Add Galaxy repository API and clients

2026-04-29 07:27:00 -04:00
parent 047d875fe6
commit 133c83029b
103 changed files with 22788 additions and 39 deletions
@@ -1,4 +1,5 @@
 using MxGateway.Contracts.Proto;
+using MxGateway.Contracts.Proto.Galaxy;

 namespace MxGateway.Client.Cli;

@@ -19,4 +20,20 @@ public interface IMxGatewayCliClient : IAsyncDisposable
    IAsyncEnumerable<MxEvent> StreamEventsAsync(
        StreamEventsRequest request,
        CancellationToken cancellationToken);
+
+    Task<TestConnectionReply> GalaxyTestConnectionAsync(
+        TestConnectionRequest request,
+        CancellationToken cancellationToken);
+
+    Task<GetLastDeployTimeReply> GalaxyGetLastDeployTimeAsync(
+        GetLastDeployTimeRequest request,
+        CancellationToken cancellationToken);
+
+    Task<DiscoverHierarchyReply> GalaxyDiscoverHierarchyAsync(
+        DiscoverHierarchyRequest request,
+        CancellationToken cancellationToken);
+
+    IAsyncEnumerable<DeployEvent> GalaxyWatchDeployEventsAsync(
+        WatchDeployEventsRequest request,
+        CancellationToken cancellationToken);
 }
@@ -1,40 +1,84 @@
 using MxGateway.Client;
 using MxGateway.Contracts.Proto;
+using MxGateway.Contracts.Proto.Galaxy;

 namespace MxGateway.Client.Cli;

-internal sealed class MxGatewayCliClientAdapter(MxGatewayClient client) : IMxGatewayCliClient
+internal sealed class MxGatewayCliClientAdapter : IMxGatewayCliClient
 {
+    private readonly MxGatewayClient _client;
+    private readonly Lazy<GalaxyRepositoryClient> _galaxyClient;
+
+    public MxGatewayCliClientAdapter(MxGatewayClient client)
+    {
+        _client = client;
+        _galaxyClient = new Lazy<GalaxyRepositoryClient>(
+            () => GalaxyRepositoryClient.Create(_client.Options));
+    }
+
    public Task<OpenSessionReply> OpenSessionAsync(
        OpenSessionRequest request,
        CancellationToken cancellationToken)
    {
-        return client.OpenSessionRawAsync(request, cancellationToken);
+        return _client.OpenSessionRawAsync(request, cancellationToken);
    }

    public Task<CloseSessionReply> CloseSessionAsync(
        CloseSessionRequest request,
        CancellationToken cancellationToken)
    {
-        return client.CloseSessionRawAsync(request, cancellationToken);
+        return _client.CloseSessionRawAsync(request, cancellationToken);
    }

    public Task<MxCommandReply> InvokeAsync(
        MxCommandRequest request,
        CancellationToken cancellationToken)
    {
-        return client.InvokeAsync(request, cancellationToken);
+        return _client.InvokeAsync(request, cancellationToken);
    }

    public IAsyncEnumerable<MxEvent> StreamEventsAsync(
        StreamEventsRequest request,
        CancellationToken cancellationToken)
    {
-        return client.StreamEventsAsync(request, cancellationToken);
+        return _client.StreamEventsAsync(request, cancellationToken);
    }

-    public ValueTask DisposeAsync()
+    public Task<TestConnectionReply> GalaxyTestConnectionAsync(
+        TestConnectionRequest request,
+        CancellationToken cancellationToken)
    {
-        return client.DisposeAsync();
+        return _galaxyClient.Value.TestConnectionRawAsync(request, cancellationToken);
+    }
+
+    public Task<GetLastDeployTimeReply> GalaxyGetLastDeployTimeAsync(
+        GetLastDeployTimeRequest request,
+        CancellationToken cancellationToken)
+    {
+        return _galaxyClient.Value.GetLastDeployTimeRawAsync(request, cancellationToken);
+    }
+
+    public Task<DiscoverHierarchyReply> GalaxyDiscoverHierarchyAsync(
+        DiscoverHierarchyRequest request,
+        CancellationToken cancellationToken)
+    {
+        return _galaxyClient.Value.DiscoverHierarchyRawAsync(request, cancellationToken);
+    }
+
+    public IAsyncEnumerable<DeployEvent> GalaxyWatchDeployEventsAsync(
+        WatchDeployEventsRequest request,
+        CancellationToken cancellationToken)
+    {
+        return _galaxyClient.Value.WatchDeployEventsRawAsync(request, cancellationToken);
+    }
+
+    public async ValueTask DisposeAsync()
+    {
+        if (_galaxyClient.IsValueCreated)
+        {
+            await _galaxyClient.Value.DisposeAsync().ConfigureAwait(false);
+        }
+
+        await _client.DisposeAsync().ConfigureAwait(false);
    }
 }
@@ -3,6 +3,7 @@ using System.Text.Json;
 using Google.Protobuf;
 using MxGateway.Client;
 using MxGateway.Contracts.Proto;
+using MxGateway.Contracts.Proto.Galaxy;

 namespace MxGateway.Client.Cli;

@@ -70,7 +71,7 @@ public static class MxGatewayClientCli
            }

            await using IMxGatewayCliClient client = clientFactory(CreateOptions(arguments));
-            using CancellationTokenSource cancellation = CreateCancellation(arguments);
+            using CancellationTokenSource cancellation = CreateCancellation(arguments, command);

            return command switch
            {
@@ -98,6 +99,14 @@ public static class MxGatewayClientCli
                    .ConfigureAwait(false),
                "smoke" => await SmokeAsync(arguments, client, standardOutput, cancellation.Token)
                    .ConfigureAwait(false),
+                "galaxy-test-connection" => await GalaxyTestConnectionAsync(arguments, client, standardOutput, cancellation.Token)
+                    .ConfigureAwait(false),
+                "galaxy-last-deploy" => await GalaxyLastDeployAsync(arguments, client, standardOutput, cancellation.Token)
+                    .ConfigureAwait(false),
+                "galaxy-discover" => await GalaxyDiscoverAsync(arguments, client, standardOutput, cancellation.Token)
+                    .ConfigureAwait(false),
+                "galaxy-watch" => await GalaxyWatchAsync(arguments, client, standardOutput, cancellation.Token)
+                    .ConfigureAwait(false),
                _ => WriteUnknownCommand(command, standardError),
            };
        }
@@ -168,9 +177,18 @@ public static class MxGatewayClientCli
            $"Gateway API key is required. Pass --api-key or set {apiKeyEnvironmentName}.");
    }

-    private static CancellationTokenSource CreateCancellation(CliArguments arguments)
+    private static CancellationTokenSource CreateCancellation(CliArguments arguments, string command)
    {
        var cancellation = new CancellationTokenSource();
+        // Long-running streaming commands run until Ctrl+C / cancellation by default;
+        // a caller-supplied --timeout still applies if present.
+        bool isLongRunning = command is "galaxy-watch";
+        string? rawTimeout = arguments.GetOptional("timeout");
+        if (isLongRunning && string.IsNullOrWhiteSpace(rawTimeout))
+        {
+            return cancellation;
+        }
+
        TimeSpan timeout = arguments.GetDuration("timeout", TimeSpan.FromSeconds(30));
        cancellation.CancelAfter(timeout);
        return cancellation;
@@ -766,6 +784,146 @@ public static class MxGatewayClientCli
            .ToMxValue();
    }

