How to extract data from Offchain storage?

Question

I'm trying to access data that I'm storing through the RPC off-chain endpoint. I've used OffchainStorage::get() with default config but not getting any data back.

Is there anything do I need to set up explicitly to extract the stored data?

Answer 1

On the client-side we can get the off-chain storage instance from shared backend instance (which is of type Arc < FullBanckend >). This instance can be find inside new_full().

After getting the Bankend's shared instance, we can access our off-chain storage like this:

// The relevant ocw storage instance.
let ocw_storage = backend.offchain_storage();

// Prefix for accessing values for our application.
let prefix = &sp_offchain::STORAGE_PREFIX;

// Get our value
ocw_storage.get(prefix, key);