KeysetEngine.DataProtection API Reference

Namespace: KeysetEngine.DataProtection

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Interfaces

ICursorProtector

Abstraction for encrypting and decrypting keyset cursor tokens.

namespace KeysetEngine.Core;

public interface ICursorProtector
{
    string Protect(KeysetCursorToken token, string entityPurpose);
    KeysetCursorToken? Unprotect(string? opaqueCursor, string entityPurpose);
}

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Implementations

DataProtectionCursorProtector

Protects and unprotects cursor tokens using ASP.NET Core Data Protection (IDataProtectionProvider).

public sealed class DataProtectionCursorProtector : ICursorProtector
{
    public DataProtectionCursorProtector(IDataProtectionProvider provider);

    public string Protect(KeysetCursorToken token, string entityPurpose);
    public KeysetCursorToken? Unprotect(string? opaqueCursor, string entityPurpose);
}

Behavior

• Uses sub-purpose hierarchy: provider.CreateProtector("KeysetEngine", entityPurpose, "v1").
• Resiliently catches CryptographicException, FormatException, and JsonException, returning null rather than throwing errors.

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Base64UrlCursorProtector

Lightweight, non-cryptographic implementation available in KeysetEngine.Core for testing.

public sealed class Base64UrlCursorProtector : ICursorProtector
{
    public static Base64UrlCursorProtector Instance { get; }
}

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Dependency Injection Extensions

KeysetDataProtectionServiceCollectionExtensions

public static IServiceCollection AddKeysetDataProtection(this IServiceCollection services);

Registers DataProtectionCursorProtector as a singleton implementation of ICursorProtector. Requires services.AddDataProtection() to be configured.