Перевести «не найдено» кандидатов Discovery на исключения

DiscoveryCandidatesService (get/set/status/mark_joined/mark_rejected/add при отсутствии задачи) бросает NotFoundException; skip-ветки add оставлены null. Эндпоинты без локальных 404-проверок.

src/core/Deal.Api/Endpoints/DiscoveryEndpoints.cs

@@ -55,9 +55,6 @@ public static class DiscoveryEndpoints
     // Путь лога задачи (GET).
     private const string TaskLogPath = "/tasks/{task_id}/log";
 
-    // 404: кандидат не найден.
-    private const string CandidateNotFoundDetail = "Кандидат не найден";
-
     private const string AlreadyJoinedDetail = "Уже вступили в этот источник";
 
     private const string JoinedRejectDetail = "Уже вступили — удалите источник из каналов";
@@ -281,11 +278,7 @@ public static class DiscoveryEndpoints
         }
 
         DiscoveryCandidatesService candidates = context.RequestServices.GetRequiredService<DiscoveryCandidatesService>();
-        DiscoveryCandidateDto? row = await candidates.GetAsync(dialog_id, ct);
+        DiscoveryCandidateDto row = await candidates.GetAsync(dialog_id, ct);
-        if (row is null)
-        {
-            return EndpointResults.NotFound(CandidateNotFoundDetail);
-        }
 
         if (row.Status == DiscoveryCandidateStatuses.Joined)
         {
@@ -314,8 +307,8 @@ public static class DiscoveryEndpoints
 
         try
         {
-            DiscoveryCandidateDto? joined = await candidates.MarkJoinedAsync(dialog_id, auto: false, ct);
+            DiscoveryCandidateDto joined = await candidates.MarkJoinedAsync(dialog_id, auto: false, ct);
-            return joined is null ? EndpointResults.NotFound(CandidateNotFoundDetail) : Results.Ok(joined);
+            return Results.Ok(joined);
         }
         catch (DiscoveryValidationException exception)
         {
@@ -334,11 +327,7 @@ public static class DiscoveryEndpoints
         }
 
         DiscoveryCandidatesService candidates = context.RequestServices.GetRequiredService<DiscoveryCandidatesService>();
-        DiscoveryCandidateDto? row = await candidates.GetAsync(dialog_id, ct);
+        DiscoveryCandidateDto row = await candidates.GetAsync(dialog_id, ct);
-        if (row is null)
-        {
-            return EndpointResults.NotFound(CandidateNotFoundDetail);
-        }
 
         if (row.Status == DiscoveryCandidateStatuses.Joined)
         {
@@ -347,8 +336,8 @@ public static class DiscoveryEndpoints
 
         try
         {
-            DiscoveryCandidateDto? rejected = await candidates.MarkRejectedAsync(dialog_id, ManualRejectReason, ct);
+            DiscoveryCandidateDto rejected = await candidates.MarkRejectedAsync(dialog_id, ManualRejectReason, ct);
-            return rejected is null ? EndpointResults.NotFound(CandidateNotFoundDetail) : Results.Ok(rejected);
+            return Results.Ok(rejected);
         }
         catch (DiscoveryValidationException exception)
         {

src/core/Deal.Modules.Discovery/Application/Services/DiscoveryCandidatesService.cs

@@ -2,6 +2,7 @@ using Deal.Contracts.Integrations.Models;
 using Deal.Modules.Discovery.Application.Abstractions;
 using Deal.Modules.Discovery.Application.Exceptions;
 using Deal.Modules.Discovery.Application.Models;
+using Deal.SharedKernel.Errors;
 
 namespace Deal.Modules.Discovery.Application.Services;
 
@@ -13,6 +14,10 @@ public sealed class DiscoveryCandidatesService(
     DiscoveryLogService log,
     DiscoveryBlacklistService blacklist)
 {
+    private const string CandidateEntityName = "Кандидат";
+
+    private const string TaskEntityName = "Задача поиска";
+
     /// <summary>
     /// 400 mark_rejected
     /// </summary>
@@ -53,10 +58,12 @@ public sealed class DiscoveryCandidatesService(
     /// Кандидат по dialog_id.
     /// </summary>
     /// <param name="dialogId">Подписанный id источника.</param>
-    /// <returns>Кандидат или null (404 «Кандидат не найден»).</returns>
+    /// <returns>Кандидат.</returns>
-    public Task<DiscoveryCandidateDto?> GetAsync(string dialogId, CancellationToken ct)
+    /// <exception cref="NotFoundException">Кандидат не найден.</exception>
+    public async Task<DiscoveryCandidateDto> GetAsync(string dialogId, CancellationToken ct)
     {
-        return store.GetCandidateAsync(dialogId, ct);
+        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
     }
 
