smtplib.py

mallet是自然语言处理、机器学习领域的一个开源项目。

#! /usr/bin/env python

'''SMTP/ESMTP client class.

This should follow RFC 821 (SMTP), RFC 1869 (ESMTP), RFC 2554 (SMTP
Authentication) and RFC 2487 (Secure SMTP over TLS).

Notes:

Please remember, when doing ESMTP, that the names of the SMTP service
extensions are NOT the same thing as the option keywords for the RCPT
and MAIL commands!

Example:

  >>> import smtplib
  >>> s=smtplib.SMTP("localhost")
  >>> print s.help()
  This is Sendmail version 8.8.4
  Topics:
      HELO    EHLO    MAIL    RCPT    DATA
      RSET    NOOP    QUIT    HELP    VRFY
      EXPN    VERB    ETRN    DSN
  For more info use "HELP <topic>".
  To report bugs in the implementation send email to
      [e-mail].
  For local information send email to Postmaster at your site.
  End of HELP info
  >>> s.putcmd("vrfy","someone@here")
  >>> s.getreply()
  (250, "Somebody OverHere <[e-mail]>")
  >>> s.quit()
'''

# Author: The Dragon De Monsyne <[e-mail]>
# ESMTP support, test code and doc fixes added by
#     Eric S. Raymond <[e-mail]>
# Better RFC 821 compliance (MAIL and RCPT, and CRLF in data)
#     by Carey Evans <[e-mail]>, for picky mail servers.
# RFC 2554 (authentication) support by Gerhard Haering <[e-mail]>.
#
# This was modified from the Python 1.5 library HTTP lib.

import socket
import re
import rfc822
import types
import base64
import hmac

__all__ = ["SMTPException","SMTPServerDisconnected","SMTPResponseException",
           "SMTPSenderRefused","SMTPRecipientsRefused","SMTPDataError",
           "SMTPConnectError","SMTPHeloError","SMTPAuthenticationError",
           "quoteaddr","quotedata","SMTP"]

SMTP_PORT = 25
CRLF="\r\n"

OLDSTYLE_AUTH = re.compile(r"auth=(.*)", re.I)

def encode_base64(s, eol=None):
    return "".join(base64.encodestring(s).split("\n"))

# Exception classes used by this module.
class SMTPException(Exception):
    """Base class for all exceptions raised by this module."""

class SMTPServerDisconnected(SMTPException):
    """Not connected to any SMTP server.

    This exception is raised when the server unexpectedly disconnects,
    or when an attempt is made to use the SMTP instance before
    connecting it to a server.
    """

class SMTPResponseException(SMTPException):
    """Base class for all exceptions that include an SMTP error code.

    These exceptions are generated in some instances when the SMTP
    server returns an error code.  The error code is stored in the
    `smtp_code' attribute of the error, and the `smtp_error' attribute
    is set to the error message.
    """

    def __init__(self, code, msg):
        self.smtp_code = code
        self.smtp_error = msg
        self.args = (code, msg)

class SMTPSenderRefused(SMTPResponseException):
    """Sender address refused.

    In addition to the attributes set by on all SMTPResponseException
    exceptions, this sets `sender' to the string that the SMTP refused.
    """

    def __init__(self, code, msg, sender):
        self.smtp_code = code
        self.smtp_error = msg
        self.sender = sender
        self.args = (code, msg, sender)

class SMTPRecipientsRefused(SMTPException):
    """All recipient addresses refused.

    The errors for each recipient are accessible through the attribute
    'recipients', which is a dictionary of exactly the same sort as
    SMTP.sendmail() returns.
    """

    def __init__(self, recipients):
        self.recipients = recipients
        self.args = ( recipients,)


class SMTPDataError(SMTPResponseException):
    """The SMTP server didn't accept the data."""

class SMTPConnectError(SMTPResponseException):
    """Error during connection establishment."""

class SMTPHeloError(SMTPResponseException):
    """The server refused our HELO reply."""

class SMTPAuthenticationError(SMTPResponseException):
    """Authentication error.

    Most probably the server didn't accept the username/password
    combination provided.
    """

class SSLFakeSocket:
    """A fake socket object that really wraps a SSLObject.

    It only supports what is needed in smtplib.
    """
    def __init__(self, realsock, sslobj):
        self.realsock = realsock
        self.sslobj = sslobj

    def send(self, str):
        self.sslobj.write(str)
        return len(str)

    sendall = send

    def close(self):
        self.realsock.close()

class SSLFakeFile:
    """A fake file like object that really wraps a SSLObject.

    It only supports what is needed in smtplib.
    """
    def __init__( self, sslobj):
        self.sslobj = sslobj

    def readline(self):
        str = ""
        chr = None
        while chr != "\n":
            chr = self.sslobj.read(1)
            str += chr
        return str

    def close(self):
        pass

def quoteaddr(addr):
    """Quote a subset of the email addresses defined by RFC 821.

    Should be able to handle anything rfc822.parseaddr can handle.
    """
    m = (None, None)
    try:
        m=rfc822.parseaddr(addr)[1]
    except AttributeError:
        pass
    if m == (None, None): # Indicates parse failure or AttributeError
        #something weird here.. punt -ddm
        return "<%s>" % addr
    else:
        return "<%s>" % m

def quotedata(data):
    """Quote data for email.

