cpython/Lib/httplib.py
Jeremy Hylton d4c472c3e2 Move code for reading chunked responses in helper function,
along with some small changes (e.g. use of +=).
2002-09-03 20:49:06 +00:00

1268 lines
42 KiB
Python

"""HTTP/1.1 client library
<intro stuff goes here>
<other stuff, too>
HTTPConnection go through a number of "states", which defines when a client
may legally make another request or fetch the response for a particular
request. This diagram details these state transitions:
(null)
|
| HTTPConnection()
v
Idle
|
| putrequest()
v
Request-started
|
| ( putheader() )* endheaders()
v
Request-sent
|
| response = getresponse()
v
Unread-response [Response-headers-read]
|\____________________
| |
| response.read() | putrequest()
v v
Idle Req-started-unread-response
______/|
/ |
response.read() | | ( putheader() )* endheaders()
v v
Request-started Req-sent-unread-response
|
| response.read()
v
Request-sent
This diagram presents the following rules:
-- a second request may not be started until {response-headers-read}
-- a response [object] cannot be retrieved until {request-sent}
-- there is no differentiation between an unread response body and a
partially read response body
Note: this enforcement is applied by the HTTPConnection class. The
HTTPResponse class does not enforce this state machine, which
implies sophisticated clients may accelerate the request/response
pipeline. Caution should be taken, though: accelerating the states
beyond the above pattern may imply knowledge of the server's
connection-close behavior for certain requests. For example, it
is impossible to tell whether the server will close the connection
UNTIL the response headers have been read; this means that further
requests cannot be placed into the pipeline until it is known that
the server will NOT be closing the connection.
Logical State __state __response
------------- ------- ----------
Idle _CS_IDLE None
Request-started _CS_REQ_STARTED None
Request-sent _CS_REQ_SENT None
Unread-response _CS_IDLE <response_class>
Req-started-unread-response _CS_REQ_STARTED <response_class>
Req-sent-unread-response _CS_REQ_SENT <response_class>
"""
import errno
import mimetools
import socket
from urlparse import urlsplit
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
__all__ = ["HTTP", "HTTPResponse", "HTTPConnection", "HTTPSConnection",
"HTTPException", "NotConnected", "UnknownProtocol",
"UnknownTransferEncoding", "UnimplementedFileMode",
"IncompleteRead", "InvalidURL", "ImproperConnectionState",
"CannotSendRequest", "CannotSendHeader", "ResponseNotReady",
"BadStatusLine", "error"]
HTTP_PORT = 80
HTTPS_PORT = 443
_UNKNOWN = 'UNKNOWN'
# connection states
_CS_IDLE = 'Idle'
_CS_REQ_STARTED = 'Request-started'
_CS_REQ_SENT = 'Request-sent'
class HTTPMessage(mimetools.Message):
def addheader(self, key, value):
"""Add header for field key handling repeats."""
prev = self.dict.get(key)
if prev is None:
self.dict[key] = value
else:
combined = ", ".join((prev, value))
self.dict[key] = combined
def addcontinue(self, key, more):
"""Add more field data from a continuation line."""
prev = self.dict[key]
self.dict[key] = prev + "\n " + more
def readheaders(self):
"""Read header lines.
Read header lines up to the entirely blank line that terminates them.
The (normally blank) line that ends the headers is skipped, but not
included in the returned list. If a non-header line ends the headers,
(which is an error), an attempt is made to backspace over it; it is
never included in the returned list.
The variable self.status is set to the empty string if all went well,
otherwise it is an error message. The variable self.headers is a
completely uninterpreted list of lines contained in the header (so
printing them will reproduce the header exactly as it appears in the
file).
If multiple header fields with the same name occur, they are combined
according to the rules in RFC 2616 sec 4.2:
Appending each subsequent field-value to the first, each separated
by a comma. The order in which header fields with the same field-name
are received is significant to the interpretation of the combined
field value.
