Make repr of NoValue output a consistent value
Paul Brown
Branch: pawl/dogpile.cache:add_no_value_repr
Branch: zzzeek/dogpile.cache:master
Declined
Declined pull request
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Closed by: Mike Bayer·2017-06-23
I was creating a cache key based off of another cache key like this:
last_updated = cache_region.get('last_updated') cache_key = 'posts_{}'.format(last_updated) cache_region.get(cache_key)In that case,
cache_keyends up being something like: `posts_<dogpile.cache.api.NoValue object at 0x10360cc10>That caused an unexpected bug where each web worker had a different memory location for NoValue and the web application was getting/setting to different cache keys for effectively the same thing.
I ended up fixing it like this:
from dogpile.cache.api import NO_VALUE last_updated = cache_region.get('last_updated') if last_updated is NO_VALUE: last_updated = NoneHowever, I think we could prevent some potential bugs if we set the
__repr__of NoValue to something consistent like this PR does.