Fix null or empty string encryption

src/EntityFrameworkCore.DataEncryption/EntityFrameworkCore.DataEncryption.csproj

@@ -7,7 +7,7 @@
 		<AssemblyName>EntityFrameworkCore.DataEncryption</AssemblyName>
 		<RootNamespace>Microsoft.EntityFrameworkCore.DataEncryption</RootNamespace>
 		<IsPackable>true</IsPackable>
-		<Version>4.0.0</Version>
+		<Version>4.0.1</Version>
 		<Authors>Filipe GOMES PEIXOTO</Authors>
 		<PackageId>EntityFrameworkCore.DataEncryption</PackageId>
 		<PackageProjectUrl>https://github.com/Eastrall/EntityFrameworkCore.DataEncryption</PackageProjectUrl>
@@ -20,7 +20,7 @@
 		<Copyright>Filipe GOMES PEIXOTO © 2019 - 2023</Copyright>
 		<Description>A plugin for Microsoft.EntityFrameworkCore to add support of encrypted fields using built-in or custom encryption providers.</Description>
 		<PackageLicenseFile>LICENSE</PackageLicenseFile>
-		<PackageReleaseNotes>https://github.com/Eastrall/EntityFrameworkCore.DataEncryption/releases/tag/v4.0.0</PackageReleaseNotes>
+		<PackageReleaseNotes>https://github.com/Eastrall/EntityFrameworkCore.DataEncryption/releases/tag/v4.0.1</PackageReleaseNotes>
 		<PackageReadmeFile>README.md</PackageReadmeFile>
 	</PropertyGroup>
 

src/EntityFrameworkCore.DataEncryption/Internal/EncryptionConverter.cs

@@ -30,13 +30,18 @@ public EncryptionConverter(IEncryptionProvider encryptionProvider, StorageFormat
     {
         byte[] inputData = input switch
         {
-            string => Encoding.UTF8.GetBytes(input.ToString()),
+            string => !string.IsNullOrEmpty(input.ToString()) ? Encoding.UTF8.GetBytes(input.ToString()) : null,
             byte[] => input as byte[],
             _ => null,
         };
 
         byte[] encryptedRawBytes = encryptionProvider.Encrypt(inputData);
 
+        if (encryptedRawBytes is null)
+        {
+            return default;
+        }
+
         object encryptedData = storageFormat switch
         {
             StorageFormat.Default or StorageFormat.Base64 => Convert.ToBase64String(encryptedRawBytes),

test/EntityFrameworkCore.DataEncryption.Test/PropertyBuilderExtensionsTest.cs

@@ -36,7 +36,8 @@
             Name = name,
             NameAsBytes = name,
             ExtraData = bytes,
-            ExtraDataAsBytes = bytes
+            ExtraDataAsBytes = bytes,
+            EmptyString = ""
         };
 
         using var contextFactory = new DatabaseContextFactory();
@@ -52,6 +53,7 @@
             AssertPropertyAnnotations(entityType.GetProperty(nameof(UserEntity.ExtraData)), true, StorageFormat.Base64);
             AssertPropertyAnnotations(entityType.GetProperty(nameof(UserEntity.ExtraDataAsBytes)), true, StorageFormat.Binary);
             AssertPropertyAnnotations(entityType.GetProperty(nameof(UserEntity.Id)), false, StorageFormat.Default);
+            AssertPropertyAnnotations(entityType.GetProperty(nameof(UserEntity.EmptyString)), true, StorageFormat.Base64);
 
             context.Users.Add(user);
             context.SaveChanges();
@@ -66,6 +68,7 @@
             Assert.Equal(name, u.NameAsBytes);
             Assert.Equal(bytes, u.ExtraData);
             Assert.Equal(bytes, u.ExtraDataAsBytes);
+            Assert.Null(u.EmptyString);
         }
     }
 
@@ -73,21 +76,21 @@
     {
         Assert.NotNull(property);
 
         IAnnotation encryptedAnnotation = property.FindAnnotation(PropertyAnnotations.IsEncrypted);
 
         if (shouldBeEncrypted)
         {
             Assert.NotNull(encryptedAnnotation);
             Assert.True((bool)encryptedAnnotation.Value);
 
             IAnnotation formatAnnotation = property.FindAnnotation(PropertyAnnotations.StorageFormat);
             Assert.NotNull(formatAnnotation);
             Assert.Equal(expectedStorageFormat, formatAnnotation.Value);
         }
         else
         {
             Assert.Null(encryptedAnnotation);
             Assert.Null(property.FindAnnotation(PropertyAnnotations.StorageFormat));
         }
     }
 
@@ -106,6 +109,9 @@
 
         // Encrypted as raw byte array.
         public byte[] ExtraDataAsBytes { get; set; }
+
+        // Encrypt as Base64 string, but will be empty.
+        public string EmptyString { get; set; }
     }
 
     private class FluentDbContext : DbContext
@@ -134,6 +140,7 @@
             userEntityBuilder.Property(x => x.NameAsBytes).IsRequired().HasColumnType("BLOB").IsEncrypted(StorageFormat.Binary);
             userEntityBuilder.Property(x => x.ExtraData).IsRequired().HasColumnType("TEXT").IsEncrypted(StorageFormat.Base64);
             userEntityBuilder.Property(x => x.ExtraDataAsBytes).IsRequired().HasColumnType("BLOB").IsEncrypted(StorageFormat.Binary);
+            userEntityBuilder.Property(x => x.EmptyString).IsRequired(false).HasColumnType("TEXT").IsEncrypted(StorageFormat.Base64);
 
             modelBuilder.UseEncryption(_encryptionProvider);
         }