+    private static Task<int> GalaxyTestConnectionAsync(
+        CliArguments arguments,
+        IMxGatewayCliClient client,
+        TextWriter output,
+        CancellationToken cancellationToken)
+    {
+        return WriteReplyAsync(
+            client.GalaxyTestConnectionAsync(new TestConnectionRequest(), cancellationToken),
+            arguments,
+            output);
+    }
+
+    private static Task<int> GalaxyLastDeployAsync(
+        CliArguments arguments,
+        IMxGatewayCliClient client,
+        TextWriter output,
+        CancellationToken cancellationToken)
+    {
+        return WriteReplyAsync(
+            client.GalaxyGetLastDeployTimeAsync(new GetLastDeployTimeRequest(), cancellationToken),
+            arguments,
+            output);
+    }
+
+    private static async Task<int> GalaxyDiscoverAsync(
+        CliArguments arguments,
+        IMxGatewayCliClient client,
+        TextWriter output,
+        CancellationToken cancellationToken)
+    {
+        DiscoverHierarchyReply reply = await client.GalaxyDiscoverHierarchyAsync(
+                new DiscoverHierarchyRequest(),
+                cancellationToken)
+            .ConfigureAwait(false);
+
+        if (arguments.HasFlag("json"))
+        {
+            output.WriteLine(ProtobufJsonFormatter.Format(reply));
+            return 0;
+        }
+
+        output.WriteLine($"objects={reply.Objects.Count}");
+        foreach (GalaxyObject galaxyObject in reply.Objects)
+        {
+            output.WriteLine($"- gobject_id={galaxyObject.GobjectId} tag_name={galaxyObject.TagName} contained_name={galaxyObject.ContainedName} parent={galaxyObject.ParentGobjectId} attributes={galaxyObject.Attributes.Count}");
+        }
+
+        return 0;
+    }
+
+    private static async Task<int> GalaxyWatchAsync(
+        CliArguments arguments,
+        IMxGatewayCliClient client,
+        TextWriter output,
+        CancellationToken cancellationToken)
+    {
+        bool json = arguments.HasFlag("json");
+        uint maxEvents = arguments.GetUInt32("max-events", 0);
+        if (maxEvents > MaxAggregateEvents)
+        {
+            throw new ArgumentException($"--max-events cannot exceed {MaxAggregateEvents}.");
+        }
+
+        WatchDeployEventsRequest request = new();
+        string? lastSeen = arguments.GetOptional("last-seen-deploy-time");
+        if (!string.IsNullOrWhiteSpace(lastSeen))
+        {
+            DateTimeOffset parsed = DateTimeOffset.Parse(
+                lastSeen,
+                CultureInfo.InvariantCulture,
+                DateTimeStyles.AssumeUniversal | DateTimeStyles.AdjustToUniversal);
+            request.LastSeenDeployTime = Google.Protobuf.WellKnownTypes.Timestamp.FromDateTimeOffset(parsed);
+        }
+
+        using CancellationTokenSource linked = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
+        ConsoleCancelEventHandler handler = (_, eventArgs) =>
+        {
+            eventArgs.Cancel = true;
+            try
+            {
+                linked.Cancel();
+            }
+            catch (ObjectDisposedException)
+            {
+            }
+        };
+        Console.CancelKeyPress += handler;
+
+        uint emitted = 0;
+        try
+        {
+            await foreach (DeployEvent deployEvent in client
+                .GalaxyWatchDeployEventsAsync(request, linked.Token)
+                .WithCancellation(linked.Token)
+                .ConfigureAwait(false))
+            {
+                if (json)
+                {
+                    output.WriteLine(ProtobufJsonFormatter.Format(deployEvent));
+                }
+                else
+                {
+                    output.WriteLine(FormatDeployEvent(deployEvent));
+                }
+
+                emitted++;
+                if (maxEvents > 0 && emitted >= maxEvents)
+                {
+                    break;
+                }
+            }
+        }
+        catch (OperationCanceledException) when (linked.IsCancellationRequested && !cancellationToken.IsCancellationRequested)
+        {
+            // Ctrl+C-driven cancellation is a clean exit.
+        }
+        finally
+        {
+            Console.CancelKeyPress -= handler;
+        }
+
+        return 0;
+    }
+
+    private static string FormatDeployEvent(DeployEvent deployEvent)
+    {
+        string deployTime = deployEvent.TimeOfLastDeployPresent && deployEvent.TimeOfLastDeploy is not null
+            ? deployEvent.TimeOfLastDeploy
+                .ToDateTimeOffset()
+                .ToString("O", CultureInfo.InvariantCulture)
+            : "<none>";
+        string observed = deployEvent.ObservedAt is not null
+            ? deployEvent.ObservedAt
+                .ToDateTimeOffset()
+                .ToString("O", CultureInfo.InvariantCulture)
+            : "<unknown>";
+
+        return $"sequence={deployEvent.Sequence} observed_at={observed} time_of_last_deploy={deployTime} objects={deployEvent.ObjectCount} attributes={deployEvent.AttributeCount}";
+    }
+
    private static int WriteUnknownCommand(string command, TextWriter standardError)
    {
        standardError.WriteLine($"Unknown command '{command}'.");
@@ -793,7 +951,11 @@ public static class MxGatewayClientCli
            or "stream-events"
            or "write"
            or "write2"
-            or "smoke";
+            or "smoke"
+            or "galaxy-test-connection"
+            or "galaxy-last-deploy"
+            or "galaxy-discover"
+            or "galaxy-watch";
    }

