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Python and Gmail with IMAP

Today I had to automatically access my Gmail inbox from Python. I needed the ability to get an unread email count, the subjects of those unread emails and then download them. I found a Gmail.py library on sourceforge, but it actually opened the normal gmail webpage and site scraped the info. I wanted something much faster, luckily gmail can now be accessed with both pop and imap.

After a tiny amount of research I decided imap was the better albiet slightly more difficult protocol. Enabling imap in gmail is straight forward, it was under labs.

The address for gmail's imap server is:

imap.gmail.com:993

Python has a library module called imaplib, we will make heavy use of that to access our emails. I'm going to assume that we have already defined two globals - username and password. To connect and login to the gmail server and select the inbox we can do:

import imaplib

imap_server = imaplib.IMAP4_SSL("imap.gmail.com",993)
imap_server.login(username, password)

imap_server.select('INBOX')

All pretty straight forward so far, lets find out how many unread emails we have:

# Count the unread emails
status, response = imap_server.status('INBOX', "(UNSEEN)")
unreadcount = int(response[0].split()[2].strip(').,]'))
print unreadcount

Now I'm not saying this is a particularly nice way of doing this, but if you print the response and reverse engineer it you will see how I arrived with that string parsing. Regex would be another option, but I try avoid that unless it is required. Now lets get a list of the identifiers for each unread message, I'm going to call it email_ids:

# Search for all new mail
status, email_ids = imap_server.search(None, '(UNSEEN)')
print email_ids

If I want to download a particular list of messages, or maybe download the subjects for a list of messages I can use the following functions:

def get_emails(email_ids):
    data = []
    for e_id in email_ids:
        _, response = imap_server.fetch(e_id, '(UID BODY[TEXT])')
        data.append(response[0][1])
    return data

def get_subjects(email_ids):
    subjects = []
    for e_id in email_ids:
        _, response = imap_server.fetch(e_id, '(body[header.fields (subject)])')
        subjects.append( response[0][1][9:] )
    return subjects

And I often search for emails from someone in particular, I can do that easily from Python as well:

def emails_from(name):
    '''Search for all mail from name'''
    status, response = imap_server.search(None, '(FROM "%s")' % name)
    email_ids = [e_id for e_id in response[0].split()]
    print 'Number of emails from %s: %i. IDs: %s' % (name, len(email_ids), email_ids)
    return email_ids

Now this can all be combined to print the body of the latest 3 emails sent by my friend bob:

for email in get_emails(emails_from("bob")[-3:-1]):
    print email

Thats all folks!

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