EmailBackend.write_message crashes when self.steam is BufferedWriter

[Bernd Wechner]

I have no idea what's going on here alas, but I had to fix this fast locally. I have three versions of the one Danjgo site running, dev, sandbox and live respectively. I run near identically on each one, and as I fix things on dev test them on sandbox and publish them on live. They are not picture perfect identical although sandbox and live certainly come very close.

Fortunately I can debug all three with PyDev (awesome!) and this is the first time I've had to remotely debug the live site, as it was crashing when users attempt to reset their passwords. it crashed here:

​https://github.com/django/django/blob/4ffada36097ceccfd6f0d358217ac3c40d2a729c/django/core/mail/backends/console.py#L21

and it did so because self.stream at this point, on the live server was of type BufferedWriter while on the sandbox and dev sites it is of type TextIOWrapper.

The latter take strings, and is fed a string at this line. Alas the former does not, it only takes byte strings.

I have no idea how or why these sites deviate in self.stream here, or whence that stemeth. I would like to know, but that would a research project I lack time for in the urgent need to get this site live.

So I patched that method and it now reads:

    def write_message(self, message):
        #import pydevd; pydevd.settrace('192.168.0.11', stdoutToServer=True, stderrToServer=True)
        msg = message.message()
        msg_data = msg.as_bytes()
        charset = msg.get_charset().get_output_charset() if msg.get_charset() else 'utf-8'
        if self.stream.mode.endswith('b'):
            self.stream.write(msg_data)
            self.stream.write(b'\n')
            self.stream.write(b'-' * 79)
            self.stream.write(b'\n')
        else:
            msg_data = msg_data.decode(charset)
            self.stream.write('%s\n' % msg_data)
            self.stream.write('-' * 79)
            self.stream.write('\n')

(you can see my breakpoint in the pydev debugger commented out there)

There are two distinct issues here:

1. How is it possible that self.stream is set to an incompatible type?
2. This method should really be more robust (as pictured) anyhow ...

[Mariusz Felisiak]

Thanks for the report, however it looks like a support question and Trac is not one of support channels. Moreover the console backend is not intended for use in production -- it is provided as a convenience that can be used during development (see ​docs).