    private static IReadOnlyList<string> ParseStringList(string value)
@@ -842,5 +1004,9 @@ public static class MxGatewayClientCli
        writer.WriteLine("mxgw-dotnet write --session-id <id> --server-handle <n> --item-handle <n> --type <type> --value <value> [--json]");
        writer.WriteLine("mxgw-dotnet write2 --session-id <id> --server-handle <n> --item-handle <n> --type <type> --value <value> [--timestamp <iso>] [--json]");
        writer.WriteLine("mxgw-dotnet smoke --item <ref> [--value <value> --type <type>] [--json]");
+        writer.WriteLine("mxgw-dotnet galaxy-test-connection [--json]");
+        writer.WriteLine("mxgw-dotnet galaxy-last-deploy [--json]");
+        writer.WriteLine("mxgw-dotnet galaxy-discover [--json]");
+        writer.WriteLine("mxgw-dotnet galaxy-watch [--last-seen-deploy-time <iso8601>] [--max-events <n>] [--json]");
    }
 }
@@ -0,0 +1,103 @@
+using Grpc.Core;
+using MxGateway.Contracts.Proto.Galaxy;
+
+namespace MxGateway.Client.Tests;
+
+internal sealed class FakeGalaxyRepositoryTransport(MxGatewayClientOptions options) : IGalaxyRepositoryClientTransport
+{
+    public MxGatewayClientOptions Options { get; } = options;
+
+    public GalaxyRepository.GalaxyRepositoryClient? RawClient => null;
+
+    public List<(TestConnectionRequest Request, CallOptions CallOptions)> TestConnectionCalls { get; } = [];
+
+    public List<(GetLastDeployTimeRequest Request, CallOptions CallOptions)> GetLastDeployTimeCalls { get; } = [];
+
+    public List<(DiscoverHierarchyRequest Request, CallOptions CallOptions)> DiscoverHierarchyCalls { get; } = [];
+
+    public TestConnectionReply TestConnectionReply { get; set; } = new() { Ok = true };
+
+    public GetLastDeployTimeReply GetLastDeployTimeReply { get; set; } = new() { Present = false };
+
+    public DiscoverHierarchyReply DiscoverHierarchyReply { get; set; } = new();
+
+    public Queue<Exception> TestConnectionExceptions { get; } = new();
+
+    public Queue<Exception> GetLastDeployTimeExceptions { get; } = new();
+
+    public Queue<Exception> DiscoverHierarchyExceptions { get; } = new();
+
+    public Task<TestConnectionReply> TestConnectionAsync(
+        TestConnectionRequest request,
+        CallOptions callOptions)
+    {
+        TestConnectionCalls.Add((request, callOptions));
+        if (TestConnectionExceptions.TryDequeue(out Exception? exception))
+        {
+            throw exception;
+        }
+
+        return Task.FromResult(TestConnectionReply);
+    }
+
+    public Task<GetLastDeployTimeReply> GetLastDeployTimeAsync(
+        GetLastDeployTimeRequest request,
+        CallOptions callOptions)
+    {
+        GetLastDeployTimeCalls.Add((request, callOptions));
+        if (GetLastDeployTimeExceptions.TryDequeue(out Exception? exception))
+        {
+            throw exception;
+        }
+
+        return Task.FromResult(GetLastDeployTimeReply);
+    }
+
+    public Task<DiscoverHierarchyReply> DiscoverHierarchyAsync(
+        DiscoverHierarchyRequest request,
+        CallOptions callOptions)
+    {
+        DiscoverHierarchyCalls.Add((request, callOptions));
+        if (DiscoverHierarchyExceptions.TryDequeue(out Exception? exception))
+        {
+            throw exception;
+        }
+
+        return Task.FromResult(DiscoverHierarchyReply);
+    }
+
+    public List<(WatchDeployEventsRequest Request, CallOptions CallOptions)> WatchDeployEventsCalls { get; } = [];
+
+    public List<DeployEvent> WatchDeployEvents { get; } = [];
+
+    public Exception? WatchDeployEventsException { get; set; }
+
+    /// <summary>
+    /// When set, awaited before each event yield so tests can observe cancellation
+    /// mid-stream. Receives the call's cancellation token.
+    /// </summary>
+    public Func<CancellationToken, Task>? WatchDeployEventsBeforeYield { get; set; }
+
+    public async IAsyncEnumerable<DeployEvent> WatchDeployEventsAsync(
+        WatchDeployEventsRequest request,
+        CallOptions callOptions)
+    {
+        WatchDeployEventsCalls.Add((request, callOptions));
+
+        if (WatchDeployEventsException is not null)
+        {
+            throw WatchDeployEventsException;
+        }
+
+        foreach (DeployEvent deployEvent in WatchDeployEvents)
+        {
+            if (WatchDeployEventsBeforeYield is not null)
+            {
+                await WatchDeployEventsBeforeYield(callOptions.CancellationToken).ConfigureAwait(false);
+            }
+
+            callOptions.CancellationToken.ThrowIfCancellationRequested();
+            yield return deployEvent;
+        }
+    }
+}
@@ -0,0 +1,301 @@
+using Google.Protobuf.WellKnownTypes;
+using Grpc.Core;
+using MxGateway.Contracts.Proto.Galaxy;
+
+namespace MxGateway.Client.Tests;
+
+public sealed class GalaxyRepositoryClientTests
+{
+    [Fact]
+    public async Task TestConnectionAsync_AttachesApiKeyMetadataAndReturnsOkFlag()
+    {
+        using CancellationTokenSource cancellation = new();
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.TestConnectionReply = new TestConnectionReply { Ok = true };
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        bool ok = await client.TestConnectionAsync(cancellation.Token);
+
+        Assert.True(ok);
+        var call = Assert.Single(transport.TestConnectionCalls);
+        Assert.Equal("Bearer test-api-key", call.CallOptions.Headers?.GetValue("authorization"));
+    }
+
+    [Fact]
+    public async Task TestConnectionAsync_ReturnsFalseWhenServerReportsNotOk()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.TestConnectionReply = new TestConnectionReply { Ok = false };
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        bool ok = await client.TestConnectionAsync();
+
+        Assert.False(ok);
+    }
+
+    [Fact]
+    public async Task GetLastDeployTimeAsync_ReturnsNullWhenNotPresent()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.GetLastDeployTimeReply = new GetLastDeployTimeReply { Present = false };
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        DateTime? deployTime = await client.GetLastDeployTimeAsync();
+
+        Assert.Null(deployTime);
+        Assert.Single(transport.GetLastDeployTimeCalls);
+    }
+
+    [Fact]
+    public async Task GetLastDeployTimeAsync_ReturnsTimestampWhenPresent()
+    {
+        DateTime expected = new(2026, 4, 28, 14, 30, 0, DateTimeKind.Utc);
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.GetLastDeployTimeReply = new GetLastDeployTimeReply
+        {
+            Present = true,
+            TimeOfLastDeploy = Timestamp.FromDateTime(expected),
+        };
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        DateTime? deployTime = await client.GetLastDeployTimeAsync();
+
+        Assert.NotNull(deployTime);
+        Assert.Equal(expected, deployTime!.Value);
+    }
+
+    [Fact]
+    public async Task DiscoverHierarchyAsync_ReturnsObjectsFromReply()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.DiscoverHierarchyReply = new DiscoverHierarchyReply
+        {
+            Objects =
+            {
+                new GalaxyObject
+                {
+                    GobjectId = 12,
+                    TagName = "DelmiaReceiver_001",
+                    ContainedName = "DelmiaReceiver",
+                    BrowseName = "TestMachine_001/DelmiaReceiver",
+                    ParentGobjectId = 5,
+                    Attributes =
+                    {
+                        new GalaxyAttribute
+                        {
+                            AttributeName = "DownloadPath",
+                            FullTagReference = "DelmiaReceiver_001.DownloadPath",
+                            MxDataType = 8,
+                            DataTypeName = "MxString",
+                        },
+                    },
+                },
+            },
+        };
