Add an API to return available versions of Node and NPM

Fixes #784

Kudu.Contracts/Diagnostics/RuntimeInfo.cs

@@ -0,0 +1,12 @@
+using System.Collections.Generic;
+using System.Runtime.Serialization;
+
+namespace Kudu.Services.Diagnostics
+{
+    [DataContract(Name = "runtime")]
+    public class RuntimeInfo
+    {
+        [DataMember(Name = "nodejs")]
+        public IEnumerable<Dictionary<string, string>> NodeVerions { get; set; }
+    }
+}

Kudu.Contracts/Kudu.Contracts.csproj

@@ -46,6 +46,7 @@
     <Compile Include="Deployment\LogEntryType.cs" />
     <Compile Include="Diagnostics\ProcessInfo.cs" />
     <Compile Include="Diagnostics\ProcessThreadInfo.cs" />
+    <Compile Include="Diagnostics\RuntimeInfo.cs" />
     <Compile Include="Editor\VfsStatEntry.cs" />
     <Compile Include="Hooks\ConflictException.cs" />
     <Compile Include="Hooks\WebHook.cs" />

Kudu.Services.Test/Kudu.Services.Test.csproj

@@ -70,6 +70,7 @@
     <Compile Include="KilnHgHandlerFacts.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="ReceivePackHandlerFacts.cs" />
+    <Compile Include="RuntimeControllerFacts.cs" />
     <Compile Include="SettingsControllerFacts.cs" />
     <Compile Include="SSHKeyControllerTests.cs" />
     <Compile Include="TestMessageHandler.cs" />

Kudu.Services.Test/RuntimeControllerFacts.cs

@@ -0,0 +1,83 @@
+using System;
+using System.IO;
+using System.IO.Abstractions;
+using System.Linq;
+using System.Text;
+using Kudu.Contracts.Tracing;
+using Kudu.Services.Diagnostics;
+using Moq;
+using Xunit;
+
+namespace Kudu.Services.Test
+{
+    public class RuntimeControllerFacts
+    {
+        private static readonly string _programFilesDir = Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86);
+        private static readonly string _nodeDir = Path.Combine(_programFilesDir, "nodejs");
+
+        [Fact]
+        public void RuntimeControllerReturnsEmptyListIfDirectoryDoesNotExist()
+        {
+            // Arrange
+            var nodeDir = new Mock<DirectoryInfoBase>();
+            nodeDir.Setup(d => d.Exists).Returns(false);
+            var directory = new Mock<IDirectoryInfoFactory>();
+            directory.Setup(d => d.FromDirectoryName(_nodeDir)).Returns(nodeDir.Object);
+            var fileSystem = new Mock<IFileSystem>();
+            fileSystem.Setup(f => f.DirectoryInfo).Returns(directory.Object);
+
+            var controller = new RuntimeController(Mock.Of<ITracer>(), fileSystem.Object);
+
+            // Act
+            var runtimeInfo = controller.GetRuntimeVersions();
+
+            // Assert
+            Assert.Empty(runtimeInfo.NodeVerions);
+        }
+
+        [Fact]
+        public void RuntimeControllerReturnsNodeVersions()
+        {
+            // Arrange
+            var nodeDir = new Mock<DirectoryInfoBase>();
+            nodeDir.Setup(d => d.Exists).Returns(true);
+            nodeDir.Setup(d => d.GetDirectories()).Returns(new[] { 
+                CreateDirectory("0.8.19", CreateFile("npm.txt", "1.2.8")), 
+                CreateDirectory("0.10.5", CreateFile("npm.txt", "1.3.11")), 
+                CreateDirectory("0.10.18"), 
+                CreateDirectory("node_modules"), 
+                CreateDirectory("docs") 
+            });
+            var directoryInfo = new Mock<IDirectoryInfoFactory>();
+            directoryInfo.Setup(d => d.FromDirectoryName(_nodeDir)).Returns(nodeDir.Object);
+            var fileSystem = new Mock<IFileSystem>();
+            fileSystem.Setup(f => f.DirectoryInfo).Returns(directoryInfo.Object);
+
+            var controller = new RuntimeController(Mock.Of<ITracer>(), fileSystem.Object);
+
+            // Act
+            var nodeVersions = controller.GetRuntimeVersions().NodeVerions.ToList();
+
+            // Assert
+            Assert.Equal(new[] { "0.8.19", "0.10.5", "0.10.18" }, nodeVersions.Select(v => v["version"]));
+            Assert.Equal(new[] { "1.2.8", "1.3.11", null }, nodeVersions.Select(v => v["npm"]));
+        }
+
+        private DirectoryInfoBase CreateDirectory(string name, params FileInfoBase[] files)
+        {
+            var dir = new Mock<DirectoryInfoBase>();
+            dir.SetupGet(d => d.Name).Returns(name);
+            dir.Setup(d => d.GetFiles(It.IsAny<string>())).Returns(files);
+            return dir.Object;
+        }
+
+        private FileInfoBase CreateFile(string fileName, string content)
+        {
+            var file = new Mock<FileInfoBase>();
+            file.SetupGet(f => f.Name).Returns(fileName);
+            var memoryStream = new MemoryStream(Encoding.UTF8.GetBytes(content));
+            file.Setup(f => f.OpenRead()).Returns(memoryStream);
+            return file.Object;
+        }
+    }
+}

