"""HTTP/1.1 client library



<intro stuff goes here>

<other stuff, too>



HTTPConnection goes through a number of "states", which define 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>

"""



from array import array

import socket

from sys import py3kwarning

from urlparse import urlsplit

import warnings

with warnings.catch_warnings():

    if py3kwarning:

        warnings.filterwarnings("ignore", ".*mimetools has been removed",

                                DeprecationWarning)

    import mimetools



try:

    from cStringIO import StringIO

except ImportError:

    from StringIO import StringIO



__all__ = ["HTTP", "HTTPResponse", "HTTPConnection",

           "HTTPException", "NotConnected", "UnknownProtocol",

           "UnknownTransferEncoding", "UnimplementedFileMode",

           "IncompleteRead", "InvalidURL", "ImproperConnectionState",

           "CannotSendRequest", "CannotSendHeader", "ResponseNotReady",

           "BadStatusLine", "error", "responses"]



HTTP_PORT = 80

HTTPS_PORT = 443



_UNKNOWN = 'UNKNOWN'



# connection states

_CS_IDLE = 'Idle'

_CS_REQ_STARTED = 'Request-started'

_CS_REQ_SENT = 'Request-sent'



# status codes

# informational

CONTINUE = 100

SWITCHING_PROTOCOLS = 101

PROCESSING = 102



# successful

OK = 200

CREATED = 201

ACCEPTED = 202

NON_AUTHORITATIVE_INFORMATION = 203

NO_CONTENT = 204

RESET_CONTENT = 205

PARTIAL_CONTENT = 206

MULTI_STATUS = 207

IM_USED = 226



# redirection

MULTIPLE_CHOICES = 300

MOVED_PERMANENTLY = 301

FOUND = 302

SEE_OTHER = 303

NOT_MODIFIED = 304

USE_PROXY = 305

TEMPORARY_REDIRECT = 307



# client error

BAD_REQUEST = 400

UNAUTHORIZED = 401

PAYMENT_REQUIRED = 402

FORBIDDEN = 403

NOT_FOUND = 404

METHOD_NOT_ALLOWED = 405

NOT_ACCEPTABLE = 406

PROXY_AUTHENTICATION_REQUIRED = 407

REQUEST_TIMEOUT = 408

CONFLICT = 409

GONE = 410

LENGTH_REQUIRED = 411

PRECONDITION_FAILED = 412

REQUEST_ENTITY_TOO_LARGE = 413

REQUEST_URI_TOO_LONG = 414

UNSUPPORTED_MEDIA_TYPE = 415

REQUESTED_RANGE_NOT_SATISFIABLE = 416

EXPECTATION_FAILED = 417

UNPROCESSABLE_ENTITY = 422

LOCKED = 423

FAILED_DEPENDENCY = 424

UPGRADE_REQUIRED = 426



# server error

INTERNAL_SERVER_ERROR = 500

NOT_IMPLEMENTED = 501

BAD_GATEWAY = 502

SERVICE_UNAVAILABLE = 503

GATEWAY_TIMEOUT = 504

HTTP_VERSION_NOT_SUPPORTED = 505

INSUFFICIENT_STORAGE = 507

NOT_EXTENDED = 510



# Mapping status codes to official W3C names

responses = {

    100: 'Continue',

    101: 'Switching Protocols',



    200: 'OK',

    201: 'Created',

    202: 'Accepted',

    203: 'Non-Authoritative Information',

    204: 'No Content',

    205: 'Reset Content',

    206: 'Partial Content',



    300: 'Multiple Choices',

    301: 'Moved Permanently',

    302: 'Found',

    303: 'See Other',

    304: 'Not Modified',

    305: 'Use Proxy',

    306: '(Unused)',

    307: 'Temporary Redirect',



    400: 'Bad Request',

    401: 'Unauthorized',

    402: 'Payment Required',

    403: 'Forbidden',

    404: 'Not Found',

    405: 'Method Not Allowed',

    406: 'Not Acceptable',

    407: 'Proxy Authentication Required',

    408: 'Request Timeout',

    409: 'Conflict',

    410: 'Gone',

    411: 'Length Required',

    412: 'Precondition Failed',

    413: 'Request Entity Too Large',

    414: 'Request-URI Too Long',

    415: 'Unsupported Media Type',

    416: 'Requested Range Not Satisfiable',

    417: 'Expectation Failed',



    500: 'Internal Server Error',

    501: 'Not Implemented',

    502: 'Bad Gateway',

    503: 'Service Unavailable',

    504: 'Gateway Timeout',

    505: 'HTTP Version Not Supported',

}



# maximal amount of data to read at one time in _safe_read

MAXAMOUNT = 1048576



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 = hlist = []

        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 True:

            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.

                hlist.append(line)

                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.

                hlist.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, method=None):

        self.fp = sock.makefile('rb', 0)

        self.debuglevel = debuglevel

        self.strict = strict

        self._method = method



        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)

        if not line:

