smtpd
— SMTP (简单邮件传输协议) 服务器
¶
源代码： Lib/smtpd.py
此模块提供实现 SMTP (电子邮件) 服务器的几个类。
存在几种服务器实现；一个是可以覆盖且什么都不做的一般实现，而其它 2 个提供特定邮件发送战略。
此外，可以扩展 SMTPChannel 以实现非常具体的交互行为采用 SMTP (简单邮件传输协议) 客户端。
代码支持 RFC 5321 ，加 RFC 1870 SIZE extension.
smtpd.
SMTPServer
(
localaddr
,
remoteaddr
,
data_size_limit=33554432
,
map=None
)
¶
创建新的
SMTPServer
对象，绑定到本地地址
localaddr
。它将视
remoteaddr
as an upstream SMTP relayer. It inherits from
asyncore.dispatcher
，且因此将自身插入
asyncore
‘s event loop on instantiation.
data_size_limit
指定将接受的最大字节数在
DATA
命令。值为
None
or
0
意味着没有限制。
A dictionary can be specified in map to avoid using a global socket map.
process_message
(
peer
,
mailfrom
,
rcpttos
,
data
)
¶
引发
NotImplementedError
exception. Override this in subclasses to do something useful with this message. Whatever was passed in the constructor as
remoteaddr
will be available as the
_remoteaddr
属性。
peer
是远程主机的地址，
mailfrom
是信封发起人，
rcpttos
are the envelope recipients and
data
is a string containing the contents of the e-mail (which should be in
RFC 2822
格式)。
channel_class
¶
在子类中覆盖此以使用自定义
SMTPChannel
为管理 SMTP (简单邮件传输协议) 客户端。
3.4 版改变： The map 自变量被添加。
smtpd.
DebuggingServer
(
localaddr
,
remoteaddr
)
¶
Create a new debugging server. Arguments are as per
SMTPServer
. Messages will be discarded, and printed on stdout.
smtpd.
PureProxy
(
localaddr
,
remoteaddr
)
¶
Create a new pure proxy server. Arguments are as per
SMTPServer
. Everything will be relayed to
remoteaddr
. Note that running this has a good chance to make you into an open relay, so please be careful.
smtpd.
MailmanProxy
(
localaddr
,
remoteaddr
)
¶
Create a new pure proxy server. Arguments are as per
SMTPServer
. Everything will be relayed to
remoteaddr
, unless local mailman configurations knows about an address, in which case it will be handled via mailman. Note that running this has a good chance to make you into an open relay, so please be careful.
smtpd.
SMTPChannel
(
server
,
conn
,
addr
,
data_size_limit=33554432
,
map=None)
)
¶
创建新的
SMTPChannel
object which manages the communication between the server and a single SMTP client.
conn and addr are as per the instance variables described below.
data_size_limit
指定将接受的最大字节数在
DATA
命令。值为
None
or
0
意味着没有限制。
A dictionary can be specified in map to avoid using a global socket map.
To use a custom SMTPChannel implementation you need to override the
SMTPServer.channel_class
of your
SMTPServer
.
The
SMTPChannel
拥有下列实例变量：
smtp_server
¶
保持
SMTPServer
卵生此通道。
conn
¶
保存连接到客户端的套接字对象。
addr
¶
Holds the address of the client, the second value returned by
socket.accept
received_lines
¶
Holds a list of the line strings (decoded using UTF-8) received from the client. The lines have their
"\r\n"
line ending translated to
"\n"
.
smtp_state
¶
Holds the current state of the channel. This will be either
COMMAND
initially and then
DATA
after the client sends a “DATA” line.
seen_greeting
¶
Holds a string containing the greeting sent by the client in its “HELO”.
mailfrom
¶
Holds a string containing the address identified in the “MAIL FROM:” line from the client.
rcpttos
¶
Holds a list of strings containing the addresses identified in the “RCPT TO:” lines from the client.
received_data
¶
Holds a string containing all of the data sent by the client during the DATA state, up to but not including the terminating
"\r\n.\r\n"
.
fqdn
¶
Holds the fully-qualified domain name of the server as returned by
socket.getfqdn()
.
The
SMTPChannel
operates by invoking methods named
smtp_<command>
upon reception of a command line from the client. Built into the base
SMTPChannel
class are methods for handling the following commands (and responding to them appropriately):
| 命令 | Action taken |
|---|---|
| HELO |
Accepts the greeting from the client and stores it in
seen_greeting
. Sets server to base command mode.
|
| EHLO |
Accepts the greeting from the client and stores it in
seen_greeting
. Sets server to extended command mode.
|
| NOOP | Takes no action. |
| QUIT | 干净地关闭连接。 |
Accepts the “MAIL FROM:” syntax and stores the supplied address as
mailfrom
. In extended command mode, accepts the
RFC 1870
SIZE attribute and responds appropriately based on the
value of
data_size_limit
.
|
|
| RCPT |
Accepts the “RCPT TO:” syntax and stores the supplied addresses in
the
rcpttos
列表。
|
| RSET |
重置
mailfrom
,
rcpttos
，和
received_data
，但不问候。
|
| DATA |
Sets the internal state to
DATA
and stores remaining lines
from the client in
received_data
until the terminator
"\r\n.\r\n"
is received.
|
| HELP | Returns minimal information on command syntax |
| VRFY | Returns code 252 (the server doesn’t know if the address is valid) |
| EXPN | Reports that the command is not implemented. |