Custom ServiceUrl for S3 compatible services

src/FubarDev.FtpServer.FileSystem.S3/S3FileSystem.cs

@@ -34,10 +34,19 @@ public sealed class S3FileSystem : IUnixFileSystem
         public S3FileSystem(S3FileSystemOptions options, string rootDirectory)
         {
             _options = options;
-            _client = new AmazonS3Client(
-                options.AwsAccessKeyId,
-                options.AwsSecretAccessKey,
-                RegionEndpoint.GetBySystemName(options.BucketRegion));
+
+            var config = new AmazonS3Config();
+
+            if (!string.IsNullOrEmpty(options.ServiceUrl))
+            {
+                config.ServiceURL = options.ServiceUrl;
+            }
+            else
+            {
+                config.RegionEndpoint = RegionEndpoint.GetBySystemName(options.BucketRegion);
+            }
+
+            _client = new AmazonS3Client(options.AwsAccessKeyId, options.AwsSecretAccessKey, config);
             Root = new S3DirectoryEntry(rootDirectory, true);
             _transferUtility = new TransferUtility(_client);
         }

src/FubarDev.FtpServer.FileSystem.S3/S3FileSystemOptions.cs

@@ -32,6 +32,14 @@ public class S3FileSystemOptions
         /// </remarks>
         public string? BucketRegion { get; set; }
 
+        /// <summary>
+        /// Gets or sets the S3 service URL.
+        /// </summary>
+        /// <remarks>
+        /// Takes precedence over BucketRegion.
+        /// </remarks>
+        public string? ServiceUrl { get; set; }
+
         /// <summary>
         /// Gets or sets the S3 bucket name.
         /// </summary>

src/FubarDev.FtpServer.FileSystem.S3/S3FileSystemProvider.cs

@@ -31,7 +31,7 @@ public S3FileSystemProvider(IOptions<S3FileSystemOptions> options, IAccountDirec
             if (string.IsNullOrEmpty(_options.AwsAccessKeyId)
                 || string.IsNullOrEmpty(_options.AwsSecretAccessKey)
                 || string.IsNullOrEmpty(_options.BucketName)
-                || string.IsNullOrEmpty(_options.BucketRegion))
+                || (string.IsNullOrEmpty(_options.BucketRegion) && string.IsNullOrEmpty(_options.ServiceUrl)))
             {
                 throw new ArgumentException("S3 Credentials have not been set correctly");
             }