    Double leading '.', and change Unix newline '\\n', or Mac '\\r' into
    Internet CRLF end-of-line.
    """
    return re.sub(r'(?m)^\.', '..',
        re.sub(r'(?:\r\n|\n|\r(?!\n))', CRLF, data))


class SMTP:
    """This class manages a connection to an SMTP or ESMTP server.
    SMTP Objects:
        SMTP objects have the following attributes:
            helo_resp
                This is the message given by the server in response to the
                most recent HELO command.

            ehlo_resp
                This is the message given by the server in response to the
                most recent EHLO command. This is usually multiline.

            does_esmtp
                This is a True value _after you do an EHLO command_, if the
                server supports ESMTP.

            esmtp_features
                This is a dictionary, which, if the server supports ESMTP,
                will _after you do an EHLO command_, contain the names of the
                SMTP service extensions this server supports, and their
                parameters (if any).

                Note, all extension names are mapped to lower case in the
                dictionary.

        See each method's docstrings for details.  In general, there is a
        method of the same name to perform each SMTP command.  There is also a
        method called 'sendmail' that will do an entire mail transaction.
        """
    debuglevel = 0
    file = None
    helo_resp = None
    ehlo_resp = None
    does_esmtp = 0

    def __init__(self, host = '', port = 0):
        """Initialize a new instance.

        If specified, `host' is the name of the remote host to which to
        connect.  If specified, `port' specifies the port to which to connect.
        By default, smtplib.SMTP_PORT is used.  An SMTPConnectError is raised
        if the specified `host' doesn't respond correctly.

        """
        self.esmtp_features = {}
        if host:
            (code, msg) = self.connect(host, port)
            if code != 220:
                raise SMTPConnectError(code, msg)

    def set_debuglevel(self, debuglevel):
        """Set the debug output level.

        A non-false value results in debug messages for connection and for all
        messages sent to and received from the server.

        """
        self.debuglevel = debuglevel

    def connect(self, host='localhost', port = 0):
        """Connect to a host on a given port.

        If the hostname ends with a colon (`:') followed by a number, and
        there is no port specified, that suffix will be stripped off and the
        number interpreted as the port number to use.

        Note: This method is automatically invoked by __init__, if a host is
        specified during instantiation.

        """
        if not port and (host.find(':') == host.rfind(':')):
            i = host.rfind(':')
            if i >= 0:
                host, port = host[:i], host[i+1:]
                try: port = int(port)
                except ValueError:
                    raise socket.error, "nonnumeric port"
        if not port: port = SMTP_PORT
        if self.debuglevel > 0: print 'connect:', (host, port)
        msg = "getaddrinfo returns an empty list"
        self.sock = None
        for res in socket.getaddrinfo(host, 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:', (host, port)
                self.sock.connect(sa)
            except socket.error, msg:
                if self.debuglevel > 0: print 'connect fail:', (host, port)
                if self.sock:
                    self.sock.close()
                self.sock = None
                continue
            break
        if not self.sock:
            raise socket.error, msg
        (code, msg) = self.getreply()
        if self.debuglevel > 0: print "connect:", msg
        return (code, msg)

    def send(self, str):
        """Send `str' to the server."""
        if self.debuglevel > 0: print 'send:', `str`
        if self.sock:
            try:
                self.sock.sendall(str)
            except socket.error:
                self.close()
                raise SMTPServerDisconnected('Server not connected')
        else:
            raise SMTPServerDisconnected('please run connect() first')

    def putcmd(self, cmd, args=""):
        """Send a command to the server."""
        if args == "":
            str = '%s%s' % (cmd, CRLF)
        else:
            str = '%s %s%s' % (cmd, args, CRLF)
        self.send(str)

    def getreply(self):
        """Get a reply from the server.

        Returns a tuple consisting of:

          - server response code (e.g. '250', or such, if all goes well)
            Note: returns -1 if it can't read response code.

          - server response string corresponding to response code (multiline
            responses are converted to a single, multiline string).

        Raises SMTPServerDisconnected if end-of-file is reached.
        """
        resp=[]
        if self.file is None:
            self.file = self.sock.makefile('rb')
        while 1:
            line = self.file.readline()
            if line == '':
                self.close()
                raise SMTPServerDisconnected("Connection unexpectedly closed")
            if self.debuglevel > 0: print 'reply:', `line`
            resp.append(line[4:].strip())
            code=line[:3]
            # Check that the error code is syntactically correct.
            # Don't attempt to read a continuation line if it is broken.
            try:
                errcode = int(code)
            except ValueError:
                errcode = -1
                break
            # Check if multiline response.
            if line[3:4]!="-":
                break

        errmsg = "\n".join(resp)
        if self.debuglevel > 0:
            print 'reply: retcode (%s); Msg: %s' % (errcode,errmsg)
        return errcode, errmsg

    def docmd(self, cmd, args=""):
        """Send a command, and return its response code."""
        self.putcmd(cmd,args)
        return self.getreply()

    # std smtp commands
    def helo(self, name=''):
        """SMTP 'helo' command.
        Hostname to send for this command defaults to the FQDN of the local
        host.
        """