refactor(StringExtensions): Fehlermeldungen wurden ausgearbeitet und der falsche Variablenname „mode“ wurde in „divisor“ umbenannt.

- Aktualisierte Dokumentationskommentare

DigitalData.Core.Extensions/DigitalData.Core.Extensions.csproj

@@ -1,9 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-	<TargetFrameworks>net7.0;net8.0</TargetFrameworks>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <Nullable>enable</Nullable>
-  </PropertyGroup>
-
-</Project>

DigitalData.Core.Extensions/StringExtensions.cs

@@ -1,13 +0,0 @@
-namespace DigitalData.Core.Extensions
-{
-    public static class StringExtensions
-    {
-        public static string ToBase64String(this byte[] bytes) => Convert.ToBase64String(bytes);
-
-        public static byte[] Base64ToByte(this string base64String) => Convert.FromBase64String(base64String);
-
-        public static byte[] ToBytes(this string str) => System.Text.Encoding.UTF8.GetBytes(str);
-
-        public static string BytesToString(this byte[] bytes) => System.Text.Encoding.UTF8.GetString(bytes);
-    }
-}

DigitalData.Core.Security/AsymCryptService.cs

@@ -31,6 +31,13 @@ namespace DigitalData.Core.Security
             }
         }
 
+        public IRSADecryptor this[int index] => index < 0 || index >= Decryptors.Count()
+            ? Decryptors.ElementAt(index)
+            : throw new ArgumentOutOfRangeException(
+                nameof(index),
+                index,
+                $"The index {index} is out of range. The valid indices for {GetType()} are between 0 and {Decryptors.Count() - 1} (inclusive). Please ensure the index is within this range.");
+
         public AsymCryptService(IOptions<TAsymCryptParams> options, ILogger<AsymCryptService<TAsymCryptParams>>? logger = null) : base(options)
         {
             logger?.LogInformation("Core.Secrets version: {Version}, Created on: {CreationDate}.", Secrets.Version, Secrets.CreationDate.ToString("dd.MM.yyyy"));

DigitalData.Core.Security/Config/AsymCryptParams.cs

@@ -20,6 +20,8 @@ namespace DigitalData.Core.Security.Config
         /// </example>
         public string FileNameSeparator { get; init; } = "_-_";
 
+        public string FileExtension { get; init; } = "pem";
+
         /// <summary>
         /// Represents the separator used to concatenate the components of a key-related token string.
         /// </summary>
@@ -34,13 +36,28 @@ namespace DigitalData.Core.Security.Config
         /// </example>
         public string KeyNameSeparator { get; init; } = ":";
 
+        /// <summary>
+        ///This is the subtext of the pem file name. For the file to be automatically renewed, the name must be assigned to change periodically. For example, by default MM/2 will be refreshed every 2 months.
+        /// <br />
+        /// - <see cref="StringExtensions.ToTag(DateTime, string)" /> is used when converting to tag.
+        /// <br />
+        /// - If the format contains the symbol “//”, the method divides the numeric value obtained from the left side of the format
+        ///   by one minus the numeric value obtained from the right side of the format string and adds one. For instance:
+        /// <br />
+        /// - If the date is 02.03.2024 and the format is "MM//2", it extracts the month (02), subtracts one (3), divides it by 2,
+        ///   rounds down the outgoing number (1), adds one to the number (resulting in 2).
+        ///   <br />
+        /// - If the format does not contain "//", the method uses the default <see cref="DateTime.ToString"/> format.
+        /// <br />
+        /// This method provides a way to format the date based on typical or customized rules, including mathematical operations like division.
+        /// </summary>
+        public string DateTagFormat { get; init; } = "MM//2";
+
         public IEnumerable<RSADecryptor> Decryptors { get; init; } = new List<RSADecryptor>();
 
