno"):
self.fileno = self.fp.fileno
else:
self.fileno = lambda: None
if hasattr(self.fp, "__iter__"):
self.__iter__ = self.fp.__iter__
if hasattr(self.fp, "next"):
self.next = self.fp.next
def __repr__(self):
return '<%s at %r whose fp = %r>' % (self.__class__.__name__,
id(self), self.fp)
def close(self):
self.read = None
self.readline = None
self.readlines = None
self.fileno = None
if self.fp: self.fp.close()
self.fp = None
class addclosehook(addbase):
"""Class to add a close hook to an open file."""
def __init__(self, fp, closehook, *hookargs):
addbase.__init__(self, fp)
self.closehook = closehook
self.hookargs = hookargs
def close(self):
addbase.close(self)
if self.closehook:
self.closehook(*self.hookargs)
self.closehook = None
self.hookargs = None
class addinfo(addbase):
"""class to add an info() method to an open file."""
def __init__(self, fp, headers):
addbase.__init__(self, fp)
self.headers = headers
def info(self):
return self.headers
class addinfourl(addbase):
"""class to add info() and geturl() methods to an open file."""
def __init__(self, fp, headers, url):
addbase.__init__(self, fp)
self.headers = headers
self.url = url
def info(self):
return self.headers
def geturl(self):
return self.url
# Utilities to parse URLs (most of these return None for missing parts):
# unwrap('<URL:type://host/path>') --> 'type://host/path'
# splittype('type:opaquestring') --> 'type', 'opaquestring'
# splithost('//host[:port]/path') --> 'host[:port]', '/path'
# splituser('user[:passwd]@host[:port]') --> 'user[:passwd]', 'host[:port]'
# splitpasswd('user:passwd') -> 'user', 'passwd'
# splitport('host:port') --> 'host', 'port'
# splitquery('/path?query') --> '/path', 'query'
# splittag('/path#tag') --> '/path', 'tag'
# splitattr('/path;attr1=value1;attr2=value2;...') ->
# '/path', ['attr1=value1', 'attr2=value2', ...]
# splitvalue('attr=value') --> 'attr', 'value'
# splitgophertype('/Xselector') --> 'X', 'selector'
# unquote('abc%20def') -> 'abc def'
# quote('abc def') -> 'abc%20def')
try:
unicode
except NameError:
def _is_unicode(x):
return 0
else:
def _is_unicode(x):
return isinstance(x, unicode)
def toBytes(url):
"""toBytes(u"URL") --> 'URL'."""
# Most URL schemes require ASCII. If that changes, the conversion
# can be relaxed
if _is_unicode(url):
try:
url = url.encode("ASCII")
except UnicodeError:
raise UnicodeError("URL " + repr(url) +
" contains non-ASCII characters")
return url
def unwrap(url):
"""unwrap('<URL:type://host/path>') --> 'type://host/path'."""
url = url.strip()
if url[:1] == '<' and url[-1:] == '>':
url = url[1:-1].strip()
if url[:4] == 'URL:': url = url[4:].strip()
return url
_typeprog = None
def splittype(url):
"""splittype('type:opaquestring') --> 'type', 'opaquestring'."""
global _typeprog
if _typeprog is None:
import re
_typeprog = re.compile('^([^/:]+):')
match = _typeprog.match(url)
if match:
scheme = match.group(1)
return scheme.lower(), url[len(scheme) + 1:]
return None, url
_hostprog = None
def splithost(url):
"""splithost('//host[:port]/path') --> 'host[:port]', '/path'."""
global _hostprog
if _hostprog is None:
import re
_hostprog = re.compile('^//([^/?]*)(.*)$')
match = _hostprog.match(url)
if match: return match.group(1, 2)
return None, url
_userprog = None
def splituser(host):
"""splituser('user[:passwd]@host[:port]') --> 'user[:passwd]', 'host[:port]'."""
global _userprog
if _userprog is None:
import re
_userprog = re.compile('^(.*)@(.*)$')
match = _userprog.match(host)
if match: return map(unquote, match.group(1, 2))
return None, host
_passwdprog = None
def splitpasswd(user):
"""splitpasswd('user:passwd') -> 'user', 'passwd'."""
global _passwdprog
if _passwdprog is None:
import re
_passwdprog = re.compile('^([^:]*):(.*)$')
match = _passwdprog.match(user)
if match: return match.group(1, 2)
return user, None
# splittag('/path#tag') --> '/path', 'tag'
_portprog = None
def splitport(host):
"""splitport('host:port') --> 'host', 'port'."""
global _portprog
if _portprog is None:
import re
_portprog = re.compile('^(.*):([0-9]+)$')
match = _portprog.match(host)
if match: return match.group(1, 2)
return host, None
_nportprog = None
def splitnport(host, defport=-1):
"""Split host and port, returning numeric port.
