media upload

Femto.Modules.Media/Infrastructure/FilesystemStorageProvider.cs

@@ -0,0 +1,62 @@
+using Femto.Modules.Media.Data;
+
+namespace Femto.Modules.Media.Infrastructure;
+
+internal class FilesystemStorageProvider : IStorageProvider
+{
+    private readonly string _storageRoot;
+
+    public FilesystemStorageProvider(string storageRoot)
+    {
+        if (string.IsNullOrWhiteSpace(storageRoot))
+            throw new ArgumentException(
+                "Storage root cannot be null or empty.",
+                nameof(storageRoot)
+            );
+
+        this._storageRoot = Path.GetFullPath(storageRoot);
+
+        if (!Directory.Exists(this._storageRoot))
+        {
+            Directory.CreateDirectory(this._storageRoot);
+        }
+    }
+
+    public async Task SaveBlob(string id, Stream data)
+    {
+        string filePath = this.GetSafeFilePath(id);
+
+        // Ensure the directory exists
+        Directory.CreateDirectory(Path.GetDirectoryName(filePath)!);
+
+        await using var fileStream = new FileStream(filePath, FileMode.Create, FileAccess.Write);
+        await data.CopyToAsync(fileStream);
+    }
+
+    public async Task<Stream> LoadBlob(string id)
+    {
+        string filePath = this.GetSafeFilePath(id);
+
+        if (!File.Exists(filePath))
+            throw new FileNotFoundException("The blob with the specified ID was not found.", id);
+
+        Stream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
+
+        return fileStream;
+    }
+
+    private string GetSafeFilePath(string id)
+    {
+        if (string.IsNullOrWhiteSpace(id))
+            throw new ArgumentException("Blob ID cannot be null or empty.", nameof(id));
+
+        // Sanitize and validate the path
+        string combinedPath = Path.Combine(this._storageRoot, id);
+        string fullPath = Path.GetFullPath(combinedPath);
+
+        if (!fullPath.StartsWith(this._storageRoot, StringComparison.Ordinal))
+            throw new UnauthorizedAccessException("Access to the path is denied.");
+
+        return fullPath;
+    }
+}