Kudu.Services.Web/App_Start/NinjectServices.cs

@@ -338,6 +338,9 @@ public static void RegisterRoutes(IKernel kernel, RouteCollection routes)
             routes.MapHttpRoute("all-threads", "diagnostics/processes/{id}/threads", new { controller = "Process", action = "GetAllThreads" }, new { verb = new HttpMethodConstraint("GET") });
             routes.MapHttpRoute("one-process-thread", "diagnostics/processes/{processId}/threads/{threadId}", new { controller = "Process", action = "GetThread" }, new { verb = new HttpMethodConstraint("GET") });
 
+            // Runtime
+            routes.MapHttpRoute("runtime", "diagnostics/runtime", new { controller = "Runtime", action = "GetRuntimeVersions" }, new { verb = new HttpMethodConstraint("GET") });
+
             // Hooks
             routes.MapHttpRoute("unsubscribe-hook", "hooks/{id}", new { controller = "WebHooks", action = "Unsubscribe" }, new { verb = new HttpMethodConstraint("DELETE") });
             routes.MapHttpRoute("get-hook", "hooks/{id}", new { controller = "WebHooks", action = "GetWebHook" }, new { verb = new HttpMethodConstraint("GET") });

Kudu.Services/Diagnostics/RuntimeController.cs

@@ -0,0 +1,81 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.IO.Abstractions;
+using System.Linq;
+using System.Net.Http.Formatting;
+using System.Text.RegularExpressions;
+using System.Web.Http;
+using System.Web.Http.Controllers;
+using Kudu.Contracts.Tracing;
+using Newtonsoft.Json;
+
+namespace Kudu.Services.Diagnostics
+{
+    public class RuntimeController : ApiController
+    {
+        private const string VersionKey = "version";
+        private static readonly Regex _versionRegex = new Regex(@"^\d+\.\d+", RegexOptions.ExplicitCapture);
+        private readonly ITracer _tracer;
+        private readonly IFileSystem _fileSystem;
+
+        public RuntimeController(ITracer tracer, IFileSystem fileSystem)
+        {
+            _tracer = tracer;
+            _fileSystem = fileSystem;
+        }
+
+        protected override void Initialize(HttpControllerContext controllerContext)
+        {
+            controllerContext.Configuration.Formatters.Clear();
+
+            var settings = new JsonSerializerSettings
+            {
+                ContractResolver = new LowerCasePropertyNamesContractResolver()
+            };
+            controllerContext.Configuration.Formatters.Add(new JsonMediaTypeFormatter { SerializerSettings = settings });
+        }
+
+        [HttpGet]
+        public RuntimeInfo GetRuntimeVersions()
+        {
+            using (_tracer.Step("RuntimeController.GetRuntimeVersions"))
+            {
+                return new RuntimeInfo
+                {
+                    NodeVerions = GetNodeVersions()
+                };
+            }
+        }
+
+        private IEnumerable<Dictionary<string, string>> GetNodeVersions()
+        {
+            string nodeRoot = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ProgramFilesX86), "nodejs");
+            var directoryInfo = _fileSystem.DirectoryInfo.FromDirectoryName(nodeRoot);
+            if (directoryInfo.Exists)
+            {
+                return directoryInfo.GetDirectories()
+                                    .Where(dir => _versionRegex.IsMatch(dir.Name))
+                                    .Select(dir => new Dictionary<string, string>
+                                    {
+                                        { VersionKey, dir.Name },
+                                        { "npm", TryReadNpmVersion(dir) }
+                                    });
+            }
+            return Enumerable.Empty<Dictionary<string, string>>();
+        }
+
+        private string TryReadNpmVersion(DirectoryInfoBase nodeDir)
+        {
+            var npmRedirectionFile = nodeDir.GetFiles("npm.txt").FirstOrDefault();
+            if (npmRedirectionFile == null)
+            {
+                return null;
+            }
+            using (StreamReader reader = new StreamReader(npmRedirectionFile.OpenRead()))
+            {
+                return reader.ReadLine();
+            }
+        }
+    }
+}

Kudu.Services/Infrastructure/LowerCasePropertyNamesContractResolver.cs

@@ -0,0 +1,12 @@
+using Newtonsoft.Json.Serialization;
+
+namespace Kudu.Services
+{
+    public class LowerCasePropertyNamesContractResolver : DefaultContractResolver
+    {
+        protected override string ResolvePropertyName(string propertyName)
+        {
+            return propertyName.ToLowerInvariant();
+        }
+    }
+}

Kudu.Services/Kudu.Services.csproj

@@ -98,6 +98,7 @@
     <Compile Include="Diagnostics\LogStreamHandler.cs" />
     <Compile Include="Diagnostics\LogStreamManager.cs" />
     <Compile Include="Diagnostics\ProcessController.cs" />
+    <Compile Include="Diagnostics\RuntimeController.cs" />
     <Compile Include="Editor\VfsController.cs" />
     <Compile Include="FetchHelpers\DropboxEntryInfo.cs" />
     <Compile Include="FetchHelpers\DropboxDeployInfo.cs" />
@@ -108,6 +109,7 @@
     <Compile Include="Hooks\WebHooksController.cs" />
     <Compile Include="HttpRequestExtensions.cs" />
     <Compile Include="Infrastructure\InstanceIdUtility.cs" />
+    <Compile Include="Infrastructure\LowerCasePropertyNamesContractResolver.cs" />
     <Compile Include="ServiceHookHandlers\CodebaseHqHandler.cs" />
     <Compile Include="ServiceHookHandlers\CodePlexHandler.cs" />
     <Compile Include="ServiceHookHandlers\DropboxHandler.cs" />