Return given default port if no ':' found; defaults to -1.
Return numerical port if a valid number are found after ':'.
Return None if ':' but not a valid number."""
global _nportprog
if _nportprog is None:
import re
_nportprog = re.compile('^(.*):(.*)$')
match = _nportprog.match(host)
if match:
host, port = match.group(1, 2)
try:
if not port: raise ValueError, "no digits"
nport = int(port)
except ValueError:
nport = None
return host, nport
return host, defport
_queryprog = None
def splitquery(url):
"""splitquery('/path?query') --> '/path', 'query'."""
global _queryprog
if _queryprog is None:
import re
_queryprog = re.compile('^(.*)\?([^?]*)$')
match = _queryprog.match(url)
if match: return match.group(1, 2)
return url, None
_tagprog = None
def splittag(url):
"""splittag('/path#tag') --> '/path', 'tag'."""
global _tagprog
if _tagprog is None:
import re
_tagprog = re.compile('^(.*)#([^#]*)$')
match = _tagprog.match(url)
if match: return match.group(1, 2)
return url, None
def splitattr(url):
"""splitattr('/path;attr1=value1;attr2=value2;...') ->
'/path', ['attr1=value1', 'attr2=value2', ...]."""
words = url.split(';')
return words[0], words[1:]
_valueprog = None
def splitvalue(attr):
"""splitvalue('attr=value') --> 'attr', 'value'."""
global _valueprog
if _valueprog is None:
import re
_valueprog = re.compile('^([^=]*)=(.*)$')
match = _valueprog.match(attr)
if match: return match.group(1, 2)
return attr, None
def splitgophertype(selector):
"""splitgophertype('/Xselector') --> 'X', 'selector'."""
if selector[:1] == '/' and selector[1:2]:
return selector[1], selector[2:]
return None, selector
_hextochr = dict(('%02x' % i, chr(i)) for i in range(256))
_hextochr.update(('%02X' % i, chr(i)) for i in range(256))
def unquote(s):
"""unquote('abc%20def') -> 'abc def'."""
res = s.split('%')
for i in xrange(1, len(res)):
item = res[i]
try:
res[i] = _hextochr[item[:2]] + item[2:]
except KeyError:
res[i] = '%' + item
except UnicodeDecodeError:
res[i] = unichr(int(item[:2], 16)) + item[2:]
return "".join(res)
def unquote_plus(s):
"""unquote('%7e/abc+def') -> '~/abc def'"""
s = s.replace('+', ' ')
return unquote(s)
always_safe = ('ABCDEFGHIJKLMNOPQRSTUVWXYZ'
'abcdefghijklmnopqrstuvwxyz'
'0123456789' '_.-')
_safemaps = {}
def quote(s, safe = '/'):
"""quote('abc def') -> 'abc%20def'
Each part of a URL, e.g. the path info, the query, etc., has a
different set of reserved characters that must be quoted.
RFC 2396 Uniform Resource Identifiers (URI): Generic Syntax lists
the following reserved characters.
reserved = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
"$" | ","
Each of these characters is reserved in some component of a URL,
but not necessarily in all of them.
By default, the quote function is intended for quoting the path
section of a URL. Thus, it will not encode '/'. This character
is reserved, but in typical usage the quote function is being
called on a path where the existing slash characters are used as
reserved characters.
"""
cachekey = (safe, always_safe)
try:
safe_map = _safemaps[cachekey]
except KeyError:
safe += always_safe
safe_map = {}
for i in range(256):
c = chr(i)
safe_map[c] = (c in safe) and c or ('%%%02X' % i)
_safemaps[cachekey] = safe_map
res = map(safe_map.__getitem__, s)
return ''.join(res)
def quote_plus(s, safe = ''):
"""Quote the query fragment of a URL; replacing ' ' with '+'"""
if ' ' in s:
s = quote(s, safe + ' ')
return s.replace(' ', '+')
return quote(s, safe)
def urlencode(query,doseq=0):
"""Encode a sequence of two-element tuples or dictionary into a URL query string.
