SLVS-1434 Extend JsonFileHandler (#5661)

[SLVS-1434](https://sonarsource.atlassian.net/browse/SLVS-1434)

[SLVS-1434]:
https://sonarsource.atlassian.net/browse/SLVS-1434?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

src/Core.UnitTests/Binding/ServerConnectionTests.cs

@@ -57,6 +57,7 @@ public void Ctor_SonarCloud_NullCredentials_SetsNull()
     [TestMethod]
     public void Ctor_SonarCloud_SetsProperties()
     {
+        var expectedServerUri = new Uri("https://sonarcloud.io");
         var serverConnectionSettings = new ServerConnectionSettings(false);
         var credentials = Substitute.For<ICredentials>();
         var sonarCloud = new ServerConnection.SonarCloud(Org, serverConnectionSettings, credentials);

src/Core.UnitTests/Persistence/JsonFileHandlerTest.cs

@@ -55,76 +55,29 @@ public void MefCtor_CheckExports()
     [TestMethod]
     public void Mef_CheckIsSingleton()
     {
-        MefTestHelpers.CheckIsSingletonMefComponent<JsonFileHandler>();
+        MefTestHelpers.CheckIsNonSharedMefComponent<JsonFileHandler>();
     }
 
     [TestMethod]
-    public void TryReadFile_FileDoesNotExist_ReturnsFalse()
-    {
-        fileSystem.File.Exists(FilePath).Returns(false);
-
-        var succeeded = testSubject.TryReadFile(FilePath, out TestType deserializedContent);
-
-        succeeded.Should().BeFalse();
-        deserializedContent.Should().BeNull();
-        fileSystem.File.Received(1).Exists(FilePath);
-    }
-
-    [TestMethod]
-    public void TryReadFile_FileExists_ReturnsTrueAndDeserializeContent()
-    {
-        var expectedContent = new TestType("test");
-        var serializedContent = JsonConvert.SerializeObject(expectedContent);
-        fileSystem.File.Exists(FilePath).Returns(true);
-        fileSystem.File.ReadAllText(FilePath).Returns(serializedContent);
-        serializer.TryDeserialize(Arg.Any<string>(), out Arg.Any<TestType>()).Returns(true);
-
-        var succeeded = testSubject.TryReadFile(FilePath, out TestType _);
-
-        succeeded.Should().BeTrue();
-        Received.InOrder(() =>
-        {
-            fileSystem.File.Exists(FilePath);
-            fileSystem.File.ReadAllText(FilePath);
-            serializer.TryDeserialize(Arg.Any<string>(), out Arg.Any<TestType>());
-        });
-    }
-
-    [TestMethod]
-    public void TryReadFile_ReadingFileThrowsException_WritesLogAndReturnsFalse()
+    public void ReadFile_ReadingFileThrowsException_TrowsException()
     {
         var exceptionMsg = "IO failed";
-        fileSystem.File.Exists(FilePath).Returns(true);
         fileSystem.File.When(x => x.ReadAllText(FilePath)).Do(x => throw new Exception(exceptionMsg));
 
-        var succeeded = testSubject.TryReadFile(FilePath, out TestType _);
-
-        succeeded.Should().BeFalse();
-        logger.Received(1).WriteLine(exceptionMsg);
-    }
-
-    [TestMethod]
-    public void TryReadFile_DeserializationThrowsException_WritesLogAndReturnsFalse()
-    {
-        var exceptionMsg = "deserialization failed";
-        fileSystem.File.Exists(FilePath).Returns(true);
-        serializer.When(x => x.TryDeserialize(Arg.Any<string>(), out Arg.Any<TestType>())).Do(x => throw new Exception(exceptionMsg));
+        Action act  = () => testSubject.ReadFile<TestType>(FilePath);
 
-        var succeeded = testSubject.TryReadFile(FilePath, out TestType _);
-
-        succeeded.Should().BeFalse();
-        logger.Received(1).WriteLine(exceptionMsg);
+        act.Should().Throw<Exception>().WithMessage(exceptionMsg);
     }
 
     [TestMethod]
-    public void TryReadFile_DeserializationFails_WritesLogAndReturnsFalse()
+    public void ReadFile_DeserializationThrowsException_TrowsException()
     {
-        fileSystem.File.Exists(FilePath).Returns(true);
-        serializer.TryDeserialize(Arg.Any<string>(), out Arg.Any<TestType>()).Returns(false);
+        var exceptionMsg = "IO failed";
+        serializer.When(x => x.Deserialize<TestType>(Arg.Any<string>())).Do(x => throw new Exception(exceptionMsg));
 
-        var succeeded = testSubject.TryReadFile(FilePath, out TestType _);
+        Action act = () => testSubject.ReadFile<TestType>(FilePath);
 
-        succeeded.Should().BeFalse();
+        act.Should().Throw<Exception>().WithMessage(exceptionMsg);
     }
 
     [TestMethod]

src/Core.UnitTests/Persistence/JsonSerializerTests.cs

@@ -96,4 +96,24 @@ public void TryDeserialize_Fails_LogsAndReturnsFalse()
         deserializedObj.Should().BeNull();
         logger.Received(1).WriteLine(string.Format(PersistenceStrings.FailedToDeserializeObject, nameof(TestType)));
     }
+
+    [TestMethod]
+    public void Deserialize_Succeeds_ReturnsString()
+    {
+        var serializedString = "{\"PropName\":\"abc\"}";
+
+        var deserializedObj = testSubject.Deserialize<TestType>(serializedString);
+
+        deserializedObj.Should().BeEquivalentTo(new TestType("abc"));
+    }
+
+    [TestMethod]
+    public void Deserialize_Fails_ThrowsException()
+    {
+        var serializedString = "invalid";
+
+        Action act = () => testSubject.Deserialize<TestType>(serializedString);
+
+        act.Should().Throw<Exception>();
+    }
 }

src/Core/Persistence/JsonFileHandler.cs

@@ -27,18 +27,32 @@ namespace SonarLint.VisualStudio.Core.Persistence;
 
 public interface IJsonFileHandler
 {
-    bool TryReadFile<T>(string filePath, out T content) where T : class;
+    /// <summary>
+    /// Reads the json file and deserializes its content to the provided type.
+    /// </summary>
+    /// <typeparam name="T">The type of the model that will be serialized</typeparam>
+    /// <param name="filePath">The path to the file</param>
+    /// <returns>Returns the content of the json file deserialized to the provided type.</returns>
+    T ReadFile<T>(string filePath) where T : class;
+
+    /// <summary>
+    /// Tries to deserialize the model and write it to the json file.
+    /// If the file does not exist, it will be created.
+    /// </summary>
+    /// <typeparam name="T">The type of the model that will be deserialized</typeparam>
+    /// <param name="filePath">The path to the file</param>
+    /// <param name="model">The model that will be deserialized</param>
+    /// <returns>True if the model was deserialized successfully and written to the file. False otherwise</returns>
     bool TryWriteToFile<T>(string filePath, T model) where T : class;
 }
 
 [Export(typeof(IJsonFileHandler))]
-[PartCreationPolicy(CreationPolicy.Shared)]
+[PartCreationPolicy(CreationPolicy.NonShared)]
 public class JsonFileHandler : IJsonFileHandler
 {
     private readonly ILogger logger;
     private readonly IFileSystem fileSystem;
     private readonly IJsonSerializer jsonSerializer;
-    private static readonly object Locker = new();
 
     [ImportingConstructor]
     public JsonFileHandler(IJsonSerializer jsonSerializer, ILogger logger) : this(new FileSystem(), jsonSerializer, logger) { }
@@ -50,52 +64,34 @@ public JsonFileHandler(IJsonSerializer jsonSerializer, ILogger logger) : this(ne
         this.logger = logger;
     }
 
-    public bool TryReadFile<T>(string filePath, out T content) where T: class
+    public T ReadFile<T>(string filePath) where T : class
     {
-        content = null;
-        if (!fileSystem.File.Exists(filePath))
-        {
-            return false;
-        }
-
-        try
-        {
-            var jsonContent = fileSystem.File.ReadAllText(filePath);
-            return jsonSerializer.TryDeserialize(jsonContent, out content);
-
-        }
-        catch (Exception ex) when (!ErrorHandler.IsCriticalException(ex))
-        {
-            logger.WriteLine(ex.Message);
-            return false;
-        }
+        var jsonContent = fileSystem.File.ReadAllText(filePath);
+        return jsonSerializer.Deserialize<T>(jsonContent);
     }
 
     public bool TryWriteToFile<T>(string filePath, T model) where T : class
     {
-        lock (Locker)
+        try
         {
-            try
+            var directoryName = Path.GetDirectoryName(filePath);
+            if (!fileSystem.Directory.Exists(directoryName))
             {
-                var directoryName = Path.GetDirectoryName(filePath);
-                if (!fileSystem.Directory.Exists(directoryName))
-                {
-                    fileSystem.Directory.CreateDirectory(directoryName);
-                }
-
-                var wasContentDeserialized = jsonSerializer.TrySerialize(model, out string serializedObj, Formatting.Indented);
-                if (wasContentDeserialized)
-                {
-                    fileSystem.File.WriteAllText(filePath, serializedObj);
-                    return true;
-                }
+                fileSystem.Directory.CreateDirectory(directoryName);
             }
-            catch (Exception ex) when (!ErrorHandler.IsCriticalException(ex))
+
+            var wasContentDeserialized = jsonSerializer.TrySerialize(model, out string serializedObj, Formatting.Indented);
+            if (wasContentDeserialized)
             {
-                logger.WriteLine(ex.Message);
+                fileSystem.File.WriteAllText(filePath, serializedObj);
+                return true;
             }
-
-            return false;
         }
+        catch (Exception ex) when (!ErrorHandler.IsCriticalException(ex))
+        {
+            logger.WriteLine(ex.Message);
+        }
+
+        return false;
     }
 }

src/Core/Persistence/JsonSerializer.cs

@@ -27,6 +27,7 @@ namespace SonarLint.VisualStudio.Core.Persistence;
 public interface IJsonSerializer
 {
     bool TryDeserialize<T>(string json, out T deserializedObj, JsonSerializerSettings serializerSettings = null) where T : class;
+    T Deserialize<T>(string json, JsonSerializerSettings serializerSettings = null) where T : class;
     bool TrySerialize<T>(T objectToSerialize, out string serializedObj, Formatting formatting = Formatting.None,
         JsonSerializerSettings serializerSettings = null) where T : class;
 }
@@ -55,7 +56,7 @@ public bool TryDeserialize<T>(string json, out T deserializedObj, JsonSerializer
         deserializedObj = null;
         try
         {
-            deserializedObj = JsonConvert.DeserializeObject<T>(json, serializerSettings);
+            deserializedObj = Deserialize<T>(json, serializerSettings);
             return true;
         }
         catch (Exception)
@@ -65,6 +66,11 @@ public bool TryDeserialize<T>(string json, out T deserializedObj, JsonSerializer
         }
     }
 
+    public T Deserialize<T>(string json, JsonSerializerSettings serializerSettings = null) where T : class
+    {
+       return JsonConvert.DeserializeObject<T>(json, serializerSettings);
+    }
+
     public bool TrySerialize<T>(T objectToSerialize, out string serializedObj, Formatting formatting = Formatting.None, JsonSerializerSettings serializerSettings = null) where T: class
     {
         serializedObj = null;