"""
# XXX The implementation overrides the readheaders() method of
# rfc822.Message. The base class design isn't amenable to
# customized behavior here so the method here is a copy of the
# base class code with a few small changes.
self.dict = {}
self.unixfrom = ''
self.headers = list = []
self.status = ''
headerseen = ""
firstline = 1
startofline = unread = tell = None
if hasattr(self.fp, 'unread'):
unread = self.fp.unread
elif self.seekable:
tell = self.fp.tell
while 1:
if tell:
try:
startofline = tell()
except IOError:
startofline = tell = None
self.seekable = 0
line = self.fp.readline()
if not line:
self.status = 'EOF in headers'
break
# Skip unix From name time lines
if firstline and line.startswith('From '):
self.unixfrom = self.unixfrom + line
continue
firstline = 0
if headerseen and line[0] in ' \t':
# XXX Not sure if continuation lines are handled properly
# for http and/or for repeating headers
# It's a continuation line.
list.append(line)
x = self.dict[headerseen] + "\n " + line.strip()
self.addcontinue(headerseen, line.strip())
continue
elif self.iscomment(line):
# It's a comment. Ignore it.
continue
elif self.islast(line):
# Note! No pushback here! The delimiter line gets eaten.
break
headerseen = self.isheader(line)
if headerseen:
# It's a legal header line, save it.
list.append(line)
self.addheader(headerseen, line[len(headerseen)+1:].strip())
continue
else:
# It's not a header line; throw it back and stop here.
if not self.dict:
self.status = 'No headers'
else:
self.status = 'Non-header line where header expected'
# Try to undo the read.
if unread:
unread(line)
elif tell:
self.fp.seek(startofline)
else:
self.status = self.status + '; bad seek'
break
class HTTPResponse:
# strict: If true, raise BadStatusLine if the status line can't be
# parsed as a valid HTTP/1.0 or 1.1 status line. By default it is
# false because it prevents clients from talking to HTTP/0.9
# servers. Note that a response with a sufficiently corrupted
# status line will look like an HTTP/0.9 response.
# See RFC 2616 sec 19.6 and RFC 1945 sec 6 for details.
def __init__(self, sock, debuglevel=0, strict=0):
self.fp = sock.makefile('rb', 0)
self.debuglevel = debuglevel
self.strict = strict
self.msg = None
# from the Status-Line of the response
self.version = _UNKNOWN # HTTP-Version
self.status = _UNKNOWN # Status-Code
self.reason = _UNKNOWN # Reason-Phrase
self.chunked = _UNKNOWN # is "chunked" being used?
self.chunk_left = _UNKNOWN # bytes left to read in current chunk
self.length = _UNKNOWN # number of bytes left in response
self.will_close = _UNKNOWN # conn will close at end of response
def _read_status(self):
# Initialize with Simple-Response defaults
line = self.fp.readline()
if self.debuglevel > 0:
print "reply:", repr(line)
try:
[version, status, reason] = line.split(None, 2)
except ValueError:
try:
[version, status] = line.split(None, 1)
reason = ""
except ValueError:
# empty version will cause next test to fail and status
# will be treated as 0.9 response.
version = ""
if not version.startswith('HTTP/'):
if self.strict:
self.close()
raise BadStatusLine(line)
else:
# assume it's a Simple-Response from an 0.9 server
self.fp = LineAndFileWrapper(line, self.fp)
return "HTTP/0.9", 200, ""
# The status code is a three-digit number
try:
status = int(status)
if status < 100 or status > 999:
raise BadStatusLine(line)
except ValueError:
raise BadStatusLine(line)
return version, status, reason
def begin(self):
if self.msg is not None:
# we've already started reading the response
return
# read until we get a non-100 response
while 1:
version, status, reason = self._read_status()
if status != 100:
break
# skip the header from the 100 response
while 1:
skip = self.fp.readline().strip()
if not skip:
break
if self.debuglevel > 0:
print "header:", skip
self.status = status
self.reason = reason.strip()
if version == 'HTTP/1.0':
self.version = 10
elif version.startswith('HTTP/1.'):
self.version = 11 # use HTTP/1.1 code for HTTP/1.x where x>=1
elif version == 'HTTP/0.9':
self.version = 9
else:
raise UnknownProtocol(version)
if self.version == 9:
self.chunked = 0
self.will_close = 1
self.msg = HTTPMessage(StringIO())
return
self.msg = HTTPMessage(self.fp, 0)
if self.debuglevel > 0:
for hdr in self.msg.headers:
