Provider: Implement crypto-wallet-based authentication

[BracketJohn]

Describe the feature

Goal

Implement a wallet-based login.

Context

On one of our engagements we needed to implement authentication using chain-wallets. We would love to transfer it to this project to offer the same functionality to Nuxt 3 users for an easy entry into the crypto-space.

Providers in nuxt-auth generally have two components:

• client-side functionality
  • authjs provider: https://github.com/sidebase/nuxt-auth/tree/main/src/runtime/composables/authjs
  • local provider: https://github.com/sidebase/nuxt-auth/tree/main/src/runtime/composables/local
• server-side functionality
  • authjs provider: https://github.com/sidebase/nuxt-auth/tree/main/src/runtime/server/services/authjs
  • local provider: Not applicable, this could be any backend that provides username & password based flows. A reference implementation using nuxt 3 can be found here: https://github.com/sidebase/nuxt-auth/tree/main/playground-local/server/api/auth

For our implementation here client-only + a reference server-side implementation should be sufficient. Later on we can think about providing server-side utilities, but that will also force us to think about default ways to specify DB-adapters and more.

Based on this scope-limitation using the local provider as an implementation example should be most helpful. Another interesting resource: @danielwinkelmann started on an implementation of a refresh provider in #373. The refresh provider is very similar to the local provider with the addition of a periodic token-refresh.

Other notes:

• Add all documentation into the docs/v0.6/ folder -> this feature will only be supported by the new v0.6
• All dependencies that are provider-specific:
  • should be added as peer dependencies
  • should be documented as provider specfic setup on the installation page (e.g., see https://sidebase.io/nuxt-auth/v0.6/getting-started/installation for local and authjs already documented)
• don't forget to document new configuration you add

Assets

Related issue + implementation of ethereum based authentication: https://github.com/powerhouse-inc/switchboard-boilerplate/issues/52

Tasks

• [ ] Ask any questions that arise
• [ ] Implement the provider
• [ ] Implement a playground for the provider + instructions on how to use

Additional information

No response

[valiafetisov]

Looking at the linked composables I don't think most of those (sign in, sign out, token management, etc) needs to be reimplemented in order to support "Sign-In with Ethereum" functionality. I would instead contribute a smaller abstraction (e.g. adapter/integration/provider, not sure what's the vocabulary here) – a relatively small part of code:

• a function/endpoint to generate a challenge (message that needs to be signed)
• a function/endpoint to validate the challenge (checks signature and other security-related parts)
• maybe extra frontend helper to trigger the browser extension and call endpoints (i.e. web-based wallet)

And I imagine that if it's just a provider, it can even live in a different repo/example implementation.

Do you see a technical/organisational problem with what I've described?

[BracketJohn]

Do you see a technical/organisational problem with what I've described?

Not at all! Proposal: Add a new playground-ethereum/ folder by cope-pasting the local playground. Then you have the freedom to in parallel:

• work on a reference / example implementation inside the playground-ethereum/ folder
• apply any required module changes directly to the module code

In the end we'll have a full picture of what complexity stays on the users' app-side and what complexity will be moved into the module.

In the future or right in that PR we can then also discuss & move the balance of this abstraction further into the module or into the users' app.