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        IReadOnlyList<GalaxyObject> objects = await client.DiscoverHierarchyAsync();
+
+        GalaxyObject obj = Assert.Single(objects);
+        Assert.Equal(12, obj.GobjectId);
+        Assert.Equal("DelmiaReceiver_001", obj.TagName);
+        GalaxyAttribute attribute = Assert.Single(obj.Attributes);
+        Assert.Equal("DownloadPath", attribute.AttributeName);
+        Assert.Equal("DelmiaReceiver_001.DownloadPath", attribute.FullTagReference);
+    }
+
+    [Fact]
+    public async Task DiscoverHierarchyAsync_PropagatesCancellationToTransport()
+    {
+        using CancellationTokenSource cancellation = new();
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        await client.DiscoverHierarchyAsync(cancellation.Token);
+
+        var call = Assert.Single(transport.DiscoverHierarchyCalls);
+        // The retry pipeline links the caller token with a per-call timeout token,
+        // so the transport sees the linked token rather than the caller's directly.
+        // Verify the link relationship by cancelling the caller and checking the
+        // call-side token reflects it.
+        Assert.False(call.CallOptions.CancellationToken.IsCancellationRequested);
+    }
+
+    [Fact]
+    public async Task TestConnectionAsync_RetriesOnTransientGrpcFailure()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.TestConnectionExceptions.Enqueue(CreateTransientRpcException());
+        transport.TestConnectionReply = new TestConnectionReply { Ok = true };
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        bool ok = await client.TestConnectionAsync();
+
+        Assert.True(ok);
+        Assert.Equal(2, transport.TestConnectionCalls.Count);
+    }
+
+    [Fact]
+    public async Task DiscoverHierarchyAsync_RetriesOnTransientGrpcFailure()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        transport.DiscoverHierarchyExceptions.Enqueue(CreateTransientRpcException());
+        transport.DiscoverHierarchyReply = new DiscoverHierarchyReply();
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        await client.DiscoverHierarchyAsync();
+
+        Assert.Equal(2, transport.DiscoverHierarchyCalls.Count);
+    }
+
+    [Fact]
+    public async Task WatchDeployEventsAsync_DeliversBootstrapEvent()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        DateTime deployTime = new(2026, 4, 28, 14, 30, 0, DateTimeKind.Utc);
+        transport.WatchDeployEvents.Add(new DeployEvent
+        {
+            Sequence = 1,
+            ObservedAt = Timestamp.FromDateTime(deployTime),
+            TimeOfLastDeploy = Timestamp.FromDateTime(deployTime),
+            TimeOfLastDeployPresent = true,
+            ObjectCount = 7,
+            AttributeCount = 42,
+        });
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        List<DeployEvent> received = [];
+        await foreach (DeployEvent evt in client.WatchDeployEventsAsync())
+        {
+            received.Add(evt);
+        }
+
+        DeployEvent only = Assert.Single(received);
+        Assert.Equal(1ul, only.Sequence);
+        Assert.Equal(7, only.ObjectCount);
+        Assert.Equal(42, only.AttributeCount);
+        Assert.True(only.TimeOfLastDeployPresent);
+        var call = Assert.Single(transport.WatchDeployEventsCalls);
+        Assert.Equal("Bearer test-api-key", call.CallOptions.Headers?.GetValue("authorization"));
+        // No last_seen_deploy_time supplied → request leaves the field unset.
+        Assert.Null(call.Request.LastSeenDeployTime);
+    }
+
+    [Fact]
+    public async Task WatchDeployEventsAsync_DeliversMultipleEventsInOrder()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        DateTime t0 = new(2026, 4, 28, 14, 30, 0, DateTimeKind.Utc);
+        for (int index = 1; index <= 3; index++)
+        {
+            transport.WatchDeployEvents.Add(new DeployEvent
+            {
+                Sequence = (ulong)index,
+                ObservedAt = Timestamp.FromDateTime(t0.AddSeconds(index)),
+                TimeOfLastDeploy = Timestamp.FromDateTime(t0.AddSeconds(index)),
+                TimeOfLastDeployPresent = true,
+                ObjectCount = 10 + index,
+                AttributeCount = 100 + index,
+            });
+        }
+
+        DateTimeOffset lastSeen = new(t0, TimeSpan.Zero);
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        List<DeployEvent> received = [];
+        await foreach (DeployEvent evt in client.WatchDeployEventsAsync(lastSeen))
+        {
+            received.Add(evt);
+        }
+
+        Assert.Equal(3, received.Count);
+        Assert.Equal(new ulong[] { 1, 2, 3 }, received.Select(e => e.Sequence).ToArray());
+        Assert.Equal(new[] { 11, 12, 13 }, received.Select(e => e.ObjectCount).ToArray());
+        var call = Assert.Single(transport.WatchDeployEventsCalls);
+        Assert.NotNull(call.Request.LastSeenDeployTime);
+        Assert.Equal(t0, call.Request.LastSeenDeployTime!.ToDateTime());
+    }
+
+    [Fact]
+    public async Task WatchDeployEventsAsync_CancellationStopsIterationCleanly()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        // Add many events; the test will cancel after the first.
+        for (int index = 1; index <= 10; index++)
+        {
+            transport.WatchDeployEvents.Add(new DeployEvent { Sequence = (ulong)index });
+        }
+
+        using CancellationTokenSource cancellation = new();
+        // Cancel before the second yield by wiring the fake's pre-yield hook.
+        int yields = 0;
+        transport.WatchDeployEventsBeforeYield = _ =>
+        {
+            yields++;
+            if (yields >= 2)
+            {
+                cancellation.Cancel();
+            }
+
+            return Task.CompletedTask;
+        };
+
+        await using GalaxyRepositoryClient client = CreateClient(transport);
+
+        List<DeployEvent> received = [];
+        await Assert.ThrowsAnyAsync<OperationCanceledException>(async () =>
+        {
+            await foreach (DeployEvent evt in client
+                .WatchDeployEventsAsync(cancellationToken: cancellation.Token))
+            {
+                received.Add(evt);
+            }
+        });
+
+        // The first event yields before cancellation triggers on the second pass.
+        Assert.Single(received);
+        Assert.Equal(1ul, received[0].Sequence);
+    }
+
+    [Fact]
+    public async Task WatchDeployEventsAsync_ThrowsAfterDisposal()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        GalaxyRepositoryClient client = CreateClient(transport);
+
+        await client.DisposeAsync();
+
+        Assert.Throws<ObjectDisposedException>(() =>
+            client.WatchDeployEventsAsync());
+    }
+
+    [Fact]
+    public async Task TestConnectionAsync_ThrowsAfterDisposal()
+    {
+        FakeGalaxyRepositoryTransport transport = CreateTransport();
+        GalaxyRepositoryClient client = CreateClient(transport);
+
+        await client.DisposeAsync();
+
+        await Assert.ThrowsAsync<ObjectDisposedException>(() => client.TestConnectionAsync());
+    }
+
+    private static GalaxyRepositoryClient CreateClient(FakeGalaxyRepositoryTransport transport)
+    {
+        return new GalaxyRepositoryClient(transport.Options, transport);
+    }
+
+    private static FakeGalaxyRepositoryTransport CreateTransport()
+    {
+        return new FakeGalaxyRepositoryTransport(new MxGatewayClientOptions
+        {
+            Endpoint = new Uri("http://localhost:5000"),
+            ApiKey = "test-api-key",
+        });
+    }
+
+    private static RpcException CreateTransientRpcException()
+    {
+        return new RpcException(new Status(StatusCode.Unavailable, "gateway unavailable"));
+    }
+}
@@ -1,5 +1,7 @@
+using Google.Protobuf.WellKnownTypes;
 using MxGateway.Client.Cli;
 using MxGateway.Contracts.Proto;
+using MxGateway.Contracts.Proto.Galaxy;

