feat: capture standard error in server mode session

aws · Feb 3, 2022 · ba361b6 · ba361b6
1 parent 69dd0f9
commit ba361b6
Show file tree

Hide file tree

Showing 5 changed files with 170 additions and 18 deletions.
diff --git a/src/AWS.Deploy.ServerMode.Client/CommandLineWrapper.cs b/src/AWS.Deploy.ServerMode.Client/CommandLineWrapper.cs
@@ -6,7 +6,9 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Runtime.InteropServices;
+using System.Text;
 using System.Threading.Tasks;
+using AWS.Deploy.ServerMode.Client.Utilities;
 
 namespace AWS.Deploy.ServerMode.Client
 {
@@ -19,16 +21,21 @@ public CommandLineWrapper(bool diagnosticLoggingEnabled)
             _diagnosticLoggingEnabled = diagnosticLoggingEnabled;
         }
 
-        public virtual async Task<int> Run(string command, params string[] stdIn)
+        public virtual async Task<RunResult> Run(string command, params string[] stdIn)
         {
             var arguments = RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? $"/c {command}" : $"-c \"{command}\"";
 
+            var strOutput = new CappedStringBuilder(100);
+            var strError = new CappedStringBuilder(50);
+
             var processStartInfo = new ProcessStartInfo
             {
                 FileName = GetSystemShell(),
                 Arguments = arguments,
                 UseShellExecute = false, // UseShellExecute must be false in allow redirection of StdIn.
                 RedirectStandardInput = true,
+                RedirectStandardOutput = true,
+                RedirectStandardError = true,
                 CreateNoWindow = !_diagnosticLoggingEnabled, // It allows displaying stdout and stderr on the screen.
             };
 
@@ -43,9 +50,28 @@ public virtual async Task<int> Run(string command, params string[] stdIn)
                 await process.StandardInput.WriteLineAsync(line).ConfigureAwait(false);
             }
 
+            process.OutputDataReceived += (sender, e) =>
+            {
+                strOutput.AppendLine(e.Data);
+            };
+
+            process.ErrorDataReceived += (sender, e) =>
+            {
+                strError.AppendLine(e.Data);
+            };
+            process.BeginOutputReadLine();
+            process.BeginErrorReadLine();
+
             process.WaitForExit(-1);
 
-            return await Task.FromResult(process.ExitCode).ConfigureAwait(false);
+            var result = new RunResult
+            {
+                ExitCode = process.ExitCode,
+                StandardError = strError.ToString(),
+                StandardOut = strOutput.GetLastLines(5),
+            };
+
+            return await Task.FromResult(result).ConfigureAwait(false);
         }
 
         private string GetSystemShell()
@@ -70,4 +96,28 @@ private bool TryGetEnvironmentVariable(string variable, out string? value)
             return !string.IsNullOrEmpty(value);
         }
     }
+
+    public class RunResult
+    {
+        /// <summary>
+        /// Indicates if this command was run successfully.  This checks that
+        /// <see cref="StandardError"/> is empty.
+        /// </summary>
+        public bool Success => string.IsNullOrWhiteSpace(StandardError);
+
+        /// <summary>
+        /// Fully read <see cref="Process.StandardOutput"/>
+        /// </summary>
+        public string StandardOut { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Fully read <see cref="Process.StandardError"/>
+        /// </summary>
+        public string StandardError { get; set; } = string.Empty;
+
+        /// <summary>
+        /// Fully read <see cref="Process.ExitCode"/>
+        /// </summary>
+        public int ExitCode { get; set; }
+    }
 }
diff --git a/src/AWS.Deploy.ServerMode.Client/ServerModeSession.cs b/src/AWS.Deploy.ServerMode.Client/ServerModeSession.cs
@@ -164,9 +164,12 @@ public async Task Start(CancellationToken cancellationToken)
 
                 // For -100 errors, we want to check all the ports in the configured port range
                 // If the error code other than -100, this is an unexpected exit code.
-                if (startServerTask.Result != TCP_PORT_ERROR)
+                if (startServerTask.Result.ExitCode != TCP_PORT_ERROR)
                 {
-                    throw new InternalServerModeException($"\"{command}\" failed for unknown reason.");
+                    throw new InternalServerModeException(
+                        string.IsNullOrEmpty(startServerTask.Result.StandardError) ?
+                        $"\"{command}\" failed for unknown reason." :
+                        startServerTask.Result.StandardError);
                 }
             }
 

