diff --git a/src/Runner.Common/Constants.cs b/src/Runner.Common/Constants.cs
index 7a1f1cbb0a1..b07d60d39fc 100644
--- a/src/Runner.Common/Constants.cs
+++ b/src/Runner.Common/Constants.cs
@@ -179,6 +179,7 @@ public static class Features
public static readonly string EmitCompositeMarkers = "actions_runner_emit_composite_markers";
public static readonly string BatchActionResolution = "actions_batch_action_resolution";
public static readonly string UseBearerTokenForCodeload = "actions_use_bearer_token_for_codeload";
+ public static readonly string OverrideDebuggerWelcomeMessage = "actions_runner_override_debugger_welcome_message";
}
// Node version migration related constants
diff --git a/src/Runner.Worker/Dap/DapDebugger.cs b/src/Runner.Worker/Dap/DapDebugger.cs
index 9848b872b73..d5dba2fe25d 100644
--- a/src/Runner.Worker/Dap/DapDebugger.cs
+++ b/src/Runner.Worker/Dap/DapDebugger.cs
@@ -63,6 +63,7 @@ public sealed class DapDebugger : RunnerService, IDapDebugger
private volatile DapSessionState _state = DapSessionState.NotStarted;
private CancellationTokenRegistration? _cancellationRegistration;
private bool _isFirstStep = true;
+ private bool _welcomeMessageSent;
// Dev Tunnel relay host for remote debugging
private TunnelRelayTunnelHost _tunnelRelayHost;
@@ -490,6 +491,11 @@ internal async Task HandleMessageAsync(string messageJson, CancellationToken can
});
Trace.Info("Sent initialized event");
}
+
+ if (request.Command == "configurationDone")
+ {
+ SendWelcomeMessage();
+ }
}
catch (Exception ex)
{
@@ -508,6 +514,7 @@ internal async Task HandleMessageAsync(string messageJson, CancellationToken can
internal void HandleClientConnected()
{
_isClientConnected = true;
+ _welcomeMessageSent = false;
Trace.Info("Client connected to debug session");
// If we're paused, re-send the stopped event so the new client
@@ -818,6 +825,34 @@ private void SendOutput(string category, string text)
});
}
+ internal void SendWelcomeMessage()
+ {
+ if (_welcomeMessageSent)
+ {
+ return;
+ }
+ _welcomeMessageSent = true;
+
+ var debuggerConfig = _jobContext?.Global?.Debugger;
+ if (debuggerConfig?.OverrideWelcomeMessage == true)
+ {
+ if (!string.IsNullOrEmpty(debuggerConfig.WelcomeMessage))
+ {
+ SendOutput("console", debuggerConfig.WelcomeMessage);
+ Trace.Info("Sent custom welcome message");
+ }
+ else
+ {
+ Trace.Info("Welcome message suppressed by override");
+ }
+ }
+ else
+ {
+ SendOutput("console", DapReplParser.GetGeneralHelp());
+ Trace.Info("Sent default welcome message");
+ }
+ }
+
internal async Task OnStepStartingAsync(IStep step, bool isFirstStep)
{
bool pauseOnNextStep;
diff --git a/src/Runner.Worker/Dap/DebuggerConfig.cs b/src/Runner.Worker/Dap/DebuggerConfig.cs
index df139a15c18..13106cb563d 100644
--- a/src/Runner.Worker/Dap/DebuggerConfig.cs
+++ b/src/Runner.Worker/Dap/DebuggerConfig.cs
@@ -1,4 +1,4 @@
-using GitHub.DistributedTask.Pipelines;
+using GitHub.DistributedTask.Pipelines;
namespace GitHub.Runner.Worker.Dap
{
@@ -8,10 +8,12 @@ namespace GitHub.Runner.Worker.Dap
///
public sealed class DebuggerConfig
{
- public DebuggerConfig(bool enabled, DebuggerTunnelInfo tunnel)
+ public DebuggerConfig(bool enabled, DebuggerTunnelInfo tunnel, bool overrideWelcomeMessage = false, string welcomeMessage = null)
{
Enabled = enabled;
Tunnel = tunnel;
+ OverrideWelcomeMessage = overrideWelcomeMessage;
+ WelcomeMessage = welcomeMessage;
}
/// Whether the debugger is enabled for this job.
