Function open_encrypted_storage 

pub async fn open_encrypted_storage(
    storage: Arc<dyn PeerStorage>,
    db: &str,
    keyring: Option<&Arc<dyn Keyring>>,
) -> Result<Arc<dyn PeerStorage>, StoreError>

Resolves the storage keys db needs and wraps storage when it is encrypted.

Returns storage unchanged for an unencrypted database, so a peer that holds no keyring keeps working exactly as before against one.

Errors

Returns StoreError when the manifest cannot be read, when the database is encrypted and keyring is absent, or when an epoch cannot be unwrapped.