If any values in the query arg are sequences and doseq is true, each
sequence element is converted to a separate parameter.
If the query arg is a sequence of two-element tuples, the order of the
parameters in the output will match the order of parameters in the
input.
"""
if hasattr(query,"items"):
# mapping objects
query = query.items()
else:
# it's a bother at times that strings and string-like objects are
# sequences...
try:
# non-sequence items should not work with len()
# non-empty strings will fail this
if len(query) and not isinstance(query[0], tuple):
raise TypeError
# zero-length sequences of all types will get here and succeed,
# but that's a minor nit - since the original implementation
# allowed empty dicts that type of behavior probably should be
# preserved for consistency
except TypeError:
ty,va,tb = sys.exc_info()
raise TypeError, "not a valid non-string sequence or mapping object", tb
l = []
if not doseq:
# preserve old behavior
for k, v in query:
k = quote_plus(str(k))
v = quote_plus(str(v))
l.append(k + '=' + v)
else:
for k, v in query:
k = quote_plus(str(k))
if isinstance(v, str):
v = quote_plus(v)
l.append(k + '=' + v)
elif _is_unicode(v):
# is there a reasonable way to convert to ASCII?
# encode generates a string, but "replace" or "ignore"
# lose information and "strict" can raise UnicodeError
v = quote_plus(v.encode("ASCII","replace"))
l.append(k + '=' + v)
else:
try:
# is this a sufficient test for sequence-ness?
x = len(v)
except TypeError:
# not a sequence
v = quote_plus(str(v))
l.append(k + '=' + v)
else:
# loop over the sequence
for elt in v:
l.append(k + '=' + quote_plus(str(elt)))
return '&'.join(l)
# Proxy handling
def getproxies_environment():
"""Return a dictionary of scheme -> proxy server URL mappings.
Scan the environment for variables named <scheme>_proxy;
this seems to be the standard convention. If you need a
different way, you can pass a proxies dictionary to the
[Fancy]URLopener constructor.
"""
proxies = {}
for name, value in os.environ.items():
name = name.lower()
if value and name[-6:] == '_proxy':
proxies[name[:-6]] = value
return proxies
if sys.platform == 'darwin':
def getproxies_internetconfig():
"""Return a dictionary of scheme -> proxy server URL mappings.
By convention the mac uses Internet Config to store
proxies. An HTTP proxy, for instance, is stored under
the HttpProxy key.
"""
try:
import ic
except ImportError:
return {}
try:
config = ic.IC()
except ic.error:
return {}
proxies = {}
# HTTP:
if 'UseHTTPProxy' in config and config['UseHTTPProxy']:
try:
value = config['HTTPProxyHost']
except ic.error:
pass
else:
proxies['http'] = 'http://%s' % value
# FTP: XXXX To be done.
# Gopher: XXXX To be done.
return proxies
def proxy_bypass(x):
return 0
def getproxies():
return getproxies_environment() or getproxies_internetconfig()
elif os.name == 'nt':
def getproxies_registry():
"""Return a dictionary of scheme -> proxy server URL mappings.
Win32 uses the registry to store proxies.
"""
proxies = {}
try:
import _winreg
except ImportError:
# Std module, so should be around - but you never know!
return proxies
try:
internetSettings = _winreg.OpenKey(_winreg.HKEY_CURRENT_USER,
r'Software\Microsoft\Windows\CurrentVersion\Internet Settings')
proxyEnable = _winreg.QueryValueEx(internetSettings,
'ProxyEnable')[0]
if proxyEnable:
# Returned as Unicode but problems if not converted to ASCII
proxyServer = str(_winreg.QueryValueEx(internetSettings,
'ProxyServer')[0])
if '=' in proxyServer:
# Per-protocol settings
for p in proxyServer.split(';'):
protocol, address = p.split('=', 1)
# See if address has a type:// prefix
import re
if not re.match('^([^/:]+)://', address):
address = '%s://%s' % (protocol, address)
proxies[protocol] = address
else:
# Use one setting for all protocols
if proxyServer[:5] == 'http:':
proxies['http'] = proxyServer
else:
proxies['http'] = 'http://%s' % proxyServer
proxies['ftp'] = 'ftp://%s' % proxyServer
internetSettings.Close()
except (WindowsError, ValueError, TypeError):
# Either registry key not found etc, or the value in an
# unexpected format.
# proxies already set up to be empty so nothing to do
pass
return proxies
def getproxies():
"""Return a dictionary of scheme -> proxy server URL mappings.