@@ -23,6 +25,19 @@ public DebuggerConfig(bool enabled, DebuggerTunnelInfo tunnel)
///
public DebuggerTunnelInfo Tunnel { get; }
+ ///
+ /// When true, the runner overrides the default welcome message with
+ /// . A null or empty
+ /// suppresses the message entirely. When false, the default help text is shown.
+ ///
+ public bool OverrideWelcomeMessage { get; }
+
+ ///
+ /// Optional welcome message content for the debugger console. Only used when
+ /// is true.
+ ///
+ public string WelcomeMessage { get; }
+
/// Whether the tunnel configuration is complete and valid.
public bool HasValidTunnel => Tunnel != null
&& !string.IsNullOrEmpty(Tunnel.TunnelId)
diff --git a/src/Runner.Worker/ExecutionContext.cs b/src/Runner.Worker/ExecutionContext.cs
index f072335b440..d071790f37d 100644
--- a/src/Runner.Worker/ExecutionContext.cs
+++ b/src/Runner.Worker/ExecutionContext.cs
@@ -970,7 +970,8 @@ public void InitializeJob(Pipelines.AgentJobRequestMessage message, Cancellation
Global.WriteDebug = Global.Variables.Step_Debug ?? false;
// Debugger enabled flag (from acquire response).
- Global.Debugger = new Dap.DebuggerConfig(message.EnableDebugger, message.DebuggerTunnel);
+ var overrideDebuggerWelcomeMessage = Global.Variables.GetBoolean(Constants.Runner.Features.OverrideDebuggerWelcomeMessage) ?? false;
+ Global.Debugger = new Dap.DebuggerConfig(message.EnableDebugger, message.DebuggerTunnel, overrideDebuggerWelcomeMessage, message.DebuggerWelcomeMessage);
// Hook up JobServerQueueThrottling event, we will log warning on server tarpit.
_jobServerQueue.JobServerQueueThrottling += JobServerQueueThrottling_EventReceived;
diff --git a/src/Sdk/DTPipelines/Pipelines/AgentJobRequestMessage.cs b/src/Sdk/DTPipelines/Pipelines/AgentJobRequestMessage.cs
index 96cf07a71c2..782878f79e4 100644
--- a/src/Sdk/DTPipelines/Pipelines/AgentJobRequestMessage.cs
+++ b/src/Sdk/DTPipelines/Pipelines/AgentJobRequestMessage.cs
@@ -267,6 +267,21 @@ public DebuggerTunnelInfo DebuggerTunnel
set;
}
+ ///
+ /// Optional welcome message shown in the debugger console when a client connects.
+ /// Only used when the actions_runner_override_debugger_welcome_message
+ /// feature flag is set to true in the job variables. With the flag set,
+ /// a non-empty value is shown as-is and a null or empty value suppresses the
+ /// default welcome message. When the flag is not set, the runner shows its
+ /// built-in help text and this field is ignored.
