Mail bot sript that sends predefined response to predefined mails. Intended for raspberry pi, which has its dedicated mail id

mailbot.py

# mailbot.py
# python 2.7.6

"""
Mail bot sript that sends predefined response to predefined mails
Intended for raspberry pi, which has its dedicated mail id

Algorithm
1) Check a dedicated mailbox inbox for "unread" mails
2) For each "unread" mail, fetch the sender, subject and content
3) If the sender is from a pre-approved list, proceed
4) If the subject is from a pre-approved list, proceed
5) Optionally check for content as well, depending upon subject
6) Based on the subject determine the relevant "predefined" response
7) Send the response back to the pre-approved sender
8) Mark the mail as read
9) Configure the script in a cron job or windows scheduler to poll every X mins
"""

import imaplib
import smtplib
import email
from IGNORE import raspi_secrets  # Untracked py to carry secrets
from UTILS import mailmap  # Mapping between mail subject and response


IMAP_server = "imap.gmail.com"  # google imap server
SMTP_server = "smtp.gmail.com"  # google smtp server

# List of constants inherited from an untracked file
mail_id = raspi_secrets.login["mail"]
pwd = raspi_secrets.login["password"]

# List of authorized mail ids
authorized_senders = raspi_secrets.authorized_senders

# Dict with subject - response pairs
mail_map = mailmap.mail_map


def imap_login():
    # Instantiate IMAP interface
    imap = imaplib.IMAP4_SSL(IMAP_server)

    # Login to IMAP server
    try:
        status, login_summary = imap.login(mail_id, pwd)
        if status == "OK":
            return status, imap
        else:
            return "login failure", None
    except imaplib.IMAP4.error as e:
        return "login exception: " + str(e), None


def get_unread_mail(imap):
    """ Connect to inbox and fetch unread mails """

    # Select inbox folder
    inbox_status, data = imap.select("Inbox")
    if not inbox_status == "OK":
        return inbox_status, None

    # Search for unread mails
    unread_mail_status, messages = imap.search(None, "(UNSEEN)")
    return unread_mail_status, messages


def is_authorized(mail_id):
    """ Check if the given mail id is from pre-authorized list """
    if email.utils.parseaddr(mail_id)[1] in authorized_senders:
        return True
    else:
        # TODO: Notify owner
        return False


def process_mail(message_data):
    """ Get the sender and subject metadata from each mail """

    for section in message_data:
        if isinstance(section, tuple):
            message = email.message_from_string(section[1])

            sender = message["From"]
            subject = message["Subject"]

            if is_authorized(sender):
                return (sender, subject)  # return as tuple
            else:
                return None


def smtp_login():
    """ Login to smtp server """

    smtpObj = smtplib.SMTP(SMTP_server, 587)  # 587 indicates TLS encryption
    # Send a hello message to establish connection, returns 250 if success
    smtpObj.ehlo()
    smtpObj.starttls()  # start TLS encryption

    # login to server, 235 is returned if success
    smtpObj.login(mail_id, pwd)
    return smtpObj


def send_mail(smtpObj, mail_id, recieved_subject):
    """ Given the mail subject, provide pre-defined response """

    # Send mail
    to_name, to_email = email.utils.parseaddr(mail_id)
    mail_subject = mail_map[recieved_subject]
    mail_body = "Hello {0}, {1}. Cheers".format(to_name, mail_subject)

    smtpObj.sendmail(mail_id,
                     to_email,
                     "subject:" + mail_subject + "\n" + mail_body)


if __name__ == "__main__":
    """ Starting block """

    error_message = ""

    send_mail_queue = list()

    # login to the IMAP server
    login_status, imapObj = imap_login()

    if not login_status == "OK":
        error_message = login_status

    # Fetch unread mail ids
    mail_status, messages = get_unread_mail(imapObj)

    if not mail_status == "OK":
        error_message = mail_status

    # Get data from each unread mail message
    for mail_num in messages[0].split():  # e.g. for 2 mails ['1 2']
        message_code, message_data = imapObj.fetch(mail_num, "(RFC822)")

        if message_code == "OK":
            # returns tuple - mail_id, subject
            entry = process_mail(message_data)
            if entry:
                send_mail_queue.append(entry)

    # Close and logout of IMAP server
    imapObj.close()
    imapObj.logout()

    # Login to SMTP server
    if len(send_mail_queue) > 0:
        smtp = smtp_login()

        # Send mail response from SMTP server
        for item in send_mail_queue:
            mail_id = item[0]
            subject = item[1].lower()

            if subject in mail_map.keys():
                print "Dict match found"
                send_mail(smtp, mail_id, subject)
            else:
                pass
                # TODO: Notify sender abour unrecognized subject