            # Presumably, the server closed the connection before

            # sending a valid response.

            raise BadStatusLine(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 True:

            version, status, reason = self._read_status()

            if status != CONTINUE:

                break

            # skip the header from the 100 response

            while True:

                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.length = None

            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?

        self.will_close = self._check_close()



        # 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:

                if self.length < 0:  # ignore nonsensical negative lengths

                    self.length = None

        else:

            self.length = None



        # does the body have a fixed length? (of zero)

        if (status == NO_CONTENT or status == NOT_MODIFIED or

            100 <= status < 200 or      # 1xx codes

            self._method == 'HEAD'):

            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 _check_close(self):

        conn = self.msg.getheader('connection')

        if self.version == 11:

            # An HTTP/1.1 proxy is assumed to stay open unless

            # explicitly closed.

            conn = self.msg.getheader('connection')

            if conn and "close" in conn.lower():

                return True

            return False



        # Some HTTP/1.0 implementations have support for persistent

        # connections, using rules different than HTTP/1.1.



        # For older HTTP, Keep-Alive indicates persistent connection.

        if self.msg.getheader('keep-alive'):

            return False



        # At least Akamai returns a "Connection: Keep-Alive" header,

        # which was supposed to be sent by the client.

        if conn and "keep-alive" in conn.lower():

            return False



        # Proxy-Connection is a netscape hack.

        pconn = self.msg.getheader('proxy-connection')

        if pconn and "keep-alive" in pconn.lower():

            return False



        # otherwise, assume it will close

        return True



    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



    # XXX It would be nice to have readline and __iter__ for this, too.



    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.length is None:

                s = self.fp.read()

            else:

                s = self._safe_read(self.length)

                self.length = 0

            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



        # 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)

        if self.length is not None:

            self.length -= len(s)

            if not self.length:

                self.close()

        return s



    def _read_chunked(self, amt):

        assert self.chunked != _UNKNOWN

        chunk_left = self.chunk_left

        value = []

        while True:

            if chunk_left is None:

                line = self.fp.readline()

                i = line.find(';')

                if i >= 0:

                    line = line[:i] # strip chunk-extensions

                try:

                    chunk_left = int(line, 16)

                except ValueError:

                    # close the connection as protocol synchronisation is

                    # probably lost

                    self.close()

                    raise IncompleteRead(''.join(value))

                if chunk_left == 0:

                    break

            if amt is None:

                value.append(self._safe_read(chunk_left))

            elif amt < chunk_left:

                value.append(self._safe_read(amt))

                self.chunk_left = chunk_left - amt

                return ''.join(value)

            elif amt == chunk_left:

                value.append(self._safe_read(amt))

                self._safe_read(2)  # toss the CRLF at the end of the chunk

                self.chunk_left = None

                return ''.join(value)

            else:

                value.append(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 True:

            line = self.fp.readline()

            if not line:

                # a vanishingly small number of sites EOF without

                # sending the trailer

                break

            if line == '\r\n':

                break



        # we read everything; close the "file"

        self.close()



        return ''.join(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(min(amt, MAXAMOUNT))

            if not chunk:

                raise IncompleteRead(''.join(s), amt)

            s.append(chunk)

            amt -= len(chunk)

        return ''.join(s)



    def getheader(self, name, default=None):

        if self.msg is None:

            raise ResponseNotReady()

        return self.msg.getheader(name, default)



    def getheaders(self):

        """Return list of (header, value) tuples."""

        if self.msg is None:

            raise ResponseNotReady()

        return self.msg.items()





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,

                 timeout=socket._GLOBAL_DEFAULT_TIMEOUT):

        self.timeout = timeout

        self.sock = None

        self._buffer = []

        self.__response = None

        self.__state = _CS_IDLE

        self._method = None

        self._tunnel_host = None

        self._tunnel_port = None



        self._set_hostport(host, port)

        if strict is not None:

            self.strict = strict



    def _set_tunnel(self, host, port=None):

        """ Sets up the host and the port for the HTTP CONNECT Tunnelling."""

        self._tunnel_host = host

        self._tunnel_port = port



    def _set_hostport(self, host, port):

        if port is None:

            i = host.rfind(':')

            j = host.rfind(']')         # ipv6 addresses have [...]

            if i > j:

                try:

                    port = int(host[i+1:])

                except ValueError:

                    raise InvalidURL("nonnumeric port: '%s'" % host[i+1:])

                host = host[:i]

            else:

                port = self.default_port

            if host and host[0] == '[' and host[-1] == ']':

                host = host[1:-1]

        self.host = host

        self.port = port



    def set_debuglevel(self, level):

        self.debuglevel = level



    def _tunnel(self):

        self._set_hostport(self._tunnel_host, self._tunnel_port)

        self.send("CONNECT %s:%d HTTP/1.0\r\n\r\n" % (self.host, self.port))

        response = self.response_class(self.sock, strict = self.strict,

                                       method = self._method)

