Fix make_cache_key to strip out characters that memcached doesn't like.

Review Request #7318 — Created May 19, 2015 and submitted — Latest diff uploaded

Information

Djblets
release-0.8.x
4144b2a...

Reviewers

memcached keys can't contain spaces, tabs, or newlines. This isn't typically a
problem, but it did surface in trying to use the Review Board post-commit UI
with an SVN branch that contained a space.

This fix updates our make_cache_key implementation to strip out all of those
characters.

Verified that the stripping filtered out things as expected.