print "header:", hdr,
# don't let the msg keep an fp
self.msg.fp = None
# are we using the chunked-style of transfer encoding?
tr_enc = self.msg.getheader('transfer-encoding')
if tr_enc and tr_enc.lower() == "chunked":
self.chunked = 1
self.chunk_left = None
else:
self.chunked = 0
# will the connection close at the end of the response?
conn = self.msg.getheader('connection')
if conn:
conn = conn.lower()
# a "Connection: close" will always close the connection. if we
# don't see that and this is not HTTP/1.1, then the connection will
# close unless we see a Keep-Alive header.
self.will_close = conn.find('close') != -1 or \
( self.version != 11 and \
not self.msg.getheader('keep-alive') )
else:
# for HTTP/1.1, the connection will always remain open
# otherwise, it will remain open IFF we see a Keep-Alive header
self.will_close = self.version != 11 and \
not self.msg.getheader('keep-alive')
# do we have a Content-Length?
# NOTE: RFC 2616, S4.4, #3 says we ignore this if tr_enc is "chunked"
length = self.msg.getheader('content-length')
if length and not self.chunked:
try:
self.length = int(length)
except ValueError:
self.length = None
else:
self.length = None
# does the body have a fixed length? (of zero)
if (status == 204 or # No Content
status == 304 or # Not Modified
100 <= status < 200): # 1xx codes
self.length = 0
# if the connection remains open, and we aren't using chunked, and
# a content-length was not provided, then assume that the connection
# WILL close.
if not self.will_close and \
not self.chunked and \
self.length is None:
self.will_close = 1
def close(self):
if self.fp:
self.fp.close()
self.fp = None
def isclosed(self):
# NOTE: it is possible that we will not ever call self.close(). This
# case occurs when will_close is TRUE, length is None, and we
# read up to the last byte, but NOT past it.
#
# IMPLIES: if will_close is FALSE, then self.close() will ALWAYS be
# called, meaning self.isclosed() is meaningful.
return self.fp is None
def read(self, amt=None):
if self.fp is None:
return ''
if self.chunked:
return self._read_chunked(amt)
if amt is None:
# unbounded read
if self.will_close:
s = self.fp.read()
else:
s = self._safe_read(self.length)
self.close() # we read everything
return s
if self.length is not None:
if amt > self.length:
# clip the read to the "end of response"
amt = self.length
self.length -= amt
# we do not use _safe_read() here because this may be a .will_close
# connection, and the user is reading more bytes than will be provided
# (for example, reading in 1k chunks)
s = self.fp.read(amt)
return s
def _read_chunked(self, amt):
assert self.chunked != _UNKNOWN
chunk_left = self.chunk_left
value = ''
# XXX This accumulates chunks by repeated string concatenation,
# which is not efficient as the number or size of chunks gets big.
while 1:
if chunk_left is None:
line = self.fp.readline()
i = line.find(';')
if i >= 0:
line = line[:i] # strip chunk-extensions
chunk_left = int(line, 16)
if chunk_left == 0:
break
if amt is None:
value += self._safe_read(chunk_left)
elif amt < chunk_left:
value += self._safe_read(amt)
self.chunk_left = chunk_left - amt
return value
elif amt == chunk_left:
value += self._safe_read(amt)
self._safe_read(2) # toss the CRLF at the end of the chunk
self.chunk_left = None
return value
else:
value += self._safe_read(chunk_left)
amt -= chunk_left
# we read the whole chunk, get another
self._safe_read(2) # toss the CRLF at the end of the chunk
chunk_left = None
# read and discard trailer up to the CRLF terminator
### note: we shouldn't have any trailers!
while 1:
line = self.fp.readline()
if line == '\r\n':
break
# we read everything; close the "file"
# XXX Shouldn't the client close the file?
self.close()
return value
def _safe_read(self, amt):
"""Read the number of bytes requested, compensating for partial reads.
Normally, we have a blocking socket, but a read() can be interrupted
by a signal (resulting in a partial read).
Note that we cannot distinguish between EOF and an interrupt when zero
bytes have been read. IncompleteRead() will be raised in this
situation.
This function should be used when <amt> bytes "should" be present for
reading. If the bytes are truly not available (due to EOF), then the
IncompleteRead exception can be used to detect the problem.
"""
s = ''
while amt > 0:
chunk = self.fp.read(amt)
if not chunk:
raise IncompleteRead(s)
s = s + chunk
amt = amt - len(chunk)
return s
def getheader(self, name, default=None):
if self.msg is None:
raise ResponseNotReady()
return self.msg.getheader(name, default)
class HTTPConnection:
_http_vsn = 11
_http_vsn_str = 'HTTP/1.1'
response_class = HTTPResponse
default_port = HTTP_PORT
auto_open = 1
debuglevel = 0
strict = 0
def __init__(self, host, port=None, strict=None):
self.sock = None
self._buffer = []
self.__response = None
self.__state = _CS_IDLE
self._set_hostport(host, port)
if strict is not None:
self.strict = strict
def _set_hostport(self, host, port):
if port is None:
i = host.find(':')
if i >= 0:
try:
port = int(host[i+1:])
except ValueError:
raise InvalidURL("nonnumeric port: '%s'" % host[i+1:])
host = host[:i]
else:
port = self.default_port
self.host = host
self.port = port
def set_debuglevel(self, level):
self.debuglevel = level
def connect(self):
"""Connect to the host and port specified in __init__."""
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:
self.sock = socket.socket(af, socktype, proto)
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
def close(self):
"""Close the connection to the HTTP server."""
if self.sock:
self.sock.close() # close it manually... there may be other refs
self.sock = None
if self.__response:
self.__response.close()
self.__response = None
self.__state = _CS_IDLE
def send(self, str):
"""Send `str' to the server."""
if self.sock is None:
if self.auto_open:
self.connect()
else:
raise NotConnected()
# send the data to the server. if we get a broken pipe, then close
# the socket. we want to reconnect when somebody tries to send again.
#
# NOTE: we DO propagate the error, though, because we cannot simply
# ignore the error... the caller will know if they can retry.
if self.debuglevel > 0:
print "send:", repr(str)
try:
self.sock.sendall(str)
except socket.error, v:
if v[0] == 32: # Broken pipe
self.close()
raise
def _output(self, s):
"""Add a line of output to the current request buffer.
Assumes that the line does *not* end with \\r\\n.
"""
self._buffer.append(s)
def _send_output(self):
"""Send the currently buffered request and clear the buffer.
Appends an extra \\r\\n to the buffer.
"""
self._buffer.extend(("", ""))
msg = "\r\n".join(self._buffer)
del self._buffer[:]
self.send(msg)
def putrequest(self, method, url, skip_host=0):
"""Send a request to the server.
`method' specifies an HTTP request method, e.g. 'GET'.
`url' specifies the object being requested, e.g. '/index.html'.
"""
# check if a prior response has been completed
# XXX What if it hasn't?
if self.__response and self.__response.isclosed():
self.__response = None
#
# in certain cases, we cannot issue another request on this connection.
# this occurs when:
# 1) we are in the process of sending a request. (_CS_REQ_STARTED)
# 2) a response to a previous request has signalled that it is going
# to close the connection upon completion.
# 3) the headers for the previous response have not been read, thus
# we cannot determine whether point (2) is true. (_CS_REQ_SENT)
#
# if there is no prior response, then we can request at will.
#
# if point (2) is true, then we will have passed the socket to the
# response (effectively meaning, "there is no prior response"), and
# will open a new one when a new request is made.
#
# Note: if a prior response exists, then we *can* start a new request.
# We are not allowed to begin fetching the response to this new
# request, however, until that prior response is complete.
#
if self.__state == _CS_IDLE:
self.__state = _CS_REQ_STARTED
else:
raise CannotSendRequest()
if not url:
url = '/'
str = '%s %s %s' % (method, url, self._http_vsn_str)
self._output(str)
if self._http_vsn == 11:
# Issue some standard headers for better HTTP/1.1 compliance
if not skip_host:
# this header is issued *only* for HTTP/1.1
# connections. more specifically, this means it is
# only issued when the client uses the new
# HTTPConnection() class. backwards-compat clients
# will be using HTTP/1.0 and those clients may be
# issuing this header themselves. we should NOT issue
# it twice; some web servers (such as Apache) barf
# when they see two Host: headers
# If we need a non-standard port,include it in the
# header. If the request is going through a proxy,
# but the host of the actual URL, not the host of the
# proxy.
netloc = ''
if url.startswith('http'):
nil, netloc, nil, nil, nil = urlsplit(url)
if netloc:
self.putheader('Host', netloc)
elif self.port == HTTP_PORT:
self.putheader('Host', self.host)
else:
self.putheader('Host', "%s:%s" % (self.host, self.port))
# note: we are assuming that clients will not attempt to set these
# headers since *this* library must deal with the
# consequences. this also means that when the supporting
# libraries are updated to recognize other forms, then this
# code should be changed (removed or updated).
# we only want a Content-Encoding of "identity" since we don't
# support encodings such as x-gzip or x-deflate.
self.putheader('Accept-Encoding', 'identity')
# we can accept "chunked" Transfer-Encodings, but no others
# NOTE: no TE header implies *only* "chunked"
#self.putheader('TE', 'chunked')
# if TE is supplied in the header, then it must appear in a
# Connection header.
#self.putheader('Connection', 'TE')
else:
# For HTTP/1.0, the server will assume "not chunked"
pass
def putheader(self, header, value):
"""Send a request header line to the server.
For example: h.putheader('Accept', 'text/html')
"""
if self.__state != _CS_REQ_STARTED:
raise CannotSendHeader()
str = '%s: %s' % (header, value)
self._output(str)
def endheaders(self):
"""Indicate that the last header line has been sent to the server."""
if self.__state == _CS_REQ_STARTED:
self.__state = _CS_REQ_SENT
else:
raise CannotSendHeader()
self._send_output()
def request(self, method, url, body=None, headers={}):
"""Send a complete request to the server."""
try:
self._send_request(method, url, body, headers)
except socket.error, v:
# trap 'Broken pipe' if we're allowed to automatically reconnect
if v[0] != 32 or not self.auto_open:
raise
# try one more time
self._send_request(method, url, body, headers)
def _send_request(self, method, url, body, headers):
# If headers already contains a host header, then define the
# optional skip_host argument to putrequest(). The check is
# harder because field names are case insensitive.
if 'Host' in (headers
or [k for k in headers.iterkeys() if k.lower() == "host"]):
self.putrequest(method, url, skip_host=1)
else:
self.putrequest(method, url)
if body:
self.putheader('Content-Length', str(len(body)))
for hdr, value in headers.items():
self.putheader(hdr, value)
self.endheaders()
if body:
self.send(body)
def getresponse(self):
"Get the response from the server."
# check if a prior response has been completed
if self.__response and self.__response.isclosed():
self.__response = None
#
# if a prior response exists, then it must be completed (otherwise, we
# cannot read this response's header to determine the connection-close
# behavior)
#
# note: if a prior response existed, but was connection-close, then the
# socket and response were made independent of this HTTPConnection
# object since a new request requires that we open a whole new
# connection
#
# this means the prior response had one of two states:
# 1) will_close: this connection was reset and the prior socket and
# response operate independently
# 2) persistent: the response was retained and we await its
# isclosed() status to become true.
#
if self.__state != _CS_REQ_SENT or self.__response:
raise ResponseNotReady()
if self.debuglevel > 0:
response = self.response_class(self.sock, self.debuglevel,
strict=self.strict)
else:
response = self.response_class(self.sock, strict=self.strict)
response.begin()
assert response.will_close != _UNKNOWN
self.__state = _CS_IDLE
if response.will_close:
# this effectively passes the connection to the response
self.close()
else:
# remember this, so we can tell when it is complete
self.__response = response
return response
# The next several classes are used to define FakeSocket,a socket-like
# interface to an SSL connection.
# The primary complexity comes from faking a makefile() method. The
# standard socket makefile() implementation calls dup() on the socket
# file descriptor. As a consequence, clients can call close() on the
# parent socket and its makefile children in any order. The underlying
# socket isn't closed until they are all closed.
# The implementation uses reference counting to keep the socket open
# until the last client calls close(). SharedSocket keeps track of
# the reference counting and SharedSocketClient provides an constructor
# and close() method that call incref() and decref() correctly.
class SharedSocket:
def __init__(self, sock):
self.sock = sock
self._refcnt = 0
def incref(self):
self._refcnt += 1
def decref(self):
self._refcnt -= 1
assert self._refcnt >= 0
if self._refcnt == 0:
self.sock.close()
def __del__(self):
self.sock.close()
class SharedSocketClient:
def __init__(self, shared):
self._closed = 0
self._shared = shared
self._shared.incref()
self._sock = shared.sock
def close(self):
if not self._closed:
self._shared.decref()
self._closed = 1
self._shared = None
class SSLFile(SharedSocketClient):
"""File-like object wrapping an SSL socket."""
BUFSIZE = 8192
def __init__(self, sock, ssl, bufsize=None):
SharedSocketClient.__init__(self, sock)
self._ssl = ssl
self._buf = ''
self._bufsize = bufsize or self.__class__.BUFSIZE
def _read(self):
buf = ''
# put in a loop so that we retry on transient errors
while 1:
try:
buf = self._ssl.read(self._bufsize)
except socket.sslerror, err:
if (err[0] == socket.SSL_ERROR_WANT_READ
or err[0] == socket.SSL_ERROR_WANT_WRITE):
continue
if (err[0] == socket.SSL_ERROR_ZERO_RETURN
or err[0] == socket.SSL_ERROR_EOF):
break
raise
except socket.error, err:
if err[0] == errno.EINTR:
continue
if err[0] == errno.EBADF:
# XXX socket was closed?
break
raise
else:
break
return buf
def read(self, size=None):
L = [self._buf]
avail = len(self._buf)
while size is None or avail < size:
s = self._read()
if s == '':
break
L.append(s)
avail += len(s)
all = "".join(L)
if size is None:
self._buf = ''
return all
else:
self._buf = all[size:]
return all[:size]
def readline(self):
L = [self._buf]
self._buf = ''
while 1:
i = L[-1].find("\n")
if i >= 0:
break
s = self._read()
if s == '':
break
L.append(s)
if i == -1:
# loop exited because there is no more data
return "".join(L)
else:
all = "".join(L)
# XXX could do enough bookkeeping not to do a 2nd search
i = all.find("\n") + 1
line = all[:i]
self._buf = all[i:]
return line
class FakeSocket(SharedSocketClient):
class _closedsocket:
def __getattr__(self, name):
raise error(9, 'Bad file descriptor')
def __init__(self, sock, ssl):
sock = SharedSocket(sock)
SharedSocketClient.__init__(self, sock)
self._ssl = ssl
def close(self):
SharedSocketClient.close(self)
self._sock = self.__class__._closedsocket()
def makefile(self, mode, bufsize=None):
if mode != 'r' and mode != 'rb':
raise UnimplementedFileMode()
return SSLFile(self._shared, self._ssl, bufsize)
def send(self, stuff, flags = 0):
return self._ssl.write(stuff)
sendall = send
def recv(self, len = 1024, flags = 0):
return self._ssl.read(len)
def __getattr__(self, attr):
return getattr(self._sock, attr)
class HTTPSConnection(HTTPConnection):
"This class allows communication via SSL."
default_port = HTTPS_PORT
def __init__(self, host, port=None, key_file=None, cert_file=None,
strict=None):
HTTPConnection.__init__(self, host, port, strict)
self.key_file = key_file
self.cert_file = cert_file
def connect(self):
"Connect to a host on a given (SSL) port."