        (version, code, message) = response._read_status()



        if code != 200:

            self.close()

            raise socket.error, "Tunnel connection failed: %d %s" % (code,

                                                                     message.strip())

        while True:

            line = response.fp.readline()

            if line == '\r\n': break





    def connect(self):

        """Connect to the host and port specified in __init__."""

        self.sock = socket.create_connection((self.host,self.port),

                                             self.timeout)



        if self._tunnel_host:

            self._tunnel()



    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:

            blocksize=8192

            if hasattr(str,'read') and not isinstance(str, array):

                if self.debuglevel > 0: print "sendIng a read()able"

                data=str.read(blocksize)

                while data:

                    self.sock.sendall(data)

                    data=str.read(blocksize)

            else:

                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, skip_accept_encoding=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'.

        `skip_host' if True does not add automatically a 'Host:' header

        `skip_accept_encoding' if True does not add automatically an

           'Accept-Encoding:' header

        """



        # if a prior response has been completed, then forget about it.

        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()



        # Save the method we use, we need it later in the response phase

        self._method = method

        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:

                    try:

                        netloc_enc = netloc.encode("ascii")

                    except UnicodeEncodeError:

                        netloc_enc = netloc.encode("idna")

                    self.putheader('Host', netloc_enc)

                else:

                    try:

                        host_enc = self.host.encode("ascii")

                    except UnicodeEncodeError:

                        host_enc = self.host.encode("idna")

                    if self.port == self.default_port:

                        self.putheader('Host', host_enc)

                    else:

                        self.putheader('Host', "%s:%s" % (host_enc, 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.

            if not skip_accept_encoding:

                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):

        # honour explicitly requested Host: and Accept-Encoding headers

        header_names = dict.fromkeys([k.lower() for k in headers])

        skips = {}

        if 'host' in header_names:

            skips['skip_host'] = 1

        if 'accept-encoding' in header_names:

            skips['skip_accept_encoding'] = 1



        self.putrequest(method, url, **skips)



        if body and ('content-length' not in header_names):

            thelen=None

            try:

                thelen=str(len(body))

            except TypeError, te:

                # If this is a file-like object, try to

                # fstat its file descriptor

                import os

                try:

                    thelen = str(os.fstat(body.fileno()).st_size)

                except (AttributeError, OSError):

                    # Don't send a length if this failed

                    if self.debuglevel > 0: print "Cannot stat!!"



            if thelen is not None:

                self.putheader('Content-Length',thelen)

        for hdr, value in headers.iteritems():

            self.putheader(hdr, value)

        self.endheaders()



        if body:

            self.send(body)



    def getresponse(self):

        "Get the response from the server."



        # if a prior response has been completed, then forget about it.

        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,

                                           method=self._method)

        else:

            response = self.response_class(self.sock, strict=self.strict,

                                           method=self._method)



        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





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



try:

    import ssl

except ImportError:

    pass

else:

    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, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):

            HTTPConnection.__init__(self, host, port, strict, timeout)

            self.key_file = key_file

            self.cert_file = cert_file



        def connect(self):

            "Connect to a host on a given (SSL) port."



            sock = socket.create_connection((self.host, self.port), self.timeout)

            if self._tunnel_host:

                self.sock = sock

                self._tunnel()

            self.sock = ssl.wrap_socket(sock, self.key_file, self.cert_file)



    __all__.append("HTTPSConnection")



    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





    def FakeSocket (sock, sslobj):

        warnings.warn("FakeSocket is deprecated, and won't be in 3.x.  " +

                      "Use the result of ssl.wrap_socket() directly instead.",

                      DeprecationWarning, stacklevel=2)

        return sslobj





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, expected=None):

        self.args = partial,

        self.partial = partial

        self.expected = expected

    def __repr__(self):

        if self.expected is not None:

            e = ', %i more expected' % self.expected

        else:

            e = ''

        return 'IncompleteRead(%i bytes read%s)' % (len(self.partial), e)

    def __str__(self):

        return repr(self)



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

        # object.

        self._line_consumed = 1

        self.read = self._file.read

        self.readline = self._file.readline

        self.readlines = self._file.readlines



    def read(self, amt=None):

        if self._line_consumed:

            return self._file.read(amt)

        assert 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):

        if self._line_consumed:

            return self._file.readline()

        assert self._line_left

        s = self._line[self._line_offset:]

        self._done()

        return s



    def readlines(self, size=None):

        if self._line_consumed:

            return self._file.readlines(size)

        assert self._line_left

        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()



    try:

        import ssl

    except ImportError:

        pass

    else:



        for host, selector in (('sourceforge.net', '/projects/python'),

                               ):

            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



if __name__ == '__main__':

    test()

