Python Network Programming Resources

Python Network - POP3

Quiz

The pop3 protocol is an email protocol to download messages from the email-server. These messages can be stored in the local machine.

Key Points

POP is an application layer internet standard protocol.
Since POP supports offline access to the messages, thus requires less internet usage time.
POP does not allow search facility.
In order to access the messaged, it is necessary to download them.
It allows only one mailbox to be created on server.
It is not suitable for accessing non mail data.
POP commands are generally abbreviated into codes of three or four letters. Eg. STAT.

POP Commands

The following table describes some of the POP commands:

S.N.	Command Description
1	LOGIN This command opens the connection.
2	STAT It is used to display number of messages currently in the mailbox.
3	LIST It is used to get the summary of messages where each message summary is shown.
4	RETR This command helps to select a mailbox to access the messages.
5	DELE It is used to delete a message.
6	RSET It is used to reset the session to its initial state.
7	QUIT It is used to log off the session.

Example - Using POP3 with Gmail

Pyhtons poplib module provides classes named pop() and pop3_SSL() which are used to achieve this requirement. We supply the hostname and port number as argument. In the below example we connect to a gmail server and retrieve the messages after supplying the login credentials.

main.py

import  poplib

user = 'username' 
# Connect to the mail box 
Mailbox = poplib.POP3_SSL('pop.googlemail.com', '995') 
Mailbox.user(user) 
Mailbox.pass_('password') 
NumofMessages = len(Mailbox.list()[1])
for i in range(NumofMessages):
    for msg in Mailbox.retr(i+1)[1]:
        print msg
Mailbox.quit()

The messages are retrieved when the above program is run.

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