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect((self.host, self.port))
realsock = sock
if hasattr(sock, "_sock"):
realsock = sock._sock
ssl = socket.ssl(realsock, self.key_file, self.cert_file)
self.sock = FakeSocket(sock, ssl)
class HTTP:
"Compatibility class with httplib.py from 1.5."
_http_vsn = 10
_http_vsn_str = 'HTTP/1.0'
debuglevel = 0
_connection_class = HTTPConnection
def __init__(self, host='', port=None, strict=None):
"Provide a default host, since the superclass requires one."
# some joker passed 0 explicitly, meaning default port
if port == 0:
port = None
# Note that we may pass an empty string as the host; this will throw
# an error when we attempt to connect. Presumably, the client code
# will call connect before then, with a proper host.
self._setup(self._connection_class(host, port, strict))
def _setup(self, conn):
self._conn = conn
# set up delegation to flesh out interface
self.send = conn.send
self.putrequest = conn.putrequest
self.endheaders = conn.endheaders
self.set_debuglevel = conn.set_debuglevel
conn._http_vsn = self._http_vsn
conn._http_vsn_str = self._http_vsn_str
self.file = None
def connect(self, host=None, port=None):
"Accept arguments to set the host/port, since the superclass doesn't."
if host is not None:
self._conn._set_hostport(host, port)
self._conn.connect()
def getfile(self):
"Provide a getfile, since the superclass' does not use this concept."
return self.file
def putheader(self, header, *values):
"The superclass allows only one value argument."
self._conn.putheader(header, '\r\n\t'.join(values))
def getreply(self):
"""Compat definition since superclass does not define it.
Returns a tuple consisting of:
- server status code (e.g. '200' if all goes well)
- server "reason" corresponding to status code
- any RFC822 headers in the response from the server
"""
try:
response = self._conn.getresponse()
except BadStatusLine, e:
### hmm. if getresponse() ever closes the socket on a bad request,
### then we are going to have problems with self.sock
### should we keep this behavior? do people use it?
# keep the socket open (as a file), and return it
self.file = self._conn.sock.makefile('rb', 0)
# close our socket -- we want to restart after any protocol error
self.close()
self.headers = None
return -1, e.line, None
self.headers = response.msg
self.file = response.fp
return response.status, response.reason, response.msg
def close(self):
self._conn.close()
# note that self.file == response.fp, which gets closed by the
# superclass. just clear the object ref here.
### hmm. messy. if status==-1, then self.file is owned by us.
### well... we aren't explicitly closing, but losing this ref will
### do it
self.file = None
if hasattr(socket, 'ssl'):
class HTTPS(HTTP):
"""Compatibility with 1.5 httplib interface
Python 1.5.2 did not have an HTTPS class, but it defined an
interface for sending http requests that is also useful for
https.
"""
_connection_class = HTTPSConnection
def __init__(self, host='', port=None, key_file=None, cert_file=None,
strict=None):
# provide a default host, pass the X509 cert info
# urf. compensate for bad input.
if port == 0:
port = None
self._setup(self._connection_class(host, port, key_file,
cert_file, strict))
# we never actually use these for anything, but we keep them
# here for compatibility with post-1.5.2 CVS.
self.key_file = key_file
self.cert_file = cert_file
class HTTPException(Exception):
# Subclasses that define an __init__ must call Exception.__init__
# or define self.args. Otherwise, str() will fail.
pass
class NotConnected(HTTPException):
pass
class InvalidURL(HTTPException):
pass
class UnknownProtocol(HTTPException):
def __init__(self, version):
self.args = version,
self.version = version
class UnknownTransferEncoding(HTTPException):
pass
class UnimplementedFileMode(HTTPException):
pass
class IncompleteRead(HTTPException):
def __init__(self, partial):
self.args = partial,
self.partial = partial
class ImproperConnectionState(HTTPException):
pass
class CannotSendRequest(ImproperConnectionState):
pass
class CannotSendHeader(ImproperConnectionState):
pass
class ResponseNotReady(ImproperConnectionState):
pass
class BadStatusLine(HTTPException):
def __init__(self, line):
self.args = line,
self.line = line
# for backwards compatibility
error = HTTPException
class LineAndFileWrapper:
"""A limited file-like object for HTTP/0.9 responses."""