         public RSADecryptor? Vault { get; init; }
 
-        public AsymCryptParams()
-        {
-            AfterCreate += () =>
+        public AsymCryptParams() => AfterCreate += () =>
             {
                 // Create root folder if it does not exist
                 if (!Directory.Exists(PemDirectory))
@@ -51,11 +68,13 @@ namespace DigitalData.Core.Security.Config
                     // set default path
                     if (decryptor.IsPemNull)
                     {
-                        var file_name_params = new List<object> { decryptor.Issuer, decryptor.Audience };
+                        var file_name_params = new List<object> { decryptor.Issuer, decryptor.Audience, KeySizeInBits, DateTime.Now.ToTag(DateTagFormat) };
                         if (decryptor.IsEncrypted)
                             file_name_params.Add(Secrets.Version);
 
-                        var path = Path.Combine(PemDirectory, string.Join(FileNameSeparator, file_name_params));
+                        var file_name = $"{string.Join(FileNameSeparator, file_name_params)}.{FileExtension}";
+
+                        var path = Path.Combine(PemDirectory, file_name);
 
                         if (File.Exists(path))
                             decryptor.SetPem(File.ReadAllText(path));
@@ -65,7 +84,7 @@ namespace DigitalData.Core.Security.Config
                                 ? Instance.RSAFactory.CreateEncryptedPrivateKeyPem(pbeParameters: PbeParameters, keySizeInBits: KeySizeInBits, password: Secrets.PBE_PASSWORD)
                                 : Instance.RSAFactory.CreatePrivateKeyPem(keySizeInBits: KeySizeInBits);
 
-                            decryptor.SetPem(File.ReadAllText(pem));
+                            decryptor.SetPem(pem);
 
                             // Save file in background
                             Task.Run(async () => await File.WriteAllTextAsync(path: path, pem));
@@ -73,6 +92,5 @@ namespace DigitalData.Core.Security.Config
                     }
                 }
             };
-        }
     }
 }

DigitalData.Core.Security/Config/RSAFactoryParams.cs

@@ -1,4 +1,5 @@
-using System.Security.Cryptography;
+using System.Reflection;
+using System.Security.Cryptography;
 using System.Text.Json.Serialization;
 
 namespace DigitalData.Core.Security.Config
@@ -11,7 +12,16 @@ namespace DigitalData.Core.Security.Config
 
         public PbeEncryptionAlgorithm PbeEncryptionAlgorithm { get; init; } = PbeEncryptionAlgorithm.Aes256Cbc;
 
-        public HashAlgorithmName PbeHashAlgorithmName { get; init; } = HashAlgorithmName.SHA256;
+        public HashAlgorithmName PbeHashAlgorithm { get; init; } = HashAlgorithmName.SHA256;
+
+        // TODO: add as json converter to IConfigurIConfiguration.Config
+        public string PbeHashAlgorithmName
+        {
+            get => PbeHashAlgorithm.ToString();
+            init => PbeHashAlgorithm = (typeof(HashAlgorithmName).GetProperty(value, BindingFlags.Public | BindingFlags.Static)?.GetValue(null) is HashAlgorithmName hashAlgorithmName)
+                ? hashAlgorithmName
+                : new(value);            
+        }
 
         public int PbeIterationCount { get; init; } = 100_000;
 
@@ -37,7 +47,7 @@ namespace DigitalData.Core.Security.Config
                 return true;
             });
 
-            AfterCreate += () => _pbeParameters = new PbeParameters(PbeEncryptionAlgorithm, PbeHashAlgorithmName, PbeIterationCount);
+            AfterCreate += () => _pbeParameters = new PbeParameters(PbeEncryptionAlgorithm, PbeHashAlgorithm, PbeIterationCount);
         }
 
         protected event Action AfterCreate;

