syndicate-2017/examples/webchat/NOTES.md

Sorting out contact states

Design

Contacts are symmetric: If A follows B, then B follows A.

Let's look at how the state of the A/B relationship changes:

• Initial state: neither A nor B follows the other.

  • ACTION: A adds B to their contacts
    • A proposes an A/B link.
      • ACTION: A may cancel the proposition
        • Return to initial state.
      • ACTION: B may approve the proposition
        • A/B link established.
      • ACTION: B may reject the proposition
        • Return to initial state.
      • ACTION: B may ignore the proposition
        • B's user interface no longer displays the request, but if B subsequently proposes an A/B link, it is as if B approved the previously-proposed link.

• From "A/B link established":

  • ACTION: A may cancel the link
    • Return to initial state.
  • ACTION: B may cancel the link
    • Return to initial state.

B should appear in A's contact list in any of these cases:

1. A has proposed an A/B link.
2. An A/B link exists.

In the first case, B should appear as a "pending link request": as offline, with a "cancel link request" action available.

In the second case, B should appear as fully linked, either offline or online, with a "delete contact" action available.