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pythondjangopython-2.7django-email

Using a colon in a string

I have built a custom invite app for my site. To activate an invite you must follow a link sent to your email.

The issue then becomes, my email sending function is having trouble sending a string as a message that looks like this: 

custom_message = "http://www.something.com%s" % invite.get_absolute_url()

After numerous tests, it seems the issue has to do with the :, since everything seems to work fine without it.

I don't need the colon, as I could just leave the entirety of http:// out. But I am curious why the function won't work when passing this string to my send_custom_email() function

For reference, this is my my email sending function:

def send_custom_email(recipient, custom_message):

    to = recipient
    gmail_user = 'someone@gmail.com'
    gmail_pwd = GMAIL_PWD
    smtpserver = smtplib.SMTP("smtp.gmail.com",587)
    smtpserver.ehlo()
    smtpserver.starttls()
    smtpserver.ehlo
    smtpserver.login(gmail_user, gmail_pwd)
    header = 'To:' + to + '\n' + 'From: ' + gmail_user + '\n' + 'Subject:Invite Link \n'
    print header

    unicoded_custom_message = unicode(custom_message)
    msg = header + unicoded_custom_message

    smtpserver.sendmail(gmail_user, to, msg)
    print 'done!'
    smtpserver.close()

A test:

>>> custom_message ="http://www.somesite.com%s"
>>> send_custom_email(recipient='someotherperson@mailinator.com', custom_message=custom_message)
To:someone@mailinator.com
From: someotherperson@gmail.com
Subject:Invite Link

done!

Although the email is sent, the message doesn't render

Solution

  • The email generated violates the format for emails:

    There has to be a space after the key of a header and there have to be two newlines so separate the message:

    header = 'To: ' + to + '\n' + 'From: ' + gmail_user + '\n' + 'Subject: Invite Link \n\n'

    As you are constructing it, the link is interpreted as email header.

    Also you should consider using Django's built-in email function. Your code is vulnerable tp header injections. Please read: https://docs.djangoproject.com/en/dev/topics/email/ !