diff --git a/src/AWS.Deploy.ServerMode.Client/Utilities/CappedStringBuilder.cs b/src/AWS.Deploy.ServerMode.Client/Utilities/CappedStringBuilder.cs
@@ -0,0 +1,48 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace AWS.Deploy.ServerMode.Client.Utilities
+{
+    public class CappedStringBuilder
+    {
+        public int LineLimit { get; }
+        public int LineCount {
+            get
+            {
+                return _lines?.Count ?? 0;
+            }
+        }
+
+        private readonly Queue<string> _lines;
+
+        public CappedStringBuilder(int lineLimit)
+        {
+            _lines = new Queue<string>(lineLimit);
+            LineLimit = lineLimit;
+        }
+
+        public void AppendLine(string value)
+        {
+            if (LineCount >= LineLimit)
+            {
+                _lines.Dequeue();
+            }
+
+            _lines.Enqueue(value);
+        }
+
+        public string GetLastLines(int lineCount)
+        {
+            return _lines.Reverse().Take(lineCount).Reverse().Aggregate((x, y) => x + Environment.NewLine + y);
+        }
+
+        public override string ToString()
+        {
+            return _lines.Aggregate((x, y) => x + Environment.NewLine + y);
+        }
+    }
+}
diff --git a/test/AWS.Deploy.ServerMode.Client.UnitTests/CappedStringBuilderTests.cs b/test/AWS.Deploy.ServerMode.Client.UnitTests/CappedStringBuilderTests.cs
@@ -0,0 +1,41 @@
+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+using System;
+using AWS.Deploy.ServerMode.Client.Utilities;
+using Xunit;
+
+namespace AWS.Deploy.ServerMode.Client.UnitTests
+{
+    public class CappedStringBuilderTests
+    {
+        private readonly CappedStringBuilder _cappedStringBuilder;
+
+        public CappedStringBuilderTests()
+        {
+            _cappedStringBuilder = new CappedStringBuilder(5);
+        }
+
+        [Fact]
+        public void AppendLineTest()
+        {
+            _cappedStringBuilder.AppendLine("test1");
+            _cappedStringBuilder.AppendLine("test2");
+            _cappedStringBuilder.AppendLine("test3");
+
+            Assert.Equal(3, _cappedStringBuilder.LineCount);
+            Assert.Equal($"test1{Environment.NewLine}test2{Environment.NewLine}test3", _cappedStringBuilder.ToString());
+        }
+
+        [Fact]
+        public void GetLastLinesTest()
+        {
+            _cappedStringBuilder.AppendLine("test1");
+            _cappedStringBuilder.AppendLine("test2");
+
+            Assert.Equal(2, _cappedStringBuilder.LineCount);
+            Assert.Equal("test2", _cappedStringBuilder.GetLastLines(1));
+            Assert.Equal($"test1{Environment.NewLine}test2", _cappedStringBuilder.GetLastLines(2));
+        }
+    }
+}
diff --git a/test/AWS.Deploy.ServerMode.Client.UnitTests/ServerModeSessionTests.cs b/test/AWS.Deploy.ServerMode.Client.UnitTests/ServerModeSessionTests.cs
@@ -27,7 +27,8 @@ public ServerModeSessionTests()
         public async Task Start()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.OK);
 
             // Act
@@ -44,7 +45,8 @@ public async Task Start()
         public async Task Start_PortUnavailable()
         {
             // Arrange
-            MockCommandLineWrapperRun(-100);
+            var runResult = new RunResult { ExitCode = -100 };
+            MockCommandLineWrapperRun(runResult);
             MockHttpGet(HttpStatusCode.NotFound, TimeSpan.FromSeconds(5));
 
             // Act & Assert
@@ -58,7 +60,8 @@ await Assert.ThrowsAsync<PortUnavailableException>(async () =>
         public async Task Start_HttpGetThrows()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGetThrows();
 
             // Act & Assert
@@ -72,7 +75,8 @@ await Assert.ThrowsAsync<InternalServerModeException>(async () =>
         public async Task Start_HttpGetForbidden()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.Forbidden);
 
             // Act & Assert
@@ -96,7 +100,8 @@ public async Task IsAlive_BaseUrlNotInitialized()
         public async Task IsAlive_GetAsyncThrows()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.OK);
             await _serverModeSession.Start(CancellationToken.None);
 
@@ -113,7 +118,8 @@ public async Task IsAlive_GetAsyncThrows()
         public async Task IsAlive_HttpResponseSuccess()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.OK);
             await _serverModeSession.Start(CancellationToken.None);
 
@@ -128,7 +134,8 @@ public async Task IsAlive_HttpResponseSuccess()
         public async Task IsAlive_HttpResponseFailure()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.OK);
             await _serverModeSession.Start(CancellationToken.None);
 
@@ -145,7 +152,8 @@ public async Task IsAlive_HttpResponseFailure()
         public async Task TryGetRestAPIClient()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.OK);
             await _serverModeSession.Start(CancellationToken.None);
 
@@ -161,7 +169,8 @@ public async Task TryGetRestAPIClient()
         public void TryGetRestAPIClient_WithoutStart()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.OK);
 
             // Act
@@ -176,7 +185,8 @@ public void TryGetRestAPIClient_WithoutStart()
         public async Task TryGetDeploymentCommunicationClient()
         {
             // Arrange
-            MockCommandLineWrapperRun(0, TimeSpan.FromSeconds(100));
+            var runResult = new RunResult { ExitCode = 0 };
+            MockCommandLineWrapperRun(runResult, TimeSpan.FromSeconds(100));
             MockHttpGet(HttpStatusCode.OK);
             await _serverModeSession.Start(CancellationToken.None);
 
@@ -228,15 +238,15 @@ private void MockHttpGetThrows() =>
                     ItExpr.IsAny<CancellationToken>())
                 .Throws(new Exception());
 
-        private void MockCommandLineWrapperRun(int statusCode) =>
+        private void MockCommandLineWrapperRun(RunResult runResult) =>
             _commandLineWrapper
                 .Setup(wrapper => wrapper.Run(It.IsAny<string>(), It.IsAny<string[]>()))
-                .ReturnsAsync(statusCode);
+                .ReturnsAsync(runResult);
 
-        private void MockCommandLineWrapperRun(int statusCode, TimeSpan delay) =>
+        private void MockCommandLineWrapperRun(RunResult runResult, TimeSpan delay) =>
             _commandLineWrapper
                 .Setup(wrapper => wrapper.Run(It.IsAny<string>(), It.IsAny<string[]>()))
-                .ReturnsAsync(statusCode, delay);
+                .ReturnsAsync(runResult, delay);
 
         private Task<AWSCredentials> CredentialGenerator() => throw new NotImplementedException();
     }