DigitalData.Core.Security/Config/StringExtensions.cs

@@ -0,0 +1,83 @@
+namespace DigitalData.Core.Security.Config
+{
+    internal static class StringExtensions
+    {
+        public static string ToBase64String(this byte[] bytes) => Convert.ToBase64String(bytes);
+
+        public static byte[] Base64ToByte(this string base64String) => Convert.FromBase64String(base64String);
+
+        public static byte[] ToBytes(this string str) => System.Text.Encoding.UTF8.GetBytes(str);
+
+        public static string BytesToString(this byte[] bytes) => System.Text.Encoding.UTF8.GetString(bytes);
+
+        /// <summary>
+        /// Converts a <see cref="DateTime"/> to a formatted string based on the specified format string.
+        /// <br />
+        /// - If the format contains the symbol “//”, the method divides the numeric value obtained from the left side of the format
+        ///   by one minus the numeric value obtained from the right side of the format string and adds one. For instance:
+        /// <br />
+        /// - If the date is 02.03.2024 and the format is "MM//2", it extracts the month (02), subtracts one (3), divides it by 2,
+        ///   rounds down the outgoing number (1), adds one to the number (resulting in 2).
+        ///   <br />
+        /// - If the format does not contain "//", the method uses the default <see cref="DateTime.ToString"/> format.
+        /// <br />
+        /// </summary>
+        /// <param name="date">The <see cref="DateTime"/> value to be formatted.</param>
+        /// <param name="format">The format string that dictates the formatting of the date. If the format includes the "//" symbol, 
+        /// it splits the string at "//" and divides the left-side value by the right-side value. The format string can include standard
+        /// <see cref="DateTime.ToString"/> format patterns.</param>
+        /// <returns>A string representation of the formatted date, or the result of the division operation if "//" is present in the format.</returns>
+        /// <exception cref="ArgumentException">Thrown if the format string is invalid, such as having an incorrect number of parts after "//".</exception>
+        /// <exception cref="DivideByZeroException">Thrown if the right side of the "//" contains a zero, resulting in division by zero.</exception>
+        /// <exception cref="FormatException">Thrown if either the left-side or right-side value of "//" cannot be parsed as an integer.</exception>
+        public static string ToTag(this DateTime date, string format)
+        {
+            if (format is not null && format.Contains("//"))
+            {
+                var subStrings = format.Split("//");
+
+                if (subStrings.Length != 2)
+                    throw new ArgumentException($"Date tag format {format} is invalid. It must contain exactly one '//' separator.", nameof(format));
+
+                var formattedLeft = date.ToString(subStrings[0]);
+
+                if (!int.TryParse(formattedLeft, out var dateValue))
+                    throw new FormatException($"The left-side value ({formattedLeft}) of the format could not be parsed to an integer.");
+
+                if (!int.TryParse(subStrings[1], out var divisor))
+                    throw new FormatException($"The right-side value ({divisor}) of the format could not be parsed to an integer.");
+
+                if (divisor == 0)
+                    throw new DivideByZeroException($"Date tag format {format} includes division by zero, which is not allowed.");
+
+                var result = (dateValue - 1) / divisor + 1;
+                return result.ToString();
+            }
+
+            return date.ToString(format);
+        }
+
+        /// <summary>
+        /// Converts a <see cref="DateTime"/> to a formatted string based on the specified format string.
+        /// <br />
+        /// - If the format contains the symbol “//”, the method divides the numeric value obtained from the left side of the format
+        ///   by one minus the numeric value obtained from the right side of the format string and adds one. For instance:
+        /// <br />
+        /// - If the date is 02.03.2024 and the format is "MM//2", it extracts the month (02), subtracts one (3), divides it by 2,
+        ///   rounds down the outgoing number (1), adds one to the number (resulting in 2).
+        ///   <br />
+        /// - If the format does not contain "//", the method uses the default <see cref="DateTime.ToString"/> format.
+        /// <br />
+        /// This method provides a way to format the date based on typical or customized rules, including mathematical operations like division.
+        /// </summary>
+        /// <param name="date">The <see cref="DateOnly"/> value to be formatted. It will convert to DateTime to use the method shared with DateTime.</param>
+        /// <param name="format">The format string that dictates the formatting of the date. If the format includes the "//" symbol, 
+        /// it splits the string at "//" and divides the left-side value by the right-side value. The format string can include standard
+        /// <see cref="DateTime.ToString"/> format patterns.</param>
+        /// <returns>A string representation of the formatted date, or the result of the division operation if "//" is present in the format.</returns>
+        /// <exception cref="ArgumentException">Thrown if the format string is invalid, such as having an incorrect number of parts after "//".</exception>
+        /// <exception cref="DivideByZeroException">Thrown if the right side of the "//" contains a zero, resulting in division by zero.</exception>
+        /// <exception cref="FormatException">Thrown if either the left-side or right-side value of "//" cannot be parsed as an integer.</exception>
+        public static string ToTag(this DateOnly date, string format) => date.ToDateTime(new()).ToTag(format);
+    }
+}

DigitalData.Core.Security/Cryptographer/RSACryptographer.cs

@@ -1,4 +1,5 @@
 using DigitalData.Core.Abstractions.Security;
+using System.Reflection;
 using System.Security.Cryptography;
 
 namespace DigitalData.Core.Security.Cryptographer
@@ -10,6 +11,13 @@ namespace DigitalData.Core.Security.Cryptographer
                 
         public RSAEncryptionPadding Padding { get; init; } = RSAEncryptionPadding.OaepSHA256;
 
+        // TODO: add as json converter to IConfigurIConfiguration.Config
+        public string PaddingName
+        {
+            get => Padding.ToString();
+            init => Padding = typeof(RSAEncryptionPadding).GetProperty(value, BindingFlags.Public | BindingFlags.Static)?.GetValue(null) as RSAEncryptionPadding ?? throw new ArgumentException($"Padding '{value}' not found.");
+        }
+
         protected virtual RSA RSA { get; } = RSA.Create();
 
         public string Issuer { get; init; } = string.Empty;

DigitalData.Core.Security/Cryptographer/RSADecryptor.cs

@@ -1,5 +1,5 @@
 using DigitalData.Core.Abstractions.Security;
-using DigitalData.Core.Extensions;
+using DigitalData.Core.Security.Config;
 using System.Security.Cryptography;
 
 namespace DigitalData.Core.Security.Cryptographer
@@ -10,7 +10,9 @@ namespace DigitalData.Core.Security.Cryptographer
 
         public override string Pem
         {
-            get => _pem ?? throw PemIsNullException;
+#pragma warning disable CS8603 // Possible null reference return.
+            get => _pem;
+#pragma warning restore CS8603 // Possible null reference return.
             init
             {
                 _pem = value;

DigitalData.Core.Security/Cryptographer/RSAEncryptor.cs

@@ -1,5 +1,5 @@
 using DigitalData.Core.Abstractions.Security;
-using DigitalData.Core.Extensions;
+using DigitalData.Core.Security.Config;
 
 namespace DigitalData.Core.Security.Cryptographer
 {
@@ -17,7 +17,7 @@ namespace DigitalData.Core.Security.Cryptographer
 
         public byte[] Encrypt(byte[] data) => RSA.Encrypt(data, Padding);
 
-        public string Encrypt(string data) => RSA.Encrypt(data.Base64ToByte(), Padding).BytesToString();
+        public string Encrypt(string data) => RSA.Encrypt(data.ToBytes(), Padding).ToBase64String();
 
         public bool Verify(string data, string signature) => Encrypt(data) == signature;
     }

DigitalData.Core.Security/Cryptographer/RSAFactory.cs

@@ -31,7 +31,7 @@ namespace DigitalData.Core.Security.Cryptographer
             var pbeParameters = pbeEncryptionAlgorithm is null && hashAlgorithmName is null && iterationCount is null
                 ? new PbeParameters(
                     pbeEncryptionAlgorithm ?? _params.PbeEncryptionAlgorithm,
-                    hashAlgorithmName ?? _params.PbeHashAlgorithmName,
+                    hashAlgorithmName ?? _params.PbeHashAlgorithm,
                     iterationCount ?? _params.PbeIterationCount)
                 : _params.PbeParameters;
 

