Hello,
The core of the proposed solution seems quite interesting; however, it also introduces a new configuration format for backends. Caches and databases use a dict with a "BACKEND" key and an "OPTIONS" dict for kwargs to pass to the backend. Likewise, entries in the TEMPLATES list are dicts with a "BACKEND" key and various options. Do you think that the new setting should match these options instead of the proposed two-tuples? -- Raphaël On Sat, 7 Nov 2015 12:15:49 +0100 Aymeric Augustin <aymeric.augus...@polytechnique.org> 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 > <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? > -- 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/20151107125832.440abc17%40corvis. For more options, visit https://groups.google.com/d/optout.
