Asynchronous mail sending

[scalloty]

Hi,

I want to send email asynchronously. I tried with Thread in decorator, but maybe quite normal leads to error:

RuntimeError: working outside of application context

Is there an elegant solution to this problem?

[neurosnap]

I'm not entirely sure this is possible using Flask, because it doesn't support asyncio or threading at all.

[scalloty]

That is, you say that this is impossible?

http://blog.miguelgrinberg.com/post/the-flask-mega-tutorial-part-xi-email-support

I'm sure this is possible.

[neurosnap]

Ah this tutorial is not waiting for a response. Make sure you are working within the app context.

from threading import Thread
from app import app

def send_async_email(app, msg):
    with app.app_context():
        mail.send(msg)

def send_email(subject, sender, recipients, text_body, html_body):
    msg = Message(subject, sender=sender, recipients=recipients)
    msg.body = text_body
    msg.html = html_body
    thr = Thread(target=send_async_email, args=[app, msg])
    thr.start()

with app.app_context() being the part that sets the application context. Do you have some code to share?

[scalloty]

I want to call def send_email() in email.py asyncio in new thread.
I created new decorator:

def async(f):
def wrapper(_args, *_kwargs):
thr = Thread(target=f, args=args, kwargs=kwargs)
thr.start()
return wrapper

and set @async on send_email()
also added: with current_app.app_context(): before mail_engine.send(message) in send_email()
still have error:
RuntimeError: working outside of application context

[szastupov]

I know this issue is old but I figured I should comment on it. A better solution to this problem would be to configure a local SMTP server (postfix for example) to relay messages to your mail provider. This way you remove the blocking delay and Postfix will work as a simple but reliable queue.

If you're on Amazon and not into configuring Postfix, just use Amazon SES.

[sajadreshi]

I followed the same article give above and ran into same issue. Just wondering if you happened to find a solution to the problem.