I'm +1 on this solution; it solves the problem in an efficient way without becoming unreadable. I'd shy away from the variants unless/until there's a definite need. kwargs are more explicit, which I think is helpful in readability :)
J On Saturday, November 7, 2015 at 12:16:05 PM UTC+1, Aymeric Augustin wrote: > > Hello, > > Currently the DEFAULT_FILE_STORAGE and STATICFILES_STORAGE settings > contain a dotted Python path to the storage class. The class is > instantiated without any arguments. > > > ** Problem ** > > This leads to three annoyances. > > 1) Third-party libraries like django-storages(-redux) need to provide a > setting for every value that could be required to configure the storage. > This additional level of indirection is annoying. > > If you’re skeptical, look at > https://github.com/jschneier/django-storages/blob/f2880b16b57a36b241a54932255e1a852c0e0ac7/storages/backends/s3boto.py#L204 > . > > 2) Compounding this problem, third-party libraries that want to use a > Django storage backend, but likely not the default one, have no convenient > way for the user to configure the storage. > > Having settings such as `MY_THIRD_PARTY_APP__AWS_ACCESS_KEY_ID` etc. for > every possible storage-related setting sounds unreasonable. > > (This is the problem I’m facing right now with one of my libraries.) > > 3) The standard pattern for working around these problems is > boilerplate-ish: > > my_config = {foo: bar} > > class ConfiguredStorageClass(GenericStorageClass): > def __init__(self, *args, **kwargs): > kwargs.update(my_config) > super().__init__(*args, **kwargs) > > DEFAULT_FILE_STORAGE = 'path.to.ConfiguredStorageClass' > > > ** Proposed solution ** > > To solve this problem, I would like the DEFAULT_FILE_STORAGE and > STATICFILES_STORAGE settings to accept an additional format: a 2-uple of > (dotted Python path to class, init_kwargs). > > This would allow simplifying the example above to: > > DEFAULT_FILE_STORAGE = ‘path.to.GenericStorageClass’, {foo: bar} > > > ** Variants ** > > We could go a bit further support 2-uples with args, 2-uples with kwargs, > and 3-uples with args and kwargs. I didn’t propose it because I’m not sure > this possibility adds much value. Arguments can be passed as kwargs even if > the init method expects them positionally. > > We could support setting DEFAULT_FILE_STORAGE and STATICFILES_STORAGE to > an already initialized instance of a storage class. I’m against this idea > because settings should remain primitive Python values whenever possible. > > We could introduce DEFAULT_FILE_STORAGE_INIT_KWARGS and > STATICFILES_STORAGE_INIT_KWARGS. Well. Perhaps not :-) > > > What do you think? > > -- > Aymeric. > > > > -- You received this message because you are subscribed to the Google Groups "Django developers (Contributions to Django itself)" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-developers+unsubscr...@googlegroups.com. To post to this group, send email to django-developers@googlegroups.com. Visit this group at http://groups.google.com/group/django-developers. To view this discussion on the web visit https://groups.google.com/d/msgid/django-developers/6fc3d5fc-b41d-4e08-9271-2db6c894f83c%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