Returns settings gathered from the environment, if specified,
or the registry.
"""
return getproxies_environment() or getproxies_registry()
def proxy_bypass(host):
try:
import _winreg
import re
except ImportError:
# Std modules, so should be around - but you never know!
return 0
try:
internetSettings = _winreg.OpenKey(_winreg.HKEY_CURRENT_USER,
r'Software\Microsoft\Windows\CurrentVersion\Internet Settings')
proxyEnable = _winreg.QueryValueEx(internetSettings,
'ProxyEnable')[0]
proxyOverride = str(_winreg.QueryValueEx(internetSettings,
'ProxyOverride')[0])
# ^^^^ Returned as Unicode but problems if not converted to ASCII
except WindowsError:
return 0
if not proxyEnable or not proxyOverride:
return 0
# try to make a host list from name and IP address.
rawHost, port = splitport(host)
host = [rawHost]
try:
addr = socket.gethostbyname(rawHost)
if addr != rawHost:
host.append(addr)
except socket.error:
pass
try:
fqdn = socket.getfqdn(rawHost)
if fqdn != rawHost:
host.append(fqdn)
except socket.error:
pass
# make a check value list from the registry entry: replace the
# '<local>' string by the localhost entry and the corresponding
# canonical entry.
proxyOverride = proxyOverride.split(';')
i = 0
while i < len(proxyOverride):
if proxyOverride[i] == '<local>':
proxyOverride[i:i+1] = ['localhost',
'127.0.0.1',
socket.gethostname(),
socket.gethostbyname(
socket.gethostname())]
i += 1
# print proxyOverride
# now check if we match one of the registry values.
for test in proxyOverride:
test = test.replace(".", r"\.") # mask dots
test = test.replace("*", r".*") # change glob sequence
test = test.replace("?", r".") # change glob char
for val in host:
# print "%s <--> %s" %( test, val )
if re.match(test, val, re.I):
return 1
return 0
else:
# By default use environment variables
getproxies = getproxies_environment
def proxy_bypass(host):
return 0
# Test and time quote() and unquote()
def test1():
s = ''
for i in range(256): s = s + chr(i)
s = s*4
t0 = time.time()
qs = quote(s)
uqs = unquote(qs)
t1 = time.time()
if uqs != s:
print 'Wrong!'
print repr(s)
print repr(qs)
print repr(uqs)
print round(t1 - t0, 3), 'sec'
def reporthook(blocknum, blocksize, totalsize):
# Report during remote transfers
print "Block number: %d, Block size: %d, Total size: %d" % (
blocknum, blocksize, totalsize)
# Test program
def test(args=[]):
if not args:
args = [
'/etc/passwd',
'file:/etc/passwd',
'file://localhost/etc/passwd',
'ftp://ftp.gnu.org/pub/README',
## 'gopher://gopher.micro.umn.edu/1/',
'http://www.python.org/index.html',
]
if hasattr(URLopener, "open_https"):
args.append('https://synergy.as.cmu.edu/~geek/')
try:
for url in args:
print '-'*10, url, '-'*10
fn, h = urlretrieve(url, None, reporthook)
print fn
if h:
print '======'
for k in h.keys(): print k + ':', h[k]
print '======'
fp = open(fn, 'rb')
data = fp.read()
del fp
if '\r' in data:
table = string.maketrans("", "")
data = data.translate(table, "\r")
print data
fn, h = None, None
print '-'*40
finally:
urlcleanup()
def main():
import getopt, sys
try:
opts, args = getopt.getopt(sys.argv[1:], "th")
except getopt.error, msg:
print msg
print "Use -h for help"
return
t = 0
for o, a in opts:
if o == '-t':
t = t + 1
if o == '-h':
print "Usage: python urllib.py [-t] [url ...]"
print "-t runs self-test;",
print "otherwise, contents of urls are printed"
return
if t:
if t > 1:
test1()
test(args)
else:
if not args:
print "Use -h for help"
for url in args:
print urlopen(url).read(),
# Run test program when run as a script
if __name__ == '__main__':
main()