Flask – Mail


Advertisements

A web based application is often required to have a feature of sending mail to the users/clients. Flask-Mail extension makes it very easy to set up a simple interface with any email server.

At first, Flask-Mail extension should be installed with the help of pip utility.

pip install Flask-Mail

Then Flask-Mail needs to be configured by setting values of the following application parameters.

Sr.No Parameters & Description
1

MAIL_SERVER

Name/IP address of email server

2

MAIL_PORT

Port number of server used

3

MAIL_USE_TLS

Enable/disable Transport Security Layer encryption

4

MAIL_USE_SSL

Enable/disable Secure Sockets Layer encryption

5

MAIL_DEBUG

Debug support. Default is Flask application’s debug status

6

MAIL_USERNAME

User name of sender

7

MAIL_PASSWORD

password of sender

8

MAIL_DEFAULT_SENDER

sets default sender

9

MAIL_MAX_EMAILS

Sets maximum mails to be sent

10

MAIL_SUPPRESS_SEND

Sending suppressed if app.testing set to true

11

MAIL_ASCII_ATTACHMENTS

If set to true, attached filenames converted to ASCII

The flask-mail module contains definitions of the following important classes.

Mail class

It manages email-messaging requirements. The class constructor takes the following form −

flask-mail.Mail(app = None)

The Constructor takes the Flask application object as a parameter.

Methods of Mail class

Sr.No Methods & Description
1

send()

Sends contents of Message class object

2

connect()

Opens connection with mail host

3

send_message()

Sends message object

Message class

It encapsulates an email message. Message class constructor has several parameters −

flask-mail.Message(subject, recipients, body, html, sender, cc, bcc, 
   reply-to, date, charset, extra_headers, mail_options, rcpt_options)

Message class methods

attach() − adds an attachment to message. This method takes the following parameters −

  • filename − name of file to attach

  • content_type − MIME type of file

  • data − raw file data

  • disposition − content disposition, if any.

add_recipient() − adds another recipient to message

In the following example, SMTP server of Google’s gmail service is used as MAIL_SERVER for Flask-Mail configuration.

Step 1 − Import Mail and Message class from flask-mail module in the code.

from flask_mail import Mail, Message

Step 2 − Then Flask-Mail is configured as per following settings.

app.config['MAIL_SERVER']='smtp.gmail.com'
app.config['MAIL_PORT'] = 465
app.config['MAIL_USERNAME'] = 'yourId@gmail.com'
app.config['MAIL_PASSWORD'] = '*****'
app.config['MAIL_USE_TLS'] = False
app.config['MAIL_USE_SSL'] = True

Step 3 − Create an instance of Mail class.

mail = Mail(app)

Step 4 − Set up a Message object in a Python function mapped by URL rule (‘/’).

@app.route("/")
def index():
   msg = Message('Hello', sender = 'yourId@gmail.com', recipients = ['id1@gmail.com'])
   msg.body = "This is the email body"
   mail.send(msg)
   return "Sent"

Step 5 − The entire code is given below. Run the following script in Python Shell and visit http://localhost:5000/.

from flask import Flask
from flask_mail import Mail, Message

app =Flask(__name__)
mail=Mail(app)

app.config['MAIL_SERVER']='smtp.gmail.com'
app.config['MAIL_PORT'] = 465
app.config['MAIL_USERNAME'] = 'yourId@gmail.com'
app.config['MAIL_PASSWORD'] = '*****'
app.config['MAIL_USE_TLS'] = False
app.config['MAIL_USE_SSL'] = True
mail = Mail(app)

@app.route("/")
def index():
   msg = Message('Hello', sender = 'yourId@gmail.com', recipients = ['id1@gmail.com'])
   msg.body = "Hello Flask message sent from Flask-Mail"
   mail.send(msg)
   return "Sent"

if __name__ == '__main__':
   app.run(debug = True)

Note that the built-insecurity features in Gmail service may block this login attempt. You may have to decrease the security level. Please log in to your Gmail account and visit this link to decrease the security.

Decrease the Security
Advertisements