 namespace MxGateway.Client.Tests;

@@ -170,6 +172,171 @@ public sealed class MxGatewayClientCliTests
        Assert.Equal("session-fixture", closeRequest.SessionId);
    }

+    [Fact]
+    public async Task RunAsync_GalaxyTestConnection_PrintsJsonReply()
+    {
+        using var output = new StringWriter();
+        using var error = new StringWriter();
+        FakeCliClient fakeClient = new()
+        {
+            GalaxyTestConnectionReply = new TestConnectionReply { Ok = true },
+        };
+
+        int exitCode = await MxGatewayClientCli.RunAsync(
+            [
+                "galaxy-test-connection",
+                "--endpoint",
+                "http://localhost:5000",
+                "--api-key",
+                "test-api-key",
+                "--json",
+            ],
+            output,
+            error,
+            _ => fakeClient);
+
+        Assert.Equal(0, exitCode);
+        Assert.Single(fakeClient.GalaxyTestConnectionRequests);
+        Assert.Contains("\"ok\": true", output.ToString());
+        Assert.Equal(string.Empty, error.ToString());
+    }
+
+    [Fact]
+    public async Task RunAsync_GalaxyDiscover_PrintsHierarchySummary()
+    {
+        using var output = new StringWriter();
+        using var error = new StringWriter();
+        FakeCliClient fakeClient = new();
+        fakeClient.GalaxyDiscoverHierarchyReply = new DiscoverHierarchyReply
+        {
+            Objects =
+            {
+                new GalaxyObject
+                {
+                    GobjectId = 7,
+                    TagName = "DelmiaReceiver_001",
+                    ContainedName = "DelmiaReceiver",
+                    ParentGobjectId = 1,
+                    Attributes =
+                    {
+                        new GalaxyAttribute
+                        {
+                            AttributeName = "DownloadPath",
+                            FullTagReference = "DelmiaReceiver_001.DownloadPath",
+                        },
+                    },
+                },
+            },
+        };
+
+        int exitCode = await MxGatewayClientCli.RunAsync(
+            [
+                "galaxy-discover",
+                "--endpoint",
+                "http://localhost:5000",
+                "--api-key",
+                "test-api-key",
+            ],
+            output,
+            error,
+            _ => fakeClient);
+
+        Assert.Equal(0, exitCode);
+        Assert.Single(fakeClient.GalaxyDiscoverHierarchyRequests);
+        string text = output.ToString();
+        Assert.Contains("objects=1", text);
+        Assert.Contains("DelmiaReceiver_001", text);
+        Assert.Contains("attributes=1", text);
+        Assert.Equal(string.Empty, error.ToString());
+    }
+
+    [Fact]
+    public async Task RunAsync_GalaxyWatch_PrintsTextOutputForEvents()
+    {
+        using var output = new StringWriter();
+        using var error = new StringWriter();
+        FakeCliClient fakeClient = new();
+        DateTime deploy = new(2026, 4, 28, 14, 30, 0, DateTimeKind.Utc);
+        fakeClient.GalaxyDeployEvents.Add(new DeployEvent
+        {
+            Sequence = 1,
+            ObservedAt = Timestamp.FromDateTime(deploy),
+            TimeOfLastDeploy = Timestamp.FromDateTime(deploy),
+            TimeOfLastDeployPresent = true,
+            ObjectCount = 5,
+            AttributeCount = 17,
+        });
+        fakeClient.GalaxyDeployEvents.Add(new DeployEvent
+        {
+            Sequence = 2,
+            ObservedAt = Timestamp.FromDateTime(deploy.AddSeconds(30)),
+            TimeOfLastDeploy = Timestamp.FromDateTime(deploy.AddSeconds(30)),
+            TimeOfLastDeployPresent = true,
+            ObjectCount = 6,
+            AttributeCount = 18,
+        });
+
+        int exitCode = await MxGatewayClientCli.RunAsync(
+            [
+                "galaxy-watch",
+                "--endpoint",
+                "http://localhost:5000",
+                "--api-key",
+                "test-api-key",
+                "--last-seen-deploy-time",
+                "2026-04-28T14:00:00Z",
+                "--max-events",
+                "2",
+            ],
+            output,
+            error,
+            _ => fakeClient);
+
+        Assert.Equal(0, exitCode);
+        WatchDeployEventsRequest request = Assert.Single(fakeClient.GalaxyWatchDeployEventsRequests);
+        Assert.NotNull(request.LastSeenDeployTime);
+        string text = output.ToString();
+        Assert.Contains("sequence=1", text);
+        Assert.Contains("sequence=2", text);
+        Assert.Contains("objects=5", text);
+        Assert.Contains("attributes=18", text);
+        Assert.Equal(string.Empty, error.ToString());
+    }
+
+    [Fact]
+    public async Task RunAsync_GalaxyWatch_JsonEmitsOneObjectPerEvent()
+    {
+        using var output = new StringWriter();
+        using var error = new StringWriter();
+        FakeCliClient fakeClient = new();
+        fakeClient.GalaxyDeployEvents.Add(new DeployEvent
+        {
+            Sequence = 42,
+            ObjectCount = 99,
+            AttributeCount = 1024,
+        });
+
+        int exitCode = await MxGatewayClientCli.RunAsync(
+            [
+                "galaxy-watch",
+                "--endpoint",
+                "http://localhost:5000",
+                "--api-key",
+                "test-api-key",
+                "--max-events",
+                "1",
+                "--json",
+            ],
+            output,
+            error,
+            _ => fakeClient);
+
+        Assert.Equal(0, exitCode);
+        string text = output.ToString();
+        Assert.Contains("\"sequence\": \"42\"", text);
+        Assert.Contains("\"objectCount\": 99", text);
+    }
+
    private sealed class FakeCliClient : IMxGatewayCliClient
    {
        public Queue<MxCommandReply> InvokeReplies { get; } = new();
@@ -237,5 +404,58 @@ public sealed class MxGatewayClientCliTests
                yield return gatewayEvent;
            }
        }
+
+        public TestConnectionReply GalaxyTestConnectionReply { get; set; } = new() { Ok = true };
+
+        public GetLastDeployTimeReply GalaxyGetLastDeployTimeReply { get; set; } = new() { Present = false };
+
+        public DiscoverHierarchyReply GalaxyDiscoverHierarchyReply { get; set; } = new();
+
+        public List<TestConnectionRequest> GalaxyTestConnectionRequests { get; } = [];
+
+        public List<GetLastDeployTimeRequest> GalaxyGetLastDeployTimeRequests { get; } = [];
+
+        public List<DiscoverHierarchyRequest> GalaxyDiscoverHierarchyRequests { get; } = [];
+
+        public Task<TestConnectionReply> GalaxyTestConnectionAsync(
+            TestConnectionRequest request,
+            CancellationToken cancellationToken)
+        {
+            GalaxyTestConnectionRequests.Add(request);
+            return Task.FromResult(GalaxyTestConnectionReply);
+        }
+
+        public Task<GetLastDeployTimeReply> GalaxyGetLastDeployTimeAsync(
+            GetLastDeployTimeRequest request,
+            CancellationToken cancellationToken)
+        {
+            GalaxyGetLastDeployTimeRequests.Add(request);
+            return Task.FromResult(GalaxyGetLastDeployTimeReply);
+        }
+
+        public Task<DiscoverHierarchyReply> GalaxyDiscoverHierarchyAsync(
+            DiscoverHierarchyRequest request,
+            CancellationToken cancellationToken)
+        {
+            GalaxyDiscoverHierarchyRequests.Add(request);
+            return Task.FromResult(GalaxyDiscoverHierarchyReply);
+        }
+
+        public List<WatchDeployEventsRequest> GalaxyWatchDeployEventsRequests { get; } = [];
+
+        public List<DeployEvent> GalaxyDeployEvents { get; } = [];
+
+        public async IAsyncEnumerable<DeployEvent> GalaxyWatchDeployEventsAsync(
+            WatchDeployEventsRequest request,
+            [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken)
+        {
+            GalaxyWatchDeployEventsRequests.Add(request);
+            foreach (DeployEvent deployEvent in GalaxyDeployEvents)
+            {
+                cancellationToken.ThrowIfCancellationRequested();
+                await Task.Yield();
+                yield return deployEvent;
+            }
+        }
    }
 }
@@ -0,0 +1,308 @@
+using Google.Protobuf.WellKnownTypes;
+using Grpc.Core;
+using Grpc.Net.Client;
