(feature): add HA work leases and pub/sub helpers for v2.1.0

CHANGELOG.md

@@ -5,6 +5,18 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.1.0] - 2026-07-30
+
+### Added
+- **HA work leases via Dapr state:** `IDaprWorkLeaseStore` / `DaprWorkLeaseStore` (acquire, renew, release, get) using ETag concurrency — broker-agnostic (NATS KV / Postgres / other state Component).
+- **State ETag API:** `GetStateAndETagAsync` and `TrySaveStateAsync` on `IDaprStateStoreService`.
+- **Runtime instance id:** `IDaprRuntimeInstanceId` / `DaprRuntimeInstanceIdProvider` (`POD_NAME` in Kubernetes).
+- **Pub/sub worker helpers:** `IDaprPubSubWorkHandler<T>`, `DaprPubSubAcceptOutcome` / `DaprPubSubAcceptResult`, `DaprPubSubAck` (HTTP ACK/NAK mapping).
+- DI: `RegisterWorkLeases()` registers state store + lease store + instance id.
+
+### Changed
+- Package version **2.1.0**.
+
 ## [2.0.1] - 2026-06-28
 
 ### Changed
@@ -25,27 +37,3 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Removed
 - Legacy root-level release scripts (`Release-NuGetPackage.*`) in favor of the `utils/Release-NuGetPackage/` flow.
-
-<!-- 
-Template for new releases:
-
-## v1.x.x
-
-### Added
-- New features
-
-### Changed
-- Changes in existing functionality
-
-### Deprecated
-- Soon-to-be removed features
-
-### Removed
-- Removed features
-
-### Fixed
-- Bug fixes
-
-### Security
-- Security improvements
--->

README.md

@@ -67,6 +67,8 @@ var builder = WebApplication.CreateBuilder(args);
 // Register Dapr services
 builder.Services.RegisterPublisher();
 builder.Services.RegisterStateStore();
+// HA coordination (leases via Dapr state Component — e.g. persistent NATS KV)
+builder.Services.RegisterWorkLeases();
 
 var app = builder.Build();
 
@@ -166,6 +168,28 @@ public class MyService
 
 This setup enables your ASP.NET Core application to utilize Dapr's pub-sub, state management, and other building blocks with minimal boilerplate.
 
+### HA work leases (multi-replica)
+
+Use Dapr **state** (not product DB lock tables) for bootstrap/sweep/holder coordination. The state Component is infrastructure (e.g. persistent NATS JetStream KV); application code stays broker-agnostic.
+
+```csharp
+builder.Services.RegisterWorkLeases();
+
+// inject IDaprWorkLeaseStore + IDaprRuntimeInstanceId
+var acquired = await leases.TryAcquireAsync(
+  storeName: "maksit-cicd-state",
+  workKey: "bootstrap",
+  holderId: runtimeInstance.InstanceId,
+  ttl: TimeSpan.FromMinutes(5),
+  ct);
+
+if (acquired is { IsSuccess: true, Value: true }) {
+  try { /* exclusive work */ }
+  finally { await leases.ReleaseAsync("maksit-cicd-state", "bootstrap", runtimeInstance.InstanceId, CancellationToken.None); }
+}
+```
+
+Pub/sub workers: implement `IDaprPubSubWorkHandler<T>` and map with `DaprPubSubAck.ToActionResult` (2xx ACK, 503 Busy → redelivery).
 
