- Starting implementing a file based topology descriptor cache.

- Adding FileExists to AppDataFolder.
- Unit tests.

--HG--
branch : dev

src/Orchard.Tests/Environment/Configuration/AppDataFolderTests.cs

@@ -1,8 +1,5 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
+using System.IO;
 using System.Linq;
-using System.Text;
 using NUnit.Framework;
 using Orchard.Environment.Configuration;
 
@@ -91,5 +88,16 @@ this is
 a
 test"));
         }
+
+        [Test]
+        public void FileExistsReturnsFalseForNonExistingFile() {
+            Assert.That(_appDataFolder.FileExists("notexisting"), Is.False);
+        }
+
+        [Test]
+        public void FileExistsReturnsTrueForExistingFile() {
+            _appDataFolder.CreateFile("alpha\\foo\\bar.txt", "");
+            Assert.That(_appDataFolder.FileExists("alpha\\foo\\bar.txt"), Is.True);
+        }
     }
 }

src/Orchard.Tests/Environment/Topology/DefaultTopologyDescriptorCacheTests.cs

@@ -11,14 +11,27 @@ namespace Orchard.Tests.Environment.Topology {
     [TestFixture]
     public class DefaultTopologyDescriptorCacheTests {
         private IContainer _container;
+        private string _tempFolder;
+        private IAppDataFolder _appDataFolder;
 
         [SetUp]
         public void Init() {
+            _tempFolder = Path.GetTempFileName();
+            File.Delete(_tempFolder);
+            Directory.CreateDirectory(_tempFolder);
+            _appDataFolder = new AppDataFolder();
+            _appDataFolder.SetBasePath(_tempFolder);
             var builder = new ContainerBuilder();
+            builder.RegisterInstance(_appDataFolder).As<IAppDataFolder>();
             builder.RegisterType<DefaultTopologyDescriptorCache>().As<ITopologyDescriptorCache>();
             _container = builder.Build();
         }
 
+        [TearDown]
+        public void Term() {
+            Directory.Delete(_tempFolder, true);
+        }
+
         [Test]
         public void FetchReturnsNullForCacheMiss() {
             var service = _container.Resolve<ITopologyDescriptorCache>();

src/Orchard/Environment/Configuration/AppDataFolder.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Web.Hosting;
@@ -16,6 +17,7 @@ namespace Orchard.Environment.Configuration {
         void CreateFile(string path, string content);
         string ReadFile(string path);
         void DeleteFile(string path);
+        bool FileExists(string path);
 
         string CreateDirectory(string path);
 
@@ -51,6 +53,11 @@ namespace Orchard.Environment.Configuration {
             File.Delete(Path.Combine(_basePath, path));
         }
 
+        public bool FileExists(string path) {
+            var filePath = Path.Combine(_basePath, path);
+            return File.Exists(filePath);
+        }
+
         public IEnumerable<string> ListFiles(string path) {
             var directoryPath = Path.Combine(_basePath, path);
             if (!Directory.Exists(directoryPath))

src/Orchard/Environment/Topology/DefaultTopologyDescriptorCache.cs

@@ -1,17 +1,45 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
+using Orchard.Environment.Configuration;
 using Orchard.Environment.Topology.Models;
+using Orchard.Localization;
+using Orchard.Logging;
 
 namespace Orchard.Environment.Topology {
     public class DefaultTopologyDescriptorCache : ITopologyDescriptorCache {
         readonly IDictionary<string, ShellTopologyDescriptor> _cache= new Dictionary<string, ShellTopologyDescriptor>();
+        private readonly IAppDataFolder _appDataFolder;
+        private const string TopologyCacheFileName = "cache.dat";
+
+        public DefaultTopologyDescriptorCache(IAppDataFolder appDataFolder) {
+            _appDataFolder = appDataFolder;
+            T = NullLocalizer.Instance;
+            Logger = NullLogger.Instance;
+
+        }
+
+        public ILogger Logger { get; set; }
+        private Localizer T { get; set; }
+
+        #region Implementation of ITopologyDescriptorCache
 
         public ShellTopologyDescriptor Fetch(string name) {
+            VerifyCacheFile();
             ShellTopologyDescriptor value;
             return _cache.TryGetValue(name, out value) ? value : null;
         }
 
         public void Store(string name, ShellTopologyDescriptor descriptor) {
+            VerifyCacheFile();
             _cache[name] = descriptor;
         }
+
+        #endregion
+
+        private void VerifyCacheFile() {
+            if (!_appDataFolder.FileExists(TopologyCacheFileName)) {
+                _appDataFolder.CreateFile(TopologyCacheFileName, String.Empty);
+            }
+        }
     }
 }