+ ///
+ [DataMember(EmitDefaultValue = false)]
+ public string DebuggerWelcomeMessage
+ {
+ get;
+ set;
+ }
+
///
/// Gets the workflow-level action dependencies (lockfile entries)
///
diff --git a/src/Test/L0/Sdk/RSWebApi/AgentJobRequestMessageL0.cs b/src/Test/L0/Sdk/RSWebApi/AgentJobRequestMessageL0.cs
index 1a451d28f12..667c6810e84 100644
--- a/src/Test/L0/Sdk/RSWebApi/AgentJobRequestMessageL0.cs
+++ b/src/Test/L0/Sdk/RSWebApi/AgentJobRequestMessageL0.cs
@@ -1,4 +1,4 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
using System.IO;
using System.Runtime.Serialization.Json;
using System.Text;
@@ -17,13 +17,13 @@ public void VerifyEnableDebuggerDeserialization_WithTrue()
// Arrange
var serializer = new DataContractJsonSerializer(typeof(AgentJobRequestMessage));
string jsonWithEnabledDebugger = DoubleQuotify("{'EnableDebugger': true}");
-
+
// Act
using var stream = new MemoryStream();
stream.Write(Encoding.UTF8.GetBytes(jsonWithEnabledDebugger));
stream.Position = 0;
var recoveredMessage = serializer.ReadObject(stream) as AgentJobRequestMessage;
-
+
// Assert
Assert.NotNull(recoveredMessage);
Assert.True(recoveredMessage.EnableDebugger, "EnableDebugger should be true when JSON contains 'EnableDebugger': true");
@@ -37,13 +37,13 @@ public void VerifyEnableDebuggerDeserialization_DefaultToFalse()
// Arrange
var serializer = new DataContractJsonSerializer(typeof(AgentJobRequestMessage));
string jsonWithoutDebugger = DoubleQuotify("{'messageType': 'PipelineAgentJobRequest'}");
-
+
// Act
using var stream = new MemoryStream();
stream.Write(Encoding.UTF8.GetBytes(jsonWithoutDebugger));
stream.Position = 0;
var recoveredMessage = serializer.ReadObject(stream) as AgentJobRequestMessage;
-
+
// Assert
Assert.NotNull(recoveredMessage);
Assert.False(recoveredMessage.EnableDebugger, "EnableDebugger should default to false when JSON field is absent");
@@ -57,13 +57,13 @@ public void VerifyEnableDebuggerDeserialization_WithFalse()
// Arrange
var serializer = new DataContractJsonSerializer(typeof(AgentJobRequestMessage));
string jsonWithDisabledDebugger = DoubleQuotify("{'EnableDebugger': false}");
-
+
// Act
using var stream = new MemoryStream();
stream.Write(Encoding.UTF8.GetBytes(jsonWithDisabledDebugger));
stream.Position = 0;
var recoveredMessage = serializer.ReadObject(stream) as AgentJobRequestMessage;
-
+
// Assert
Assert.NotNull(recoveredMessage);
Assert.False(recoveredMessage.EnableDebugger, "EnableDebugger should be false when JSON contains 'EnableDebugger': false");
@@ -161,6 +161,26 @@ public void VerifyActionsDependenciesDeserialization_DefaultsToEmpty()
Assert.Empty(recoveredMessage.ActionsDependencies);
}
+ [Fact]
+ [Trait("Level", "L0")]
+ [Trait("Category", "Common")]
+ public void VerifyDebuggerWelcomeMessageRoundTrips()
+ {
+ // Arrange
+ var serializer = new DataContractJsonSerializer(typeof(AgentJobRequestMessage));
+ string json = DoubleQuotify("{'DebuggerWelcomeMessage': 'Welcome to debugging!'}");
+
+ // Act
+ using var stream = new MemoryStream();
+ stream.Write(Encoding.UTF8.GetBytes(json));
+ stream.Position = 0;
+ var recoveredMessage = serializer.ReadObject(stream) as AgentJobRequestMessage;
+
+ // Assert
+ Assert.NotNull(recoveredMessage);
+ Assert.Equal("Welcome to debugging!", recoveredMessage.DebuggerWelcomeMessage);
+ }
+
private static string DoubleQuotify(string text)
{
return text.Replace('\'', '"');
diff --git a/src/Test/L0/Worker/DapDebuggerL0.cs b/src/Test/L0/Worker/DapDebuggerL0.cs
index f1a29306ff1..92efbaa00c9 100644
--- a/src/Test/L0/Worker/DapDebuggerL0.cs
+++ b/src/Test/L0/Worker/DapDebuggerL0.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
using System.IO;
using System.Net;
using System.Net.Sockets;
@@ -236,7 +236,7 @@ private static async Task ReadWebSocketDataUntilAsync(WebSocket client,
}
}