 ## Contributing
 

src/MaksIT.Dapr.Tests/DaprWorkLeaseStoreTests.cs

@@ -0,0 +1,82 @@
+using Dapr.Client;
+using MaksIT.Dapr.PubSub;
+using MaksIT.Dapr.Services;
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Logging;
+using Moq;
+
+
+namespace MaksIT.Dapr.Tests;
+
+public class DaprWorkLeaseStoreTests {
+  [Fact]
+  public async Task TryAcquireAsync_Succeeds_WhenKeyMissing() {
+    var state = new Mock<IDaprStateStoreService>();
+    state
+      .Setup(s => s.GetStateAndETagAsync<DaprWorkLease>("store", "work", It.IsAny<CancellationToken>()))
+      .ReturnsAsync(MaksIT.Results.Result<(DaprWorkLease? Value, string? ETag)>.Ok((null, null)));
+    state
+      .Setup(s => s.TrySaveStateAsync("store", "work", It.IsAny<DaprWorkLease>(), null, It.IsAny<CancellationToken>()))
+      .ReturnsAsync(MaksIT.Results.Result<bool>.Ok(true));
+
+    var store = new DaprWorkLeaseStore(state.Object);
+    var result = await store.TryAcquireAsync("store", "work", "pod-a", TimeSpan.FromMinutes(1));
+
+    Assert.True(result.IsSuccess);
+    Assert.True(result.Value);
+  }
+
+  [Fact]
+  public async Task TryAcquireAsync_Fails_WhenHeldByOtherAndNotExpired() {
+    var lease = new DaprWorkLease("pod-b", DateTimeOffset.UtcNow, DateTimeOffset.UtcNow.AddMinutes(5));
+    var state = new Mock<IDaprStateStoreService>();
+    state
+      .Setup(s => s.GetStateAndETagAsync<DaprWorkLease>("store", "work", It.IsAny<CancellationToken>()))
+      .ReturnsAsync(MaksIT.Results.Result<(DaprWorkLease? Value, string? ETag)>.Ok((lease, "1")));
+
+    var store = new DaprWorkLeaseStore(state.Object);
+    var result = await store.TryAcquireAsync("store", "work", "pod-a", TimeSpan.FromMinutes(1));
+
+    Assert.True(result.IsSuccess);
+    Assert.False(result.Value);
+  }
+}
+
+public class DaprPubSubAckTests {
+  [Fact]
+  public void ToActionResult_Busy_Returns503() {
+    var result = DaprPubSubAck.ToActionResult(DaprPubSubAcceptResult.Busy("full"));
+    var objectResult = Assert.IsType<ObjectResult>(result);
+    Assert.Equal(StatusCodes.Status503ServiceUnavailable, objectResult.StatusCode);
+  }
+
+  [Fact]
+  public void ToActionResult_Accepted_Returns200() {
+    var result = DaprPubSubAck.ToActionResult(DaprPubSubAcceptResult.Accepted());
+    Assert.IsType<OkObjectResult>(result);
+  }
+}
+
+public class DaprStateStoreETagTests {
+  [Fact]
+  public async Task TrySaveStateAsync_ReturnsOkFalse_WhenClientReturnsFalse() {
+    var clientMock = new Mock<DaprClient>();
+    clientMock
+      .Setup(x => x.TrySaveStateAsync(
+        It.IsAny<string>(),
+        It.IsAny<string>(),
+        It.IsAny<string>(),
+        It.IsAny<string>(),
+        It.IsAny<StateOptions>(),
+        It.IsAny<IReadOnlyDictionary<string, string>>(),
+        It.IsAny<CancellationToken>()))
+      .ReturnsAsync(false);
+
+    var service = new DaprStateStoreService(Mock.Of<ILogger<DaprStateStoreService>>(), clientMock.Object);
+    var result = await service.TrySaveStateAsync("store", "key", "value", "etag");
+
+    Assert.True(result.IsSuccess);
+    Assert.False(result.Value);
+  }
+}

src/MaksIT.Dapr/Extensions/ServiceCollectionExtensions.cs

@@ -5,13 +5,14 @@ using Microsoft.Extensions.DependencyInjection;
 namespace MaksIT.Dapr.Extensions;
 
 public static class ServiceCollectionExtensions {
-  private static bool _isDaprClientRegistered = false;
+  private static bool _isDaprClientRegistered;
 
   private static void AddDaprClientOnce(this IServiceCollection services) {
-    if (!_isDaprClientRegistered) {
+    if (_isDaprClientRegistered)
-      services.AddDaprClient();
+      return;
-      _isDaprClientRegistered = true;
+
-    }
+    services.AddDaprClient();
+    _isDaprClientRegistered = true;
   }
 
   public static void RegisterPublisher(this IServiceCollection services) {
@@ -23,4 +24,13 @@ public static class ServiceCollectionExtensions {
     services.AddDaprClientOnce();
     services.AddSingleton<IDaprStateStoreService, DaprStateStoreService>();
   }
-}
+
+  /// <summary>
+  /// Registers Dapr state store plus HA work-lease coordination and runtime instance id.
+  /// </summary>
+  public static void RegisterWorkLeases(this IServiceCollection services) {
+    services.RegisterStateStore();
+    services.AddSingleton<IDaprRuntimeInstanceId, DaprRuntimeInstanceIdProvider>();
+    services.AddSingleton<IDaprWorkLeaseStore, DaprWorkLeaseStore>();
+  }
+}

