feat: add ephemeral friend presence and invites

Add short-lived capability channels for online friend status and public-room invitations without storing accounts, fingerprints, social graphs, or offline messages.

tests/test_http_api.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import hashlib
 from http.client import HTTPConnection
 import json
 import socketserver
@@ -203,6 +204,95 @@ class DiscoveryHTTPTests(unittest.TestCase):
         self.assertEqual(body["version"], "0.16.2-alpha")
         self.assertEqual(body["build_revision"], "test-build")
 
+    def test_live_friend_presence_and_invitation_endpoints(self) -> None:
+        status, created = self.request("POST", "/v1/rooms", VALID_ROOM)
+        self.assertEqual(status, 201)
+        assert created is not None
+        room = created["room"]
+        traversal = created["traversal"]
+        assert isinstance(room, dict)
+        assert isinstance(traversal, dict)
+        room_id = str(room["room_id"])
+        self.server.registry.verify_endpoint(
+            room_id,
+            str(traversal["verification_token"]),
+            "127.0.0.1",
+            7777,
+        )
+
+        inbox_token = "b" * 64
+        social_version = {
+            "game_version": VALID_ROOM["game_version"],
+            "protocol_version": VALID_ROOM["protocol_version"],
+        }
+        status, polled = self.request(
+            "POST",
+            "/v1/invitations/poll",
+            dict(social_version, inbox_tokens=[inbox_token]),
+        )
+        self.assertEqual(status, 200)
+        assert polled is not None
+        self.assertEqual(polled["invitations"], [])
+
+        status, _sent = self.request(
+            "POST",
+            "/v1/invitations",
+            dict(social_version, inbox_token=inbox_token, room_id=room_id),
+        )
+        self.assertEqual(status, 201)
+        status, polled = self.request(
+            "POST",
+            "/v1/invitations/poll",
+            dict(social_version, inbox_tokens=[inbox_token]),
+        )
+        self.assertEqual(status, 200)
+        assert polled is not None
+        self.assertEqual(polled["invitations"][0]["room"]["room_id"], room_id)
+
+        status, offline = self.request(
+            "POST",
+            "/v1/invitations",
+            dict(social_version, inbox_token="c" * 64, room_id=room_id),
+        )
+        self.assertEqual(status, 409)
+        assert offline is not None
+        self.assertEqual(offline["error"]["code"], "friend_offline")
+        self.assertEqual(
+            offline["error"]["message"],
+            "This person needs to be online to do this.",
+        )
+
+        write_token = "d" * 64
+        channel = hashlib.sha256(
+            f"NETFISHING_PRESENCE_V1:{write_token}".encode()
+        ).hexdigest()
+        status, _published = self.request(
+            "POST",
+            "/v1/presence",
+            dict(
+                social_version,
+                write_tokens=[write_token],
+                online=True,
+                display_name="Voyager",
+                room_id=room_id,
+            ),
+        )
+        self.assertEqual(status, 200)
+        status, presence = self.request(
+            "POST",
+            "/v1/presence/query",
+            dict(social_version, channels=[channel]),
+        )
+        self.assertEqual(status, 200)
+        assert presence is not None
+        self.assertEqual(presence["presence"][0]["room"]["room_id"], room_id)
+
+        self.request(
+            "DELETE",
+            f"/v1/rooms/{room_id}",
+            token=str(created["lease_token"]),
+        )
+
     def test_udp_rendezvous_does_not_spawn_per_packet_threads(self) -> None:
         self.assertFalse(issubclass(TraversalUDPServer, socketserver.ThreadingMixIn))