- private static Mock CreateJobContextWithTunnel(CancellationToken cancellationToken, ushort port, string jobName = null)
+ private static Mock CreateJobContextWithTunnel(CancellationToken cancellationToken, ushort port, string jobName = null, bool overrideWelcomeMessage = false, string welcomeMessage = null)
{
var tunnel = new GitHub.DistributedTask.Pipelines.DebuggerTunnelInfo
{
@@ -245,7 +245,7 @@ private static Mock CreateJobContextWithTunnel(CancellationTo
HostToken = "test-token",
Port = port
};
- var debuggerConfig = new DebuggerConfig(true, tunnel);
+ var debuggerConfig = new DebuggerConfig(true, tunnel, overrideWelcomeMessage, welcomeMessage);
var jobContext = new Mock();
jobContext.Setup(x => x.CancellationToken).Returns(cancellationToken);
jobContext.Setup(x => x.Global).Returns(new GlobalContext { Debugger = debuggerConfig });
@@ -742,6 +742,8 @@ public async Task OnJobCompletedSendsTerminatedAndExitedEvents()
// Read the configurationDone response
await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ // Read the welcome message output event
+ await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
await waitTask;
// Complete the job — OnJobCompletedAsync pauses when stepping,
@@ -849,6 +851,8 @@ public async Task WaitForCommandAsyncUnblocksOnCancellationDuringWait()
Command = "configurationDone"
});
+ await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ // Read the welcome message output event
await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
await waitTask;
@@ -867,5 +871,224 @@ public async Task WaitForCommandAsyncUnblocksOnCancellationDuringWait()
Assert.Equal(completedTask, finished);
}
}
+
+ [Fact]
+ [Trait("Level", "L0")]
+ [Trait("Category", "Worker")]
+ public async Task WelcomeMessageSendsDefaultHelpWhenOverrideDisabled()
+ {
+ using (CreateTestContext())
+ {
+ var port = GetFreePort();
+ using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+ var jobContext = CreateJobContextWithTunnel(cts.Token, port);
+ await _debugger.StartAsync(jobContext.Object);
+
+ using var client = await ConnectClientAsync(port);
+ var stream = client.GetStream();
+
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 1,
+ Type = "request",
+ Command = "configurationDone"
+ });
+
+ // First message: configurationDone response
+ var configDoneResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"configurationDone\"", configDoneResponse);
+
+ // Second message: welcome output event with default help text
+ var welcomeMsg = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"event\":\"output\"", welcomeMsg);
+ Assert.Contains("\"category\":\"console\"", welcomeMsg);
+ Assert.Contains("Actions Debug Console", welcomeMsg);
+ Assert.Contains("help", welcomeMsg);
+
+ await _debugger.StopAsync();
+ }
+ }
+
+ [Fact]
+ [Trait("Level", "L0")]
+ [Trait("Category", "Worker")]
+ public async Task WelcomeMessageShowsCustomMessageWhenOverrideEnabled()
+ {
+ using (CreateTestContext())
+ {
+ var port = GetFreePort();
+ using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+ var jobContext = CreateJobContextWithTunnel(cts.Token, port,
+ overrideWelcomeMessage: true,
+ welcomeMessage: "Welcome to debugging!");
+ await _debugger.StartAsync(jobContext.Object);
+
+ using var client = await ConnectClientAsync(port);
+ var stream = client.GetStream();
+
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 1,
+ Type = "request",
+ Command = "configurationDone"
+ });
+
+ // First: configurationDone response
+ var configDoneResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"configurationDone\"", configDoneResponse);
+
+ // Second: custom welcome message
+ var welcomeMsg = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"event\":\"output\"", welcomeMsg);
+ Assert.Contains("Welcome to debugging!", welcomeMsg);
+
+ await _debugger.StopAsync();
+ }
+ }
+
+ [Fact]
+ [Trait("Level", "L0")]
+ [Trait("Category", "Worker")]
