Use strings for cache keys #226
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| @@ -22,7 +22,7 @@ def keyfmt(k, v=None): | |||
| key = prefix + k | |||
| else: | |||
| key = prefix + hashlib.md5((k % v).encode('utf-8')).hexdigest() | |||
| return key.encode('utf-8') | |||
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Hmm, this was added specifically because unencoded utf8 characters break multiple cache backends (in particular memcache). The Python code is OK with it, but memcached itself was not. If the CACHE_PREFIX setting is set to an unsafe string, this will break. k should only come from within the library, so that should be OK, and v gets encoded and digested, so it should be safe.
At the very least, this would need docs added to the settings reference that made it clear CACHE_PREFIX needs to be plain ascii.
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The plain ASCII restrict exists on memcache but afaik all other Django core cache backends support unicode, or can support it in the right conditions, e.g. correct database setup for dbcache. I can document it, but Django does already emit warnings when forming cache keys that won't work on memcached: https://github.com/django/django/blob/master/django/core/cache/backends/base.py#L226
As discovered in adamchainz/django-perf-rec#21, django-waffle is using `bytes` objects for cache keys. This seems to work with most of the caching infrastructure, but it's not documented as supported in the [Django cache docs](https://docs.djangoproject.com/en/1.10/topics/cache/) nor does it seem to be tested for in its test suite. Thus some cache backends may not support `bytes`, and `django-perf-rec` currently doesn't support them either.
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This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. |
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This issue has been closed as stale because it has not had any recent activity. Please feel free to re-open if the issue is still relevant. Thank you for your contributions! |
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Hi there! Just wanted to note that I'm having the same issue using |
As discovered in adamchainz/django-perf-rec#21, django-waffle is using
bytesobjects for cache keys. This seems to work with most of the caching infrastructure, but it's not documented as supported in the Django cache docs nor does it seem to be tested for in its test suite. Thus some cache backends may not supportbytes, anddjango-perf-reccurrently doesn't support them either.