Webhooks in mailgun backend only work with newest 2.7 pythons

[sebbacon]

hmac.compare_digest is new in 2.7.7. Debian Wheezy, LTS supported until May 2018, is currently at 2.7.3.

As a consequence, trying to use Mailgun mailhooks on Wheezy fails.

I suppose the fix is something like this, along perhaps with a deprecation notice or similar?

[medmunds]

Ah, thanks for the catch. This also affects Mandrill webhooks. Travis-CI is currently running Python 2.7.9 for Python 2.7 builds, so it doesn't catch this.

BTW, even once this is fixed in Anymail, there are some good reasons to run a newer Python 2.7 build, at least for your Django app. (For example, there's likely an urllib3 InsecurePlatformWarning lurking in your logs, where the call to Mailgun's https API can't be verified with the 2.7.3 urllib.) I've used the Deadsnakes PPA to upgrade Python 2.7 on older Ubuntu LTS builds; not sure what the equivalent is for Debian.

[sebbacon]

OK. FWIW I started looking at using tox + pyenv to support a matrix of minor versions in travis, but it all got a bit complicated and I ran out of time :)

Thanks for a great library BTW.