feat(client): add rendezvous traversal coordinators (#12)

tests/FinalFactory.Rendezvous.Tests/JoinAttempts/JoinAttemptHttpEndpointTests.cs

@@ -91,14 +91,16 @@ public sealed class JoinAttemptHttpEndpointTests
         using HttpResponseMessage cancelled = await host.HttpClient.SendAsync(cancelRequest);
         Assert.Equal(HttpStatusCode.NoContent, cancelled.StatusCode);
 
-        using HttpRequestMessage emptyPollRequest = new(
+        using HttpRequestMessage cancelledPollRequest = new(
             HttpMethod.Get,
             $"v1/sessions/{session.ListingId}/join-attempts?contractVersion=1&pageSize=10");
-        emptyPollRequest.Headers.Add("X-Rendezvous-Lease-Token", session.LeaseToken);
-        using HttpResponseMessage emptyPollResponse = await host.HttpClient.SendAsync(emptyPollRequest);
-        BrowseHostJoinAttemptsResponse empty = Assert.IsType<BrowseHostJoinAttemptsResponse>(
-            await emptyPollResponse.Content.ReadFromJsonAsync<BrowseHostJoinAttemptsResponse>(ContractJson.Options));
-        Assert.Empty(empty.Items);
+        cancelledPollRequest.Headers.Add("X-Rendezvous-Lease-Token", session.LeaseToken);
+        using HttpResponseMessage cancelledPollResponse = await host.HttpClient.SendAsync(cancelledPollRequest);
+        BrowseHostJoinAttemptsResponse cancelledPoll = Assert.IsType<BrowseHostJoinAttemptsResponse>(
+            await cancelledPollResponse.Content.ReadFromJsonAsync<BrowseHostJoinAttemptsResponse>(ContractJson.Options));
+        HostJoinAttempt cancelledAttempt = Assert.Single(cancelledPoll.Items);
+        Assert.Equal(created.AttemptId, cancelledAttempt.AttemptId);
+        Assert.True(cancelledAttempt.IsCancelled);
     }
 
     private static T AssertSuccess<T>(RendezvousClientResult<T> result)

tests/FinalFactory.Rendezvous.Tests/JoinAttempts/JoinAttemptServiceTests.cs

@@ -152,12 +152,47 @@ public sealed class JoinAttemptServiceTests
         Assert.True(fixture.Service.Cancel(
             created.AttemptId,
             created.ClientPunchCapability).Succeeded);
-        Assert.Empty(fixture.Service.BrowseForHost(
+        Assert.True(fixture.Service.Cancel(
+            created.AttemptId,
+            created.ClientPunchCapability).Succeeded);
+        HostJoinAttempt cancelled = Assert.Single(fixture.Service.BrowseForHost(
             registration.ListingId,
             ContractLimits.ContractVersion,
             registration.LeaseToken,
             10,
             null).Value!.Items);
+        Assert.Equal(created.AttemptId, cancelled.AttemptId);
+        Assert.True(cancelled.IsCancelled);
+    }
+
+    [Fact]
+    public void CancellationAfterIntroductionRevokesTicketIssuanceAndConsumption()
+    {
+        using JoinAttemptFixture fixture = new();
+        (RegisterSessionResponse registration, _) = fixture.CreateHost();
+        CreateJoinAttemptResponse created = fixture.Create(registration.ListingId);
+        IntroductionEndpoints introduction = fixture.Introduce(registration, created);
+        JoinAttemptServiceResult<ConnectionTicketGrant> issued =
+            fixture.Service.IssueConnectionTicket(introduction.Attempt);
+        Assert.True(issued.Succeeded);
+        Assert.True(fixture.Sessions.Capabilities.TryFingerprint(
+            issued.Value!.Ticket,
+            out SecretFingerprint ticketFingerprint));
+
+        Assert.True(fixture.Service.Cancel(
+            created.AttemptId,
+            created.ClientPunchCapability).Succeeded);
+
+        StoredJoinAttempt cancelled = fixture.GetAttempt(registration, created.AttemptId);
+        Assert.True(cancelled.IsCancelled);
+        Assert.Equal(
+            RendezvousErrorCode.Conflict,
+            fixture.Service.IssueConnectionTicket(cancelled).Error);
+        Assert.Equal(
+            StoreResultCode.Conflict,
+            fixture.Sessions.Store.ConsumeConnectionTicket(new(
+                created.AttemptId,
+                ticketFingerprint)).Code);
     }
 
     [Fact]