# The status-line parsing code calls readline(), which normally
# get the HTTP status line. For a 0.9 response, however, this is
# actually the first line of the body! Clients need to get a
# readable file object that contains that line.
def __init__(self, line, file):
self._line = line
self._file = file
self._line_consumed = 0
self._line_offset = 0
self._line_left = len(line)
def __getattr__(self, attr):
return getattr(self._file, attr)
def _done(self):
# called when the last byte is read from the line. After the
# call, all read methods are delegated to the underlying file
# obhect.
self._line_consumed = 1
self.read = self._file.read
self.readline = self._file.readline
self.readlines = self._file.readlines
def read(self, amt=None):
assert not self._line_consumed and self._line_left
if amt is None or amt > self._line_left:
s = self._line[self._line_offset:]
self._done()
if amt is None:
return s + self._file.read()
else:
return s + self._file.read(amt - len(s))
else:
assert amt <= self._line_left
i = self._line_offset
j = i + amt
s = self._line[i:j]
self._line_offset = j
self._line_left -= amt
if self._line_left == 0:
self._done()
return s
def readline(self):
s = self._line[self._line_offset:]
self._done()
return s
def readlines(self, size=None):
L = [self._line[self._line_offset:]]
self._done()
if size is None:
return L + self._file.readlines()
else:
return L + self._file.readlines(size)
def test():
"""Test this module.
A hodge podge of tests collected here, because they have too many
external dependencies for the regular test suite.
"""
import sys
import getopt
opts, args = getopt.getopt(sys.argv[1:], 'd')
dl = 0
for o, a in opts:
if o == '-d': dl = dl + 1
host = 'www.python.org'
selector = '/'
if args[0:]: host = args[0]
if args[1:]: selector = args[1]
h = HTTP()
h.set_debuglevel(dl)
h.connect(host)
h.putrequest('GET', selector)
h.endheaders()
status, reason, headers = h.getreply()
print 'status =', status
print 'reason =', reason
print "read", len(h.getfile().read())
print
if headers:
for header in headers.headers: print header.strip()
print
# minimal test that code to extract host from url works
class HTTP11(HTTP):
_http_vsn = 11
_http_vsn_str = 'HTTP/1.1'
h = HTTP11('www.python.org')
h.putrequest('GET', 'http://www.python.org/~jeremy/')
h.endheaders()
h.getreply()
h.close()
if hasattr(socket, 'ssl'):
for host, selector in (('sourceforge.net', '/projects/python'),
('dbserv2.theopalgroup.com', '/mediumfile'),
('dbserv2.theopalgroup.com', '/smallfile'),
):
print "https://%s%s" % (host, selector)
hs = HTTPS()
hs.set_debuglevel(dl)
hs.connect(host)
hs.putrequest('GET', selector)
hs.endheaders()
status, reason, headers = hs.getreply()
print 'status =', status
print 'reason =', reason
print "read", len(hs.getfile().read())
print
if headers:
for header in headers.headers: print header.strip()
print
# Test a buggy server -- returns garbled status line.
# http://www.yahoo.com/promotions/mom_com97/supermom.html
c = HTTPConnection("promotions.yahoo.com")
c.set_debuglevel(1)
c.connect()
c.request("GET", "/promotions/mom_com97/supermom.html")
r = c.getresponse()
print r.status, r.version
lines = r.read().split("\n")
print "\n".join(lines[:5])
c = HTTPConnection("promotions.yahoo.com", strict=1)
c.set_debuglevel(1)
c.connect()
c.request("GET", "/promotions/mom_com97/supermom.html")
try:
r = c.getresponse()
except BadStatusLine, err:
print "strict mode failed as expected"
print err
else:
print "XXX strict mode should have failed"
for strict in 0, 1:
h = HTTP(strict=strict)
h.connect("promotions.yahoo.com")
h.putrequest('GET', "/promotions/mom_com97/supermom.html")
h.endheaders()
status, reason, headers = h.getreply()
assert (strict and status == -1) or status == 200, (strict, status)
if __name__ == '__main__':
test()