     /// <summary>
@@ -78,11 +85,8 @@ public sealed class DiscoveryCandidatesService(
         string hue,
         CancellationToken ct)
     {
-        DiscoveryTaskDto? task = await store.GetTaskAsync(taskId, ct).ConfigureAwait(false);
+        DiscoveryTaskDto task = await store.GetTaskAsync(taskId, ct).ConfigureAwait(false)
-        if (task is null)
+            ?? throw new NotFoundException(TaskEntityName, taskId);
-        {
-            return null;
-        }
 
         if (await store.IsDialogMonitoredAsync(dialogId, ct).ConfigureAwait(false))
         {
@@ -125,7 +129,8 @@ public sealed class DiscoveryCandidatesService(
         };
         await store.CreateCandidateAsync(row, ct).ConfigureAwait(false);
         await store.BumpTaskCounterAsync(taskId, DiscoveryCounterField.Found, 1, ct).ConfigureAwait(false);
-        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
     }
 
     /// <summary>
@@ -134,18 +139,21 @@ public sealed class DiscoveryCandidatesService(
     /// <param name="taskId">Id задачи.</param>
     /// <param name="dialogId">Подписанный id источника.</param>
     /// <param name="patch">Изменяемые поля (null — не менять).</param>
-    /// <returns>Обновлённый кандидат либо null — задачи/кандидата нет (или кандидат другой задачи).</returns>
+    /// <returns>Обновлённый кандидат.</returns>
-    public async Task<DiscoveryCandidateDto?> SetAsync(
+    /// <exception cref="NotFoundException">Задача или кандидат не найдены.</exception>
+    public async Task<DiscoveryCandidateDto> SetAsync(
         string taskId,
         string dialogId,
         DiscoveryCandidatePatch patch,
         CancellationToken ct)
     {
-        DiscoveryTaskDto? task = await store.GetTaskAsync(taskId, ct).ConfigureAwait(false);
+        _ = await store.GetTaskAsync(taskId, ct).ConfigureAwait(false)
-        DiscoveryCandidateDto? current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+            ?? throw new NotFoundException(TaskEntityName, taskId);
-        if (task is null || current is null || current.TaskId != taskId)
+        DiscoveryCandidateDto current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
+        if (current.TaskId != taskId)
         {
-            return null;
+            throw new NotFoundException(CandidateEntityName, dialogId);
         }
 
         DiscoveryCandidatePatch normalized = NormalizePatch(patch, current);
@@ -159,7 +167,8 @@ public sealed class DiscoveryCandidatesService(
         }
 
         await store.PatchCandidateAsync(dialogId, normalized, ct).ConfigureAwait(false);
-        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
     }
 
     /// <summary>
@@ -167,9 +176,10 @@ public sealed class DiscoveryCandidatesService(
     /// </summary>
     /// <param name="dialogId">Подписанный id источника.</param>
     /// <param name="status">Новый статус: new|review.</param>
-    /// <returns>Обновлённый кандидат либо null (кандидата нет).</returns>
+    /// <returns>Обновлённый кандидат.</returns>
+    /// <exception cref="NotFoundException">Кандидат не найден.</exception>
     /// <exception cref="DiscoveryValidationException">Статус не new/review.</exception>
-    public async Task<DiscoveryCandidateDto?> SetStatusAsync(
+    public async Task<DiscoveryCandidateDto> SetStatusAsync(
         string dialogId,
         string status,
         CancellationToken ct)
@@ -179,11 +189,8 @@ public sealed class DiscoveryCandidatesService(
             throw new DiscoveryValidationException(string.Format(TransitionNotAllowedFormat, status));
         }
 
-        DiscoveryCandidateDto? current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        DiscoveryCandidateDto current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
-        if (current is null)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
-        {
-            return null;
-        }
 
         await store.SetCandidateStatusAsync(dialogId, status, ct).ConfigureAwait(false);
         if (status == DiscoveryCandidateStatuses.Review)
@@ -195,7 +202,8 @@ public sealed class DiscoveryCandidatesService(
                 ct).ConfigureAwait(false);
         }
 
-        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
     }
 
     /// <summary>
@@ -203,17 +211,15 @@ public sealed class DiscoveryCandidatesService(
     /// </summary>
     /// <param name="dialogId">Подписанный id источника.</param>
     /// <param name="auto">True — авто-вступление воркера; false — ручное.</param>
-    /// <returns>Кандидат в joined либо null (кандидата нет). Повторный вызов для joined — идемпотентен.</returns>
+    /// <returns>Кандидат в joined. Повторный вызов для joined — идемпотентен.</returns>
-    public async Task<DiscoveryCandidateDto?> MarkJoinedAsync(
+    /// <exception cref="NotFoundException">Кандидат не найден.</exception>
+    public async Task<DiscoveryCandidateDto> MarkJoinedAsync(
         string dialogId,
         bool auto,
         CancellationToken ct)
     {
-        DiscoveryCandidateDto? current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        DiscoveryCandidateDto current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
-        if (current is null)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
-        {
-            return null;
-        }
 
         if (current.Status == DiscoveryCandidateStatuses.Joined)
         {
@@ -224,7 +230,8 @@ public sealed class DiscoveryCandidatesService(
         await store.BumpTaskCounterAsync(current.TaