UA-.NETStandard/Tests/Opc.Ua.Server.Tests/SessionTests.cs

using System.Threading.Tasks;
using NUnit.Framework;
using Opc.Ua.Server.TestFramework;

namespace Opc.Ua.Server.Tests
{
    [TestFixture]
    [Category("Event")]
    public class SessionTests
    {
        [Test]
        public async Task UpdateDiagnosticCounters_RaisesEvent_WhenPerRequestCounterChangedAsync()
        {
            var fixture = new ServerFixture<StandardServer>(t => new StandardServer(t));
            await fixture.StartAsync().ConfigureAwait(false);

            try
            {
                StandardServer server = fixture.Server;

                (RequestHeader requestHeader, SecureChannelContext secureChannelContext) =
                    await server.CreateAndActivateSessionAsync("UpdateDiagnosticCountersTest").ConfigureAwait(false);

                ISession session = server.CurrentInstance.SessionManager.GetSession(requestHeader.AuthenticationToken);
                Assert.That(session, Is.Not.Null, "Session should exist after Create/Activate.");

                bool eventRaised = false;

                server.CurrentInstance.SessionManager.SessionDiagnosticsChanged += (s, reason)
                    => eventRaised = true;

                uint before = session.SessionDiagnostics.ReadCount.TotalCount;

                // Call ValidateRequest for a request type that maps to a counter (Read).
                session.ValidateRequest(requestHeader, secureChannelContext, RequestType.Read);

                Assert.That(eventRaised, Is.True, "SessionDiagnosticsChanged event should be raised when a per-request counter changes.");
                Assert.That(session.SessionDiagnostics.ReadCount.TotalCount, Is.GreaterThan(before), "ReadCount.TotalCount should have incremented.");
            }
            finally
            {
                await fixture.StopAsync().ConfigureAwait(false);
            }
        }

        [Test]
        [Category("Event")]
        [TestCase(RequestType.Unknown)]
        [TestCase(RequestType.FindServers)]
        [TestCase(RequestType.GetEndpoints)]
        [TestCase(RequestType.CreateSession)]
        [TestCase(RequestType.ActivateSession)]
        [TestCase(RequestType.CloseSession)]
        [TestCase(RequestType.Cancel)]
        public async Task UpdateDiagnosticCounters_DoesNotRaiseEvent_ForIgnoredRequestTypesAsync(RequestType requestType)
        {
            var fixture = new ServerFixture<StandardServer>(t => new StandardServer(t));
            await fixture.StartAsync().ConfigureAwait(false);

            try
            {
                StandardServer server = fixture.Server;

                (RequestHeader requestHeader, SecureChannelContext secureChannelContext) =
                    await server.CreateAndActivateSessionAsync("UpdateDiagnosticCountersIgnoredTest").ConfigureAwait(false);

                ISession session = server.CurrentInstance.SessionManager.GetSession(requestHeader.AuthenticationToken);
                Assert.That(session, Is.Not.Null, "Session should exist after Create/Activate.");

                bool eventRaised = false;

                server.CurrentInstance.SessionManager.SessionDiagnosticsChanged += (s, reason)
                    => eventRaised = true;

                // Capture total requests before; UpdateDiagnosticCounters always increments TotalRequestCount.
                uint totalBefore = session.SessionDiagnostics.TotalRequestCount.TotalCount;

                // Call ValidateRequest with one of the ignored request types.
                session.ValidateRequest(requestHeader, secureChannelContext, requestType);

                Assert.That(
                    session.SessionDiagnostics.TotalRequestCount.TotalCount,
                    Is.EqualTo(totalBefore + 1),
                    "TotalRequestCount should increment for all request types.");

                Assert.That(eventRaised, Is.False, $"SessionDiagnosticsChanged event must NOT be raised for request type {requestType}.");
            }
            finally
            {
                await fixture.StopAsync().ConfigureAwait(false);
            }
        }

        // ------------------------------------------------------------
        // Part 18 §4.4.1 — live identity re-evaluation contract
        // ------------------------------------------------------------

        [Test]
        public async Task IsIdentityStale_FreshSession_StartsFalseAsync()
        {
            var fixture = new ServerFixture<StandardServer>(t => new StandardServer(t));
            await fixture.StartAsync().ConfigureAwait(false);
            try
            {
                StandardServer server = fixture.Server;
                (RequestHeader requestHeader, _) =
                    await server.CreateAndActivateSessionAsync("StaleFresh").ConfigureAwait(false);

                ISession session = server.CurrentInstance.SessionManager
                    .GetSession(requestHeader.AuthenticationToken);

                Assert.That(session.IsIdentityStale, Is.False,
                    "Newly activated sessions must not be marked stale.");
            }
            finally
            {
                await fixture.StopAsync().ConfigureAwait(false);
            }
        }

        [Test]
        public async Task MarkIdentityStale_SetsFlag_AndRefreshClearsItAsync()
        {
            var fixture = new ServerFixture<StandardServer>(t => new StandardServer(t));
            await fixture.StartAsync().ConfigureAwait(false);
            try
            {
                StandardServer server = fixture.Server;
                (RequestHeader requestHeader, _) =
                    await server.CreateAndActivateSessionAsync("StaleFlag").ConfigureAwait(false);

                ISession session = server.CurrentInstance.SessionManager
                    .GetSession(requestHeader.AuthenticationToken);

                IUserIdentity original = session.EffectiveIdentity;
                Assert.That(original, Is.Not.Null);

                session.MarkIdentityStale();
                Assert.That(session.IsIdentityStale, Is.True);

                // Calling MarkIdentityStale again is idempotent.
                session.MarkIdentityStale();
                Assert.That(session.IsIdentityStale, Is.True);

                session.RefreshEffectiveIdentity(original);
                Assert.That(session.IsIdentityStale, Is.False,
                    "RefreshEffectiveIdentity must clear the stale flag.");
                Assert.That(session.EffectiveIdentity, Is.SameAs(original),
                    "Refresh must replace the EffectiveIdentity atomically.");
            }
            finally
            {
                await fixture.StopAsync().ConfigureAwait(false);
            }
        }

        [Test]
        public async Task RefreshEffectiveIdentity_NullIdentity_ThrowsAsync()
        {
            var fixture = new ServerFixture<StandardServer>(t => new StandardServer(t));
            await fixture.StartAsync().ConfigureAwait(false);
            try
            {
                StandardServer server = fixture.Server;
                (RequestHeader requestHeader, _) =
                    await server.CreateAndActivateSessionAsync("StaleArg").ConfigureAwait(false);

                ISession session = server.CurrentInstance.SessionManager
                    .GetSession(requestHeader.AuthenticationToken);

                Assert.Throws<System.ArgumentNullException>(
                    () => session.RefreshEffectiveIdentity(null!),
                    "Passing a null identity must throw to prevent corrupt session state.");
            }
            finally
            {
                await fixture.StopAsync().ConfigureAwait(false);
            }
        }
    }
}