        # Finally disconnect from SMTP server
        smtp.quit()

    # Finally if any error message, print it
    if error_message:
        print error_message

mailbot_py3.py

# mailbot_py3.py
# python 3.5

"""
Mail bot sript that sends predefined response to predefined mails
Intended for raspberry pi, which has its dedicated mail id
Algorithm
1) Check a dedicated mailbox inbox for "unread" mails
2) For each "unread" mail, fetch the sender, subject and content
3) If the sender is from a pre-approved list, proceed
4) If the subject is from a pre-approved list, proceed
5) Optionally check for content as well, depending upon subject
6) Based on the subject determine the relevant "predefined" response
7) Send the response back to the pre-approved sender
8) Mark the mail as read
9) Configure the script in a cron job or windows scheduler to poll every X mins
"""

import imaplib
import smtplib
import email
from IGNORE import raspi_secrets  # Untracked py to carry secrets
from UTILS import mailmap  # Mapping between mail subject and response


IMAP_server = "imap.gmail.com"  # google imap server
SMTP_server = "smtp.gmail.com"  # google smtp server

# List of constants inherited from an untracked file
mail_id = raspi_secrets.login["mail"]
pwd = raspi_secrets.login["password"]

# List of authorized mail ids
authorized_senders = raspi_secrets.authorized_senders

# Dict with subject - response pairs
mail_map = mailmap.mail_map


def imap_login():
    # Instantiate IMAP interface
    imap = imaplib.IMAP4_SSL(IMAP_server)

    # Login to IMAP server
    try:
        status, login_summary = imap.login(mail_id, pwd)
        if status == "OK":
            return status, imap
        else:
            return "login failure", None
    except imaplib.IMAP4.error as e:
        return "login exception: " + str(e), None


def get_unread_mail(imap):
    """ Connect to inbox and fetch unread mails """

    # Select inbox folder
    inbox_status, data = imap.select(mailbox="INBOX")
    if not inbox_status == "OK":
        return inbox_status, None

    # Search for unread mails
    unread_mail_status, messages = imap.search(None, "(UNSEEN)")
    return unread_mail_status, messages


def is_authorized(mail_id):
    """ Check if the given mail id is from pre-authorized list """
    if email.utils.parseaddr(mail_id)[1] in authorized_senders:
        return True
    else:
        # TODO: Notify owner
        return False


def process_mail(message_data):
    """ Get the sender and subject metadata from each mail """

    for section in message_data:
        if isinstance(section, tuple):
            # for python 2.x, change this to message_from_string
            message = email.message_from_bytes(section[1])

            sender = message["From"]
            subject = message["Subject"]

            if is_authorized(sender):
                return (sender, subject)  # return as tuple
            else:
                return None


def smtp_login():
    """ Login to smtp server """

    smtpObj = smtplib.SMTP(SMTP_server, 587)  # 587 indicates TLS encryption
    # Send a hello message to establish connection, returns 250 if success
    smtpObj.ehlo()
    smtpObj.starttls()  # start TLS encryption

    # login to server, 235 is returned if success
    smtpObj.login(mail_id, pwd)
    return smtpObj


def send_mail(smtpObj, mail_id, recieved_subject):
    """ Given the mail subject, provide pre-defined response """

    # Send mail
    to_name, to_email = email.utils.parseaddr(mail_id)
    mail_subject = mail_map[recieved_subject]
    mail_body = "Hello {0}, {1}. Cheers".format(to_name, mail_subject)

    smtpObj.sendmail(mail_id,
                     to_email,
                     "subject:" + mail_subject + "\n" + mail_body)


def main():
    """ Script that controls all function calls """

    send_mail_queue = list()

    # login to the IMAP server
    login_status, imapObj = imap_login()

    if not login_status == "OK":
        return login_status

    # Fetch unread mail ids
    mail_status, messages = get_unread_mail(imapObj)

    if not mail_status == "OK":
        return mail_status

    # Get data from each unread mail message
    for mail_num in messages[0].split():  # e.g. for 2 mails ['1 2']
        message_code, message_data = imapObj.fetch(mail_num, "(RFC822)")

        if message_code == "OK":
            # returns tuple - mail_id, subject
            entry = process_mail(message_data)
            if entry:
                send_mail_queue.append(entry)

    # Close and logout of IMAP server
    imapObj.close()
    imapObj.logout()

    # Login to SMTP server
    if len(send_mail_queue) > 0:
        smtp = smtp_login()

        # Send mail response from SMTP server
        for item in send_mail_queue:
            mail_id = item[0]
            subject = item[1].lower()

            if subject in mail_map.keys():
                send_mail(smtp, mail_id, subject)
            else:
                pass
                # TODO: Notify sender abour unrecognized subject

        # Finally disconnect from SMTP server
        smtp.quit()

    return None


if __name__ == "__main__":
    """ Starting block """

    error_message = main()

    # Finally if any error message, print it
    if error_message:
        print(error_message)