src/MaksIT.Dapr/MaksIT.Dapr.csproj

@@ -7,7 +7,7 @@
 
     <!-- NuGet package metadata -->
     <PackageId>MaksIT.Dapr</PackageId>
-    <Version>2.0.1</Version>
+    <Version>2.1.0</Version>
     <Authors>Maksym Sadovnychyy</Authors>
     <Company>MAKS-IT</Company>
     <Product>MaksIT.Dapr</Product>

src/MaksIT.Dapr/PubSub/DaprPubSubWork.cs

@@ -0,0 +1,45 @@
+using Microsoft.AspNetCore.Http;
+using Microsoft.AspNetCore.Mvc;
+
+
+namespace MaksIT.Dapr.PubSub;
+
+public enum DaprPubSubAcceptOutcome {
+  Accepted = 0,
+  AlreadyHandled = 1,
+  Busy = 2,
+  Rejected = 3,
+}
+
+public sealed record DaprPubSubAcceptResult(DaprPubSubAcceptOutcome Outcome, string? Detail = null) {
+  public static DaprPubSubAcceptResult Accepted(string? detail = null) => new(DaprPubSubAcceptOutcome.Accepted, detail);
+  public static DaprPubSubAcceptResult AlreadyHandled(string? detail = null) => new(DaprPubSubAcceptOutcome.AlreadyHandled, detail);
+  public static DaprPubSubAcceptResult Busy(string? detail = null) => new(DaprPubSubAcceptOutcome.Busy, detail);
+  public static DaprPubSubAcceptResult Rejected(string? detail = null) => new(DaprPubSubAcceptOutcome.Rejected, detail);
+}
+
+/// <summary>Product implements accept/claim; HTTP layer maps to Dapr ACK/NAK via <see cref="DaprPubSubAck"/>.</summary>
+public interface IDaprPubSubWorkHandler<TMessage> {
+  Task<DaprPubSubAcceptResult> TryAcceptAsync(TMessage message, CancellationToken cancellationToken = default);
+}
+
+/// <summary>Maps accept outcomes to HTTP status codes for Dapr pub/sub delivery.</summary>
+public static class DaprPubSubAck {
+  public static IActionResult ToActionResult(DaprPubSubAcceptResult result) =>
+    result.Outcome switch {
+      DaprPubSubAcceptOutcome.Accepted => new OkObjectResult(new { status = "accepted", detail = result.Detail }),
+      DaprPubSubAcceptOutcome.AlreadyHandled => new OkObjectResult(new { status = "alreadyHandled", detail = result.Detail }),
+      DaprPubSubAcceptOutcome.Busy => new ObjectResult(new { status = "busy", detail = result.Detail }) { StatusCode = StatusCodes.Status503ServiceUnavailable },
+      DaprPubSubAcceptOutcome.Rejected => new BadRequestObjectResult(new { status = "rejected", detail = result.Detail }),
+      _ => new StatusCodeResult(StatusCodes.Status500InternalServerError),
+    };
+
+  public static Microsoft.AspNetCore.Http.IResult ToHttpResult(DaprPubSubAcceptResult result) =>
+    result.Outcome switch {
+      DaprPubSubAcceptOutcome.Accepted => Microsoft.AspNetCore.Http.Results.Ok(new { status = "accepted", detail = result.Detail }),
+      DaprPubSubAcceptOutcome.AlreadyHandled => Microsoft.AspNetCore.Http.Results.Ok(new { status = "alreadyHandled", detail = result.Detail }),
+      DaprPubSubAcceptOutcome.Busy => Microsoft.AspNetCore.Http.Results.Json(new { status = "busy", detail = result.Detail }, statusCode: StatusCodes.Status503ServiceUnavailable),
+      DaprPubSubAcceptOutcome.Rejected => Microsoft.AspNetCore.Http.Results.BadRequest(new { status = "rejected", detail = result.Detail }),
+      _ => Microsoft.AspNetCore.Http.Results.StatusCode(StatusCodes.Status500InternalServerError),
+    };
+}

src/MaksIT.Dapr/Services/DaprRuntimeInstanceIdProvider.cs

@@ -0,0 +1,26 @@
+namespace MaksIT.Dapr.Services;
+
+/// <summary>Stable id for this process/pod (lease holder).</summary>
+public interface IDaprRuntimeInstanceId {
+  string InstanceId { get; }
+}
+
+/// <summary>
+/// Prefers <c>POD_NAME</c> in Kubernetes; otherwise host name + process id.
+/// </summary>
+public sealed class DaprRuntimeInstanceIdProvider : IDaprRuntimeInstanceId {
+  public string InstanceId { get; } = Build();
+
+  private static string Build() {
+    var logicalHost =
+      Environment.GetEnvironmentVariable("POD_NAME")
+      ?? Environment.GetEnvironmentVariable("HOSTNAME")
+      ?? Environment.GetEnvironmentVariable("COMPUTERNAME")
+      ?? Environment.MachineName;
+
+    if (!string.IsNullOrEmpty(Environment.GetEnvironmentVariable("KUBERNETES_SERVICE_HOST")))
+      return logicalHost;
+
+    return $"{logicalHost}-{Environment.ProcessId}";
+  }
+}

src/MaksIT.Dapr/Services/DaprStateStoreService.cs

@@ -1,85 +1,93 @@
-using Microsoft.Extensions.Logging;
+using Dapr.Client;
-
-using Dapr.Client;
-
-using MaksIT.Results;
 using MaksIT.Core.Extensions;
+using MaksIT.Results;
+using Microsoft.Extensions.Logging;
+
 
 namespace MaksIT.Dapr.Services;
+
 public interface IDaprStateStoreService {
   Task<Result> SetStateAsync<T>(string storeName, string key, T value);
   Task<Result<T?>> GetStateAsync<T>(string storeName, string key);
+  Task<Result<(T? Value, string? ETag)>> GetStateAndETagAsync<T>(string storeName, string key, CancellationToken cancellationToken = default);
+  Task<Result<bool>> TrySaveStateAsync<T>(string storeName, string key, T value, string? etag, CancellationToken cancellationToken = default);
   Task<Result> DeleteStateAsync(string storeName, string key);
 }
 
-
 public class DaprStateStoreService : IDaprStateStoreService {
-  private const string _errorMessage = "MaksIT.Dapr - Data provider error";
+  private const string ErrorMessage = "MaksIT.Dapr - Data provider error";
 
   private readonly DaprClient _client;
   private readonly ILogger<DaprStateStoreService> _logger;
 
-  public DaprStateStoreService(
+  public DaprStateStoreService(ILogger<DaprStateStoreService> logger, DaprClient client) {
-    ILogger<DaprStateStoreService> logger,
-    DaprClient client
-  ) {
     _logger = logger;
     _client = client;
   }
-  /// <summary>
+
-  /// Saves a state to a Dapr state store
-  /// </summary>
-  /// <typeparam name="T"></typeparam>
-  /// <param name="storeName"></param>
-  /// <param name="key"></param>
-  /// <param name="value"></param>
-  /// <returns></returns>
   public async Task<Result> SetStateAsync<T>(string storeName, string key, T value) {
     try {
       await _client.SaveStateAsync(storeName, key, value);
       return Result.Ok();
     }
     catch (Exception ex) {
-      _logger.LogError(ex, _errorMessage);
+      _logger.LogError(ex, ErrorMessage);
-      return Result.InternalServerError(new[] {_errorMessage}.Concat(ex.ExtractMessages()).ToArray());
+      return Result.InternalServerError([ErrorMessage, .. ex.ExtractMessages()]);
     }
   }
 
-  /// <summary>
-  /// Gets a state from a Dapr state store
-  /// </summary>
-  /// <typeparam name="T"></typeparam>
-  /// <param name="storeName"></param>
-  /// <param name="key"></param>
-  /// <returns></returns>
   public async Task<Result<T?>> GetStateAsync<T>(string storeName, string key) {
     try {
       var state = await _client.GetStateAsync<T?>(storeName, key);
-      if (state == null)
+      if (state is null)
         return Result<T?>.NotFound(default, $"State from the store {storeName} with the {key} not found.");
 
       return Result<T?>.Ok(state);
     }
     catch (Exception ex) {
-      _logger.LogError(ex, _errorMessage);
+      _logger.LogError(ex, ErrorMessage);
-      return Result<T?>.InternalServerError(default, new[] {_errorMessage}.Concat(ex.ExtractMessages()).ToArray());
+      return Result<T?>.InternalServerError(default, [ErrorMessage, .. ex.ExtractMessages()]);
+    }
+  }
+
+  public async Task<Result<(T? Value, string? ETag)>> GetStateAndETagAsync<T>(
+    string storeName,
+    string key,
+    CancellationToken cancellationToken = default) {
+    try {
+      var (value, etag) = await _client.GetStateAndETagAsync<T?>(storeName, key, cancellationToken: cancellationToken);
+      return Result<(T? Value, string? ETag)>.Ok((value, etag));
+    }
+    catch (Exception ex) {
+      _logger.LogError(ex, ErrorMessage);
+      return Result<(T? Value, string? ETag)>.InternalServerError(default, [ErrorMessage, .. ex.ExtractMessages()]);
+    }
+  }
+
+  public async Task<Result<bool>> TrySaveStateAsync<T>(
+    string storeName,
+    string key,
+    T value,
+    string? etag,
+    CancellationToken cancellationToken = default) {
+    try {
+      var saved = await _client.TrySaveStateAsync(storeName, key, value, etag ?? string.Empty, cancellationToken: cancellationToken);
+      return Result<bool>.Ok(saved);
+    }
+    catch (Exception ex) {
+      _logger.LogError(ex, ErrorMessage);
+      return Result<bool>.InternalServerError(false, [ErrorMessage, .. ex.ExtractMessages()]);
     }
   }
 
-  /// <summary>
-  /// Deletes a state from a Dapr state store
-  /// </summary>
-  /// <param name="storeName"></param>
-  /// <param name="key"></param>
-  /// <returns></returns>
   public async Task<Result> DeleteStateAsync(string storeName, string key) {
     try {
       await _client.DeleteStateAsync(storeName, key);
       return Result.Ok();
     }
     catch (Exception ex) {
-      _logger.LogError(ex, _errorMessage);
+      _logger.LogError(ex, ErrorMessage);
-      return Result.InternalServerError([_errorMessage, .. ex.ExtractMessages()]);
+      return Result.InternalServerError([ErrorMessage, .. ex.ExtractMessages()]);
     }
   }
-}
+}

src/MaksIT.Dapr/Services/DaprWorkLeaseStore.cs

@@ -0,0 +1,126 @@
+using MaksIT.Results;
+
+
+namespace MaksIT.Dapr.Services;
+
+public sealed record DaprWorkLease(
+  string HolderId,
+  DateTimeOffset AcquiredAtUtc,
+  DateTimeOffset ExpiresAtUtc
+);
+
+/// <summary>
+/// HA work coordination via Dapr state store (broker-agnostic).
+/// Keys are product-defined; store name comes from the Dapr Component.
+/// </summary>
+public interface IDaprWorkLeaseStore {
+  Task<Result<bool>> TryAcquireAsync(string storeName, string workKey, string holderId, TimeSpan ttl, CancellationToken cancellationToken = default);
+  Task<Result<bool>> TryRenewAsync(string storeName, string workKey, string holderId, TimeSpan ttl, CancellationToken cancellationToken = default);
+  Task<Result> ReleaseAsync(string storeName, string workKey, string holderId, CancellationToken cancellationToken = default);
+  Task<Result<DaprWorkLease?>> GetAsync(string storeName, string workKey, CancellationToken cancellationToken = default);
+}
+
+public sealed class DaprWorkLeaseStore(
+  IDaprStateStoreService stateStore
+) : IDaprWorkLeaseStore {
+
+  public async Task<Result<bool>> TryAcquireAsync(
+    string storeName,
+    string workKey,
+    string holderId,
+    TimeSpan ttl,
+    CancellationToken cancellationToken = default) {
+    var validation = Validate(storeName, workKey, holderId, ttl);
+    if (!validation.IsSuccess)
+      return validation.ToResultOfType<bool>(false);
+
+    var existing = await stateStore.GetStateAndETagAsync<DaprWorkLease>(storeName, workKey, cancellationToken).ConfigureAwait(false);
+    if (!existing.IsSuccess)
+      return existing.ToResult().ToResultOfType<bool>(false);
+
+    var (lease, etag) = existing.Value;
+    var now = DateTimeOffset.UtcNow;
+
+    if (lease is not null && lease.ExpiresAtUtc > now && !string.Equals(lease.HolderId, holderId, StringComparison.Ordinal))
+      return Result<bool>.Ok(false);
+
+    var next = new DaprWorkLease(holderId, now, now.Add(ttl));
+    // First write: etag may be null/empty when key missing.
+    var saved = await stateStore.TrySaveStateAsync(storeName, workKey, next, etag, cancellationToken).ConfigureAwait(false);
+    if (!saved.IsSuccess)
+      return saved;
+
+    return Result<bool>.Ok(saved.Value);
+  }
+
+  public async Task<Result<bool>> TryRenewAsync(
+    string storeName,
+    string workKey,
+    string holderId,
+    TimeSpan ttl,
+    CancellationToken cancellationToken = default) {
+    var validation = Validate(storeName, workKey, holderId, ttl);
+    if (!validation.IsSuccess)
+      return validation.ToResultOfType<bool>(false);
+
+    var existing = await stateStore.GetStateAndETagAsync<DaprWorkLease>(storeName, workKey, cancellationToken).ConfigureAwait(false);
+    if (!existing.IsSuccess)
+      return existing.ToResult().ToResultOfType<bool>(false);
+
+    var (lease, etag) = existing.Value;
+    if (lease is null || !string.Equals(lease.HolderId, holderId, StringComparison.Ordinal))
+      return Result<bool>.Ok(false);
+
+    var now = DateTimeOffset.UtcNow;
+    var next = lease with { ExpiresAtUtc = now.Add(ttl) };
+    var saved = await stateStore.TrySaveStateAsync(storeName, workKey, next, etag, cancellationToken).ConfigureAwait(false);
+    if (!saved.IsSuccess)
+      return saved;
+
+    return Result<bool>.Ok(saved.Value);
+  }
+
+  public async Task<Result> ReleaseAsync(
+    string storeName,
+    string workKey,
+    string holderId,
+    CancellationToken cancellationToken = default) {
+    if (string.IsNullOrWhiteSpace(storeName) || string.IsNullOrWhiteSpace(workKey) || string.IsNullOrWhiteSpace(holderId))
+      return Result.BadRequest("storeName, workKey, and holderId are required.");
+
+    var existing = await stateStore.GetStateAndETagAsync<DaprWorkLease>(storeName, workKey, cancellationToken).ConfigureAwait(false);
+    if (!existing.IsSuccess)
+      return existing.ToResult();
+
+    var (lease, _) = existing.Value;
+    if (lease is null)
+      return Result.Ok();
+
+    if (!string.Equals(lease.HolderId, holderId, StringComparison.Ordinal))
+      return Result.Conflict("Lease is held by another instance.");
+
+    return await stateStore.DeleteStateAsync(storeName, workKey).ConfigureAwait(false);
+  }
+
+  public async Task<Result<DaprWorkLease?>> GetAsync(
+    string storeName,
+    string workKey,
+    CancellationToken cancellationToken = default) {
+    if (string.IsNullOrWhiteSpace(storeName) || string.IsNullOrWhiteSpace(workKey))
+      return Result<DaprWorkLease?>.BadRequest(null, "storeName and workKey are required.");
+
+    var existing = await stateStore.GetStateAndETagAsync<DaprWorkLease>(storeName, workKey, cancellationToken).ConfigureAwait(false);
+    if (!existing.IsSuccess)
+      return existing.ToResult().ToResultOfType<DaprWorkLease?>(null);
+
+    return Result<DaprWorkLease?>.Ok(existing.Value.Value);
+  }
+
+  private static Result Validate(string storeName, string workKey, string holderId, TimeSpan ttl) {
+    if (string.IsNullOrWhiteSpace(storeName) || string.IsNullOrWhiteSpace(workKey) || string.IsNullOrWhiteSpace(holderId))
+      return Result.BadRequest("storeName, workKey, and holderId are required.");
+    if (ttl <= TimeSpan.Zero)
+      return Result.BadRequest("ttl must be positive.");
+    return Result.Ok();
+  }
+}