+ public async Task WelcomeMessageSuppressedWhenOverrideEnabledWithEmptyMessage()
+ {
+ using (CreateTestContext())
+ {
+ var port = GetFreePort();
+ using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+ var jobContext = CreateJobContextWithTunnel(cts.Token, port,
+ overrideWelcomeMessage: true,
+ welcomeMessage: "");
+ await _debugger.StartAsync(jobContext.Object);
+
+ using var client = await ConnectClientAsync(port);
+ var stream = client.GetStream();
+
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 1,
+ Type = "request",
+ Command = "configurationDone"
+ });
+
+ // Read configurationDone response
+ var configDoneResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"configurationDone\"", configDoneResponse);
+
+ // Send threads request — if welcome message was suppressed, this
+ // should be the next response (no output event in between)
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 2,
+ Type = "request",
+ Command = "threads"
+ });
+
+ var threadsResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"threads\"", threadsResponse);
+
+ await _debugger.StopAsync();
+ }
+ }
+
+ [Fact]
+ [Trait("Level", "L0")]
+ [Trait("Category", "Worker")]
+ public async Task WelcomeMessageSuppressedWhenOverrideEnabledWithNullMessage()
+ {
+ using (CreateTestContext())
+ {
+ var port = GetFreePort();
+ using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+ var jobContext = CreateJobContextWithTunnel(cts.Token, port,
+ overrideWelcomeMessage: true,
+ welcomeMessage: null);
+ await _debugger.StartAsync(jobContext.Object);
+
+ using var client = await ConnectClientAsync(port);
+ var stream = client.GetStream();
+
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 1,
+ Type = "request",
+ Command = "configurationDone"
+ });
+
+ // Read configurationDone response
+ var configDoneResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"configurationDone\"", configDoneResponse);
+
+ // Send threads request — if welcome message was suppressed, this
+ // should be the next response (no output event in between)
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 2,
+ Type = "request",
+ Command = "threads"
+ });
+
+ var threadsResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"threads\"", threadsResponse);
+
+ await _debugger.StopAsync();
+ }
+ }
+
+ [Fact]
+ [Trait("Level", "L0")]
+ [Trait("Category", "Worker")]
+ public async Task WelcomeMessageSentOnlyOnce()
+ {
+ using (CreateTestContext())
+ {
+ var port = GetFreePort();
+ using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+ var jobContext = CreateJobContextWithTunnel(cts.Token, port);
+ await _debugger.StartAsync(jobContext.Object);
+
+ using var client = await ConnectClientAsync(port);
+ var stream = client.GetStream();
+
+ // First configurationDone
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 1,
+ Type = "request",
+ Command = "configurationDone"
+ });
+
+ var configDoneResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"configurationDone\"", configDoneResponse);
+
+ // Welcome message should appear
+ var welcomeMsg = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"event\":\"output\"", welcomeMsg);
+ Assert.Contains("Actions Debug Console", welcomeMsg);
+
+ // Second configurationDone — should NOT produce another welcome message
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 2,
+ Type = "request",
+ Command = "configurationDone"
+ });
+
+ var secondResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"configurationDone\"", secondResponse);
+
+ // Next message should be threads response, not another welcome output
+ await SendRequestAsync(stream, new Request
+ {
+ Seq = 3,
+ Type = "request",
+ Command = "threads"
+ });
+
+ var threadsResponse = await ReadDapMessageAsync(stream, TimeSpan.FromSeconds(5));
+ Assert.Contains("\"command\":\"threads\"", threadsResponse);
+
+ await _debugger.StopAsync();
+ }
+ }
}
}