SMTP Objects
------------
An `SMTP' instance has the following methods:
`set_debuglevel(level)'
Set the debug output level. A true value for LEVEL results in
debug messages for connection and for all messages sent to and
received from the server.
`connect([host[, port]])'
Connect to a host on a given port. The defaults are to connect to
the local host at the standard SMTP port (25).
If the hostname ends with a colon (`:') followed by a number, that
suffix will be stripped off and the number interpreted as the port
number to use.
Note: This method is automatically invoked by the constructor if a
host is specified during instantiation.
`docmd(cmd, [, argstring])'
Send a command CMD to the server. The optional argument ARGSTRING
is simply concatenated to the command, separated by a space.
This returns a 2-tuple composed of a numeric response code and the
actual response line (multiline responses are joined into one long
line.)
In normal operation it should not be necessary to call this method
explicitly. It is used to implement other methods and may be
useful for testing private extensions.
If the connection to the server is lost while waiting for the
reply, `SMTPServerDisconnected' will be raised.
`helo([hostname])'
Identify yourself to the SMTP server using `HELO'. The hostname
argument defaults to the fully qualified domain name of the local
host.
In normal operation it should not be necessary to call this method
explicitly. It will be implicitly called by the `sendmail()' when
necessary.
`ehlo([hostname])'
Identify yourself to an ESMTP server using `EHLO'. The hostname
argument defaults to the fully qualified domain name of the local
host. Examine the response for ESMTP option and store them for
use by `has_option()'.
Unless you wish to use `has_option()' before sending mail, it
should not be necessary to call this method explicitly. It will
be implicitly called by `sendmail()' when necessary.
`has_extn(name)'
Return `1' if NAME is in the set of SMTP service extensions
returned by the server, `0' otherwise. Case is ignored.
`verify(address)'
Check the validity of an address on this server using SMTP `VRFY'.
Returns a tuple consisting of code 250 and a full RFC 822 address
(including human name) if the user address is valid. Otherwise
returns an SMTP error code of 400 or greater and an error string.
Note: many sites disable SMTP `VRFY' in order to foil spammers.
`sendmail(from_addr, to_addrs, msg[, mail_options, rcpt_options])'
Send mail. The required arguments are an RFC 822 from-address
string, a list of RFC 822 to-address strings, and a message string.
The caller may pass a list of ESMTP options (such as `8bitmime')
to be used in `MAIL FROM' commands as MAIL_OPTIONS. ESMTP options
(such as `DSN' commands) that should be used with all `RCPT'
commands can be passed as RCPT_OPTIONS. (If you need to use
different ESMTP options to different recipients you have to use
the low-level methods such as `mail', `rcpt' and `data' to send
the message.)
*Note:* The FROM_ADDR and TO_ADDRS parameters are used to
construct the message envelope used by the transport agents. The
`SMTP' does not modify the message headers in any way.
If there has been no previous `EHLO' or `HELO' command this
session, this method tries ESMTP `EHLO' first. If the server does
ESMTP, message size and each of the specified options will be
passed to it (if the option is in the feature set the server
advertises). If `EHLO' fails, `HELO' will be tried and ESMTP
options suppressed.
This method will return normally if the mail is accepted for at
least one recipient. Otherwise it will throw an exception. That
is, if this method does not throw an exception, then someone
should get your mail. If this method does not throw an exception,
it returns a dictionary, with one entry for each recipient that
was refused. Each entry contains a tuple of the SMTP error code
and the accompanying error message sent by the server.
This method may raise the following exceptions:
``SMTPRecipientsRefused''
All recipients were refused. Nobody got the mail. The
`recipients' attribute of the exception object is a dictionary
with information about the refused recipients (like the one
returned when at least one recipient was accepted).
``SMTPHeloError''
The server didn't reply properly to the `HELO' greeting.
``SMTPSenderRefused''
The server didn't accept the FROM_ADDR.
``SMTPDataError''
The server replied with an unexpected error code (other than
a refusal of a recipient).
Unless otherwise noted, the connection will be open even after an
exception is raised.
`quit()'
Terminate the SMTP session and close the connection.
Low-level methods corresponding to the standard SMTP/ESMTP commands
`HELP', `RSET', `NOOP', `MAIL', `RCPT', and `DATA' are also supported.
Normally these do not need to be called directly, so they are not
documented here. For details, consult the module code.