DigitalData.Core.Security/DIExtensions.cs

@@ -4,23 +4,11 @@ using DigitalData.Core.Security.Cryptographer;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Options;
-using System.Text.Json;
-using System.Text.Json.Serialization;
 
 namespace DigitalData.Core.Security
 {
     public static class DIExtensions
     {
-        public static JsonSerializerOptions AddCryptographerConverter(this JsonSerializerOptions options)
-        {
-            if (!options.Converters.OfType<HashAlgorithmNameConverter>().Any())
-                options.Converters.Add(new HashAlgorithmNameConverter());
-
-            if (!options.Converters.OfType<JsonStringEnumConverter>().Any())
-                options.Converters.Add(new JsonStringEnumConverter());
-            return options;
-        }
-
         private static IServiceCollection AddParamsConfigureOptions<TParams>(this IServiceCollection services) where TParams : RSAFactoryParams
             => services.AddSingleton<IConfigureOptions<TParams>, ParamsConfigureOptions<TParams>>();
 

DigitalData.Core.Security/DigitalData.Core.Security.csproj

@@ -12,7 +12,6 @@
 
   <ItemGroup>
     <ProjectReference Include="..\DigitalData.Core.Abstractions\DigitalData.Core.Abstractions.csproj" />
-    <ProjectReference Include="..\DigitalData.Core.Extensions\DigitalData.Core.Extensions.csproj" />
   </ItemGroup>
 
 </Project>

DigitalData.Core.Security/HashAlgorithmNameConverter.cs

@@ -1,13 +0,0 @@
-using System.Security.Cryptography;
-using System.Text.Json.Serialization;
-using System.Text.Json;
-
-namespace DigitalData.Core.Security
-{
-    public class HashAlgorithmNameConverter : JsonConverter<HashAlgorithmName>
-    {
-        public override HashAlgorithmName Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) => new(reader.GetString() ?? string.Empty);
-
-        public override void Write(Utf8JsonWriter writer, HashAlgorithmName value, JsonSerializerOptions options) => writer.WriteStringValue(value.Name);
-    }
-}

DigitalData.Core.sln

@@ -25,7 +25,7 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DigitalData.Core.Security",
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DigitalData.Core.Terminal", "DigitalData.Core.Terminal\DigitalData.Core.Terminal.csproj", "{0FA93730-8084-4907-B172-87D610323796}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DigitalData.Core.Extensions", "DigitalData.Core.Extensions\DigitalData.Core.Extensions.csproj", "{FC6AD1C4-5D7C-4B50-9330-B7A0E52B24B8}"
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DigitalData.Core.Tests.API", "DigitalData.Core.Tests.API\DigitalData.Core.Tests.API.csproj", "{9BC2DEC5-E89D-48CC-9A51-4D94496EE4A6}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -76,10 +76,10 @@ Global
 		{0FA93730-8084-4907-B172-87D610323796}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{0FA93730-8084-4907-B172-87D610323796}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{0FA93730-8084-4907-B172-87D610323796}.Release|Any CPU.Build.0 = Release|Any CPU
-		{FC6AD1C4-5D7C-4B50-9330-B7A0E52B24B8}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{FC6AD1C4-5D7C-4B50-9330-B7A0E52B24B8}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{FC6AD1C4-5D7C-4B50-9330-B7A0E52B24B8}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{FC6AD1C4-5D7C-4B50-9330-B7A0E52B24B8}.Release|Any CPU.Build.0 = Release|Any CPU
+		{9BC2DEC5-E89D-48CC-9A51-4D94496EE4A6}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{9BC2DEC5-E89D-48CC-9A51-4D94496EE4A6}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{9BC2DEC5-E89D-48CC-9A51-4D94496EE4A6}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{9BC2DEC5-E89D-48CC-9A51-4D94496EE4A6}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE