Finalize the RP API

[callahad]

Goal

Taking what we've learned from the past two years, define and implement a simplified API that serves the majority of users in the simplest possible manner. This "Goldilocks" API should focus solely on verifying email addresses. It should not be actively involved in session management.

Define

• [ ] Answer unresolved questions, updating task list and spec as appropriate.
  • [ ] Should emailHint live in .request or .watch?
  • [ ] Should returnTo live in .request or .watch?
  • [ ] Should calling .watch multiple times be an error or not?
  • [ ] Should Persona continue to support ToS/PP?
• [ ] Define the basic state of the Goldilocks API.
  • [ ] Core functionality: .watch, .request, onlogin.
  • [ ] Visual Options: siteName, siteLogo, backgroundColor.
  • [ ] Behavior Options: emailHint, returnTo.

Note: Visual options need to live in .watch so they're available to hypothetical browser-native "login" buttons.

Implement

• [ ] Fully implement the RP API in the mozilla/browserid repo.

  Validate

• [ ] Ensure that both prior APIs still work as expected.
• [ ] Port 123done to Goldilocks.
• [ ] Port django-browserid to Goldilocks.

  Finish

• [ ] Update MDN.
• [ ] Blog about new API.
• [ ] Deprecate all prior APIs by notifying persona-notices and dev-identity.