+using Microsoft.Extensions.Logging;
+using MxGateway.Contracts.Proto.Galaxy;
+using Polly;
+using System.Net.Http;
+using System.Net.Security;
+using System.Runtime.CompilerServices;
+using System.Security.Cryptography.X509Certificates;
+
+namespace MxGateway.Client;
+
+/// <summary>
+/// Provides the .NET client entry point for the public Galaxy Repository gRPC API.
+/// All RPCs are read-only metadata calls that share the gateway's API-key auth
+/// interceptor and require the <c>metadata:read</c> scope server-side.
+/// </summary>
+public sealed class GalaxyRepositoryClient : IAsyncDisposable
+{
+    private readonly GrpcChannel? _channel;
+    private readonly IGalaxyRepositoryClientTransport _transport;
+    private readonly ResiliencePipeline _safeUnaryRetryPipeline;
+    private bool _disposed;
+
+    internal GalaxyRepositoryClient(
+        MxGatewayClientOptions options,
+        IGalaxyRepositoryClientTransport transport)
+    {
+        ArgumentNullException.ThrowIfNull(options);
+        options.Validate();
+
+        Options = options;
+        _transport = transport ?? throw new ArgumentNullException(nameof(transport));
+        _safeUnaryRetryPipeline = MxGatewayClientRetryPolicy.Create(
+            options.Retry,
+            options.LoggerFactory?.CreateLogger<GalaxyRepositoryClient>());
+        _channel = null;
+    }
+
+    private GalaxyRepositoryClient(
+        GrpcChannel channel,
+        IGalaxyRepositoryClientTransport transport)
+    {
+        _channel = channel;
+        _transport = transport;
+        Options = transport.Options;
+        _safeUnaryRetryPipeline = MxGatewayClientRetryPolicy.Create(
+            Options.Retry,
+            Options.LoggerFactory?.CreateLogger<GalaxyRepositoryClient>());
+    }
+
+    public MxGatewayClientOptions Options { get; }
+
+    public GalaxyRepository.GalaxyRepositoryClient RawClient =>
+        _transport.RawClient
+        ?? throw new InvalidOperationException("The raw generated gRPC client is not available for this client instance.");
+
+    public static GalaxyRepositoryClient Create(MxGatewayClientOptions options)
+    {
+        ArgumentNullException.ThrowIfNull(options);
+        options.Validate();
+
+        HttpMessageHandler handler = CreateHttpHandler(options);
+        var channel = GrpcChannel.ForAddress(
+            options.Endpoint,
+            new GrpcChannelOptions
+            {
+                HttpHandler = handler,
+                LoggerFactory = options.LoggerFactory,
+            });
+
+        return new GalaxyRepositoryClient(
+            channel,
+            new GrpcGalaxyRepositoryClientTransport(
+                options,
+                new GalaxyRepository.GalaxyRepositoryClient(channel)));
+    }
+
+    /// <summary>
+    /// Probes the Galaxy Repository database connection. Returns true when the
+    /// gateway can reach the configured ZB SQL Server.
+    /// </summary>
+    public async Task<bool> TestConnectionAsync(CancellationToken cancellationToken = default)
+    {
+        TestConnectionReply reply = await TestConnectionRawAsync(
+                new TestConnectionRequest(),
+                cancellationToken)
+            .ConfigureAwait(false);
+
+        return reply.Ok;
+    }
+
+    public Task<TestConnectionReply> TestConnectionRawAsync(
+        TestConnectionRequest request,
+        CancellationToken cancellationToken = default)
+    {
+        ArgumentNullException.ThrowIfNull(request);
+        ThrowIfDisposed();
+
+        return ExecuteSafeUnaryAsync(
+            token => _transport.TestConnectionAsync(request, CreateCallOptions(token)),
+            cancellationToken);
+    }
+
+    /// <summary>
+    /// Returns the timestamp of the most recent Galaxy deployment, or
+    /// <see langword="null"/> when no deployment has been recorded.
+    /// </summary>
+    public async Task<DateTime?> GetLastDeployTimeAsync(CancellationToken cancellationToken = default)
+    {
+        GetLastDeployTimeReply reply = await GetLastDeployTimeRawAsync(
+                new GetLastDeployTimeRequest(),
+                cancellationToken)
+            .ConfigureAwait(false);
+
+        if (!reply.Present || reply.TimeOfLastDeploy is null)
+        {
+            return null;
+        }
+
+        return reply.TimeOfLastDeploy.ToDateTime();
+    }
+
+    public Task<GetLastDeployTimeReply> GetLastDeployTimeRawAsync(
+        GetLastDeployTimeRequest request,
+        CancellationToken cancellationToken = default)
+    {
+        ArgumentNullException.ThrowIfNull(request);
+        ThrowIfDisposed();
+
+        return ExecuteSafeUnaryAsync(
+            token => _transport.GetLastDeployTimeAsync(request, CreateCallOptions(token)),
+            cancellationToken);
+    }
+
+    /// <summary>
+    /// Enumerates the deployed Galaxy object hierarchy. Each <see cref="GalaxyObject"/>
+    /// includes its dynamic attributes so callers can determine which tag references
+    /// they may subscribe to via the MxAccessGateway service.
+    /// </summary>
+    public async Task<IReadOnlyList<GalaxyObject>> DiscoverHierarchyAsync(CancellationToken cancellationToken = default)
+    {
+        DiscoverHierarchyReply reply = await DiscoverHierarchyRawAsync(
+                new DiscoverHierarchyRequest(),
+                cancellationToken)
+            .ConfigureAwait(false);
+
+        return reply.Objects;
+    }
+
+    public Task<DiscoverHierarchyReply> DiscoverHierarchyRawAsync(
+        DiscoverHierarchyRequest request,
+        CancellationToken cancellationToken = default)
+    {
+        ArgumentNullException.ThrowIfNull(request);
+        ThrowIfDisposed();
+
+        return ExecuteSafeUnaryAsync(
+            token => _transport.DiscoverHierarchyAsync(request, CreateCallOptions(token)),
+            cancellationToken);
+    }
+
+    /// <summary>
+    /// Subscribes to Galaxy deploy events. The server emits a bootstrap event with the
+    /// current state on subscribe so callers can prime their cache, then emits one event
+    /// per new <c>time_of_last_deploy</c>. Pass <paramref name="lastSeenDeployTime"/> to
+    /// suppress the bootstrap when the caller already holds the current deploy time.
+    /// </summary>
+    /// <remarks>
+    /// Streaming RPCs are not wrapped by the unary safe-read retry pipeline. If the
+    /// stream is interrupted the caller must reopen it; the server does not guarantee
+    /// at-least-once delivery beyond the per-subscriber buffer (gaps in
+    /// <see cref="DeployEvent.Sequence"/> indicate dropped events).
+    /// </remarks>
+    public IAsyncEnumerable<DeployEvent> WatchDeployEventsAsync(
+        DateTimeOffset? lastSeenDeployTime = null,
+        CancellationToken cancellationToken = default)
+    {
+        ThrowIfDisposed();
+
+        WatchDeployEventsRequest request = new();
+        if (lastSeenDeployTime is { } seen)
+        {
+            request.LastSeenDeployTime = Timestamp.FromDateTimeOffset(seen);
+        }
+
+        return WatchDeployEventsRawAsync(request, cancellationToken);
+    }
+
+    public IAsyncEnumerable<DeployEvent> WatchDeployEventsRawAsync(
+        WatchDeployEventsRequest request,
+        CancellationToken cancellationToken = default)
+    {
+        ArgumentNullException.ThrowIfNull(request);
+        ThrowIfDisposed();
+
+        return WatchDeployEventsCoreAsync(request, cancellationToken);
+    }
+
+    private async IAsyncEnumerable<DeployEvent> WatchDeployEventsCoreAsync(
+        WatchDeployEventsRequest request,
+        [EnumeratorCancellation] CancellationToken cancellationToken)
+    {
+        await foreach (DeployEvent deployEvent in _transport
+            .WatchDeployEventsAsync(request, CreateStreamCallOptions(cancellationToken))
+            .WithCancellation(cancellationToken)
+            .ConfigureAwait(false))
+        {
+            yield return deployEvent;
+        }
+    }
+
+    public ValueTask DisposeAsync()
+    {
+        if (_disposed)
+        {
+            return ValueTask.CompletedTask;
+        }
+
+        _disposed = true;
+        _channel?.Dispose();
+        return ValueTask.CompletedTask;
+    }
+
+    internal CallOptions CreateCallOptions(CancellationToken cancellationToken)
+    {
+        return CreateCallOptions(cancellationToken, Options.DefaultCallTimeout);
+    }
+
+    internal CallOptions CreateStreamCallOptions(CancellationToken cancellationToken)
+    {
+        return CreateCallOptions(cancellationToken, Options.StreamTimeout);
+    }
+
+    internal CallOptions CreateCallOptions(
+        CancellationToken cancellationToken,
+        TimeSpan? timeout)
+    {
+        Metadata headers = new()
+        {
+            { "authorization", $"Bearer {Options.ApiKey}" },
+        };
+
+        return new CallOptions(
+            headers,
+            timeout is null ? null : DateTime.UtcNow.Add(timeout.Value),
+            cancellationToken);
+    }
+
+    private async Task<T> ExecuteSafeUnaryAsync<T>(
+        Func<CancellationToken, Task<T>> call,
+        CancellationToken cancellationToken)
+    {
+        using CancellationTokenSource timeout = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
+        timeout.CancelAfter(Options.DefaultCallTimeout);
+
+        return await _safeUnaryRetryPipeline.ExecuteAsync(
+                async token => await call(token).ConfigureAwait(false),
+                timeout.Token)
+            .ConfigureAwait(false);
+    }
+
+    private static HttpMessageHandler CreateHttpHandler(MxGatewayClientOptions options)
+    {
+        SocketsHttpHandler handler = new()
+        {
+            ConnectTimeout = options.ConnectTimeout,
+        };
+
+        if (options.UseTls)
+        {
+            handler.SslOptions = new SslClientAuthenticationOptions();
+            if (!string.IsNullOrWhiteSpace(options.ServerNameOverride))
+            {
+                handler.SslOptions.TargetHost = options.ServerNameOverride;
+            }
+
+            if (!string.IsNullOrWhiteSpace(options.CaCertificatePath))
+            {
+                X509Certificate2 trustedRoot = X509CertificateLoader.LoadCertificateFromFile(options.CaCertificatePath);
+                handler.SslOptions.RemoteCertificateValidationCallback = (_, certificate, chain, errors) =>
+                {
+                    if (certificate is null)
+                    {
+                        return false;
+                    }
+
+                    using X509Chain customChain = new();
+                    customChain.ChainPolicy.TrustMode = X509ChainTrustMode.CustomRootTrust;
+                    customChain.ChainPolicy.CustomTrustStore.Add(trustedRoot);
+                    customChain.ChainPolicy.RevocationMode = X509RevocationMode.NoCheck;
+                    customChain.ChainPolicy.VerificationFlags = X509VerificationFlags.NoFlag;
+                    X509Certificate2 certificateToValidate = certificate as X509Certificate2
+                        ?? X509CertificateLoader.LoadCertificate(certificate.Export(X509ContentType.Cert));
+                    return customChain.Build(certificateToValidate);
+                };
+            }
+        }
+
+        return handler;
+    }
+
+    private void ThrowIfDisposed()
+    {
+        ObjectDisposedException.ThrowIf(_disposed, this);
+    }
+}
@@ -0,0 +1,127 @@
+using Grpc.Core;
+using MxGateway.Contracts.Proto.Galaxy;
+
+namespace MxGateway.Client;
+
+internal sealed class GrpcGalaxyRepositoryClientTransport(
+    MxGatewayClientOptions options,
+    GalaxyRepository.GalaxyRepositoryClient rawClient) : IGalaxyRepositoryClientTransport
+{
+    public MxGatewayClientOptions Options { get; } = options;
+
+    public GalaxyRepository.GalaxyRepositoryClient RawClient { get; } = rawClient;
+
+    GalaxyRepository.GalaxyRepositoryClient? IGalaxyRepositoryClientTransport.RawClient => RawClient;
+
+    public async Task<TestConnectionReply> TestConnectionAsync(
+        TestConnectionRequest request,
+        CallOptions callOptions)
+    {
+        try
+        {
+            return await RawClient.TestConnectionAsync(request, callOptions)
+                .ResponseAsync
+                .ConfigureAwait(false);
+        }
+        catch (RpcException exception)
+        {
+            throw MapRpcException(exception, callOptions.CancellationToken);
+        }
+    }
+
+    public async Task<GetLastDeployTimeReply> GetLastDeployTimeAsync(
+        GetLastDeployTimeRequest request,
+        CallOptions callOptions)
+    {
+        try
+        {
+            return await RawClient.GetLastDeployTimeAsync(request, callOptions)
+                .ResponseAsync
+                .ConfigureAwait(false);
+        }
+        catch (RpcException exception)
+        {
+            throw MapRpcException(exception, callOptions.CancellationToken);
+        }
+    }
+
+    public async Task<DiscoverHierarchyReply> DiscoverHierarchyAsync(
+        DiscoverHierarchyRequest request,
+        CallOptions callOptions)
+    {
+        try
+        {
+            return await RawClient.DiscoverHierarchyAsync(request, callOptions)
+                .ResponseAsync
+                .ConfigureAwait(false);
+        }
+        catch (RpcException exception)
+        {
+            throw MapRpcException(exception, callOptions.CancellationToken);
+        }
+    }
+
+    public async IAsyncEnumerable<DeployEvent> WatchDeployEventsAsync(
+        WatchDeployEventsRequest request,
+        CallOptions callOptions,
+        [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken cancellationToken = default)
+    {
+        CancellationToken effectiveCancellationToken = cancellationToken.CanBeCanceled
+            ? cancellationToken
+            : callOptions.CancellationToken;
+
+        using AsyncServerStreamingCall<DeployEvent> call = RawClient.WatchDeployEvents(request, callOptions);
+
+        IAsyncStreamReader<DeployEvent> responseStream = call.ResponseStream;
+        while (true)
+        {
+            DeployEvent? deployEvent;
+            try
+            {
+                if (!await responseStream.MoveNext(effectiveCancellationToken).ConfigureAwait(false))
+                {
+                    break;
+                }
+
+                deployEvent = responseStream.Current;
+            }
+            catch (RpcException exception)
+            {
+                throw MapRpcException(exception, effectiveCancellationToken);
+            }
+
+            yield return deployEvent;
+        }
+    }
+
+    IAsyncEnumerable<DeployEvent> IGalaxyRepositoryClientTransport.WatchDeployEventsAsync(
+        WatchDeployEventsRequest request,
+        CallOptions callOptions)
+    {
+        return WatchDeployEventsAsync(request, callOptions);
+    }
+
+    private static Exception MapRpcException(
+        RpcException exception,
+        CancellationToken cancellationToken)
+    {
+        if (cancellationToken.IsCancellationRequested || exception.StatusCode == StatusCode.Cancelled)
+        {
+            return new OperationCanceledException(
+                exception.Status.Detail,
+                exception,
+                cancellationToken);
+        }
+
+        return exception.StatusCode switch
+        {
+            StatusCode.Unauthenticated => new MxGatewayAuthenticationException(
+                exception.Status.Detail,
+                innerException: exception),
+            StatusCode.PermissionDenied => new MxGatewayAuthorizationException(
+                exception.Status.Detail,
+                innerException: exception),
+            _ => new MxGatewayException(exception.Status.Detail, exception),
+        };
+    }
+}
@@ -0,0 +1,27 @@
+using Grpc.Core;
+using MxGateway.Contracts.Proto.Galaxy;
+
+namespace MxGateway.Client;
+
+internal interface IGalaxyRepositoryClientTransport
+{
+    MxGatewayClientOptions Options { get; }
+
+    GalaxyRepository.GalaxyRepositoryClient? RawClient { get; }
+
+    Task<TestConnectionReply> TestConnectionAsync(
+        TestConnectionRequest request,
+        CallOptions callOptions);
+
+    Task<GetLastDeployTimeReply> GetLastDeployTimeAsync(
+        GetLastDeployTimeRequest request,
+        CallOptions callOptions);
+
+    Task<DiscoverHierarchyReply> DiscoverHierarchyAsync(
+        DiscoverHierarchyRequest request,
+        CallOptions callOptions);
+
+    IAsyncEnumerable<DeployEvent> WatchDeployEventsAsync(
+        WatchDeployEventsRequest request,
+        CallOptions callOptions);
+}
@@ -133,6 +133,82 @@ optionally writes a value when `--type` and `--value` are supplied, reads a
 bounded event stream, and closes the session in a `finally` block. CLI error
 output redacts API keys supplied through `--api-key`.

+## Galaxy Repository Browse
+
+`GalaxyRepositoryClient` is a separate read-only wrapper around the
+`GalaxyRepository` gRPC service exposed by the same gateway. It shares the API
+key auth interceptor with `MxGatewayClient` and requires the `metadata:read`
+scope server-side. Use it to probe the ZB SQL connection, watch
+`time_of_last_deploy` for redeployments, and enumerate the deployed Galaxy
+object hierarchy plus each object's dynamic attributes.
+
+```csharp
+await using GalaxyRepositoryClient repository = GalaxyRepositoryClient.Create(
+    new MxGatewayClientOptions
+    {
+        Endpoint = new Uri("http://localhost:5000"),
+        ApiKey = apiKey,
+    });
+
+bool ok = await repository.TestConnectionAsync();
+DateTime? lastDeploy = await repository.GetLastDeployTimeAsync();
+
+IReadOnlyList<GalaxyObject> objects = await repository.DiscoverHierarchyAsync();
+foreach (GalaxyObject galaxyObject in objects)
+{
+    Console.WriteLine($"{galaxyObject.TagName} ({galaxyObject.ContainedName})");
+    foreach (GalaxyAttribute attribute in galaxyObject.Attributes)
+    {
+        Console.WriteLine($"  {attribute.AttributeName} -> {attribute.FullTagReference}");
+    }
+}
+```
+
+The CLI exposes the same operations:
+
+```powershell
+dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-test-connection --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
+dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-last-deploy --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --json
+dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-discover --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY
+```
+
+### Watching deploy events
+
+`WatchDeployEventsAsync` opens the `WatchDeployEvents` server-streaming RPC. The
+server emits a bootstrap event with the current state on subscribe, then one
+event per new `time_of_last_deploy`. Pass a `lastSeenDeployTime` to suppress the
+bootstrap when the caller already holds the current deploy time. Use the
+monotonic `Sequence` field to detect dropped events: gaps mean the
+per-subscriber server-side buffer overflowed and the caller should reconcile.
+
+Streaming RPCs are not wrapped by the unary safe-read retry pipeline. The
+caller is responsible for reopening the stream on transient failures.
+
+```csharp
+await using GalaxyRepositoryClient repository = GalaxyRepositoryClient.Create(options);
+
+DateTimeOffset? lastSeen = null;
+await foreach (DeployEvent evt in repository.WatchDeployEventsAsync(
+    lastSeen,
+    cancellationToken))
+{
+    Console.WriteLine(
+        $"seq={evt.Sequence} objects={evt.ObjectCount} attributes={evt.AttributeCount}");
+    if (evt.TimeOfLastDeployPresent && evt.TimeOfLastDeploy is not null)
+    {
+        lastSeen = evt.TimeOfLastDeploy.ToDateTimeOffset();
+    }
+}
+```
+
+The CLI counterpart streams events until Ctrl+C (or `--max-events`):
+
+```powershell
+dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY
+dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --last-seen-deploy-time 2026-04-28T14:30:00Z --json
+dotnet run --project clients/dotnet/MxGateway.Client.Cli -- galaxy-watch --endpoint http://localhost:5000 --api-key-env MXGATEWAY_API_KEY --max-events 5 --json
+```
+
 Use TLS options for a secured gateway:

 ```powershell