Allow brownfield apps to handle requests

[tido64]

Motivation

We have brownfield apps with existing storage solutions that we want our React Native components to take advantage of. For example, one of our apps use PINCache to control lifetime of the stored data and the size of the disk cache.

Description

Before I start implementing on this, I'd like to run you by my solution and get some feedback on whether I'm on the correct path.

In RNCAsyncStorage, we add a delegate @property, e.g.:

@property (nonatomic, weak, nullable) id<RNCAsyncStorageDelegate> delegate;

For every RCT_EXPORT_METHOD, we call the delegate if it's set, otherwise we do the normal operations.

Consumers can then set the delegate like so:

RNCAsyncStorage *asyncStorage = [bridge moduleForClass:[RNCAsyncStorage class]];
asyncStorage.delegate = self;

Let me know what you think.

Thanks.

[krizzu]

Hey @tido64
So, if I understood correctly, you want to expand AS capabilities, by attaching delegates to external storage solutions?

I like the idea. I was thinking about a way to make Async Storage extendable - by applying adapters for external storages.

Are you planning on including this feature in Android too?

[tido64]

Yes, that's correct. I haven't looked at the Android implementation yet but we do need it, so I will look at it next when I have time.

[tido64]

Merged. Thanks, @krizzu 🎉