Flyspray

An incorrect email configuration may cause flyspray to hung during several seconds and report an exception.

Environment

* Linux Debian 10
* Nginx
* PHP-7.3 FPM
* Mariadb 10.3
* Flyspray 1.0-rc9

Steps done to create the problem:

1. Cause a misconfiguration in the email configuration (e.g. an email server rejecting the user authentication)
2. Try to post a comment on a ticket to generate a notification

Expected behavior:

Report the error in a logfile and gently show a user-friendly notification

Experienced behavior:

Flyspray hungs during several seconds and reports a user-unfriendly error:
The exception occurs in conditions that generate email notifications (e.g. posting a comment on a ticket):

Notice: fwrite(): send of 6 bytes failed with errno=104 Connection reset by peer in /var/www/flyspray/vendor/swiftmailer/swiftmailer/lib/classes/Swift/Transport/StreamBuffer.php on line 240 Completely unexpected exception: Expected response code 250 but got code "421", with message "XXX edited XXX"
This should never happend, please inform Flyspray Developers