How to catch errors in async persistence adapter registration

[morgs32]

• I'm using the OPFS adapter.
• And I'm getting this error:

Failed to execute 'getFileHandle' on 'FileSystemDirectoryHandle': Name is not allowed

• I wonder if it's because I'm on localhost. I will try to repro on stackblitz

But regardless, I'd love to catch errors with adapters and then use a different adapter. Such as if we can't use OPFS I fallback to localstorage.

A catch here is that I like that new Collection is synchronous. Maybe in isReady() we could catch and substitute a different adapter? Hmm I feel like I need to think about this more...

Still worth creating this issue to discuss further? Happy to move to a discussion...

[maxnowack]

The persistence.error event is triggered when an error occurs during registration. In your case, implementing a fallback to a different persistence adapter is probably only feasible with a custom adapter. However, this custom adapter could simply wrap existing persistence adapters and act as a proxy. I’m using a similar approach in my project.

Here’s an example how a fallback adapter could look like.

function createFallbackPersistenceAdapter(name: string) {
  let usedAdapter: PersistenceAdapter = createOPFSAdapter(name)
  const initializeFallbackAdapter = () => createLocalStorageAdapter(name)

  return createPersistenceAdapter({
    register: async (...args) => {
      try {
        return await usedAdapter.register(...args)
      } catch (error) {
        usedAdapter = initializeFallbackAdapter()
        return usedAdapter.register(...args)
      }
    },
    load: async (...args) => usedAdapter.load(...args),
    save: async (...args) => usedAdapter.save(...args),
  })
}