feature(#59): Added TempFileStream

docs/Common/README.md

@@ -3,7 +3,6 @@
 - [Common](#common)
   - [PropertyUtil](#propertyutil)
   - [PathUtil](#pathutil)
-  - [Transactions](#transactions)
 
 This project contains general, framework independent utilities and abstractions.
 
@@ -33,10 +32,15 @@ Utility for paths. Does not try to replicate `System.IO.Path`, but adds some hel
 
 Currently this only has methods for removing invalid chars from paths and filenames, as `Path.GetInvalidFileNameChars()` returns different values based on the OS, while `PathUtil` uses a fixed set. This may be for example required when generating a filename for a download.
 
-## Transactions
+## TempFileStream
 
-If you need to use trasactions, use the transaction scope handler to run your code in one. You normally don't need to care about transactions, as the MediatR-Pipeline and Hangfire-Jobs have handlers for that (`TransactionalDecorator`, `TransactionalJobHandler`). See the [Hangfire](../Hangfire/README.md) or [MediatR](#mediatr) docs for details.
+This creates a temporary file that gets automatically deleted when it is closed. Example:
 
 ```cs
-Container.RegisterSingleton<ITransactionScopeHandler, TransactionScopeHandler>();
-```
+await using (var fs = new TempFileStream())
+{
+    // Write content to file
+    // Upload file
+}
+// File was deleted at this point.
+```

src/Common/src/IO/TempFileStream.cs

@@ -0,0 +1,15 @@
+// Copyright (c) Fusonic GmbH. All rights reserved.
+// Licensed under the MIT License. See LICENSE file in the project root for license information.
+
+namespace Fusonic.Extensions.Common.IO;
+
+/// <summary>
+/// A file stream which points to a temporary file. The file automatically gets deleted when the stream is closed.
+/// </summary>
+public class TempFileStream(int bufferSize = 4096) : FileStream(
+    Path.GetTempFileName(),
+    FileMode.Create,
+    FileAccess.ReadWrite,
+    FileShare.Read,
+    bufferSize,
+    FileOptions.DeleteOnClose);

src/Common/test/IO/TempFileStreamTests.cs

@@ -0,0 +1,47 @@
+// Copyright (c) Fusonic GmbH. All rights reserved.
+// Licensed under the MIT License. See LICENSE file in the project root for license information.
+
+using System.Text;
+using FluentAssertions;
+using Fusonic.Extensions.Common.IO;
+using Xunit;
+
+namespace Fusonic.Extensions.Common.Tests.IO;
+
+public class TempFileStreamTests
+{
+    [Fact]
+    public async Task TempFileStream_CreatesFile()
+    {
+        await using var stream = new TempFileStream();
+        File.Exists(stream.Name).Should().BeTrue();
+    }
+
+    [Fact]
+    public async Task TempFileStream_CanWriteToFile()
+    {
+        await using var stream = new TempFileStream();
+        await stream.WriteAsync("Test"u8.ToArray());
+        await stream.FlushAsync();
+
+        stream.Seek(0, SeekOrigin.Begin);
+
+        var buffer = new byte[4];
+        _ = stream.Read(buffer);
+
+        Encoding.UTF8.GetString(buffer).Should().Be("Test");
+    }
+
+    [Fact]
+    public async Task TempFileStream_DeletesFileOnDispose()
+    {
+        string path;
+        await using (var stream = new TempFileStream())
+        {
+            path = stream.Name;
+            File.Exists(path).Should().BeTrue();
+        }
+
+        File.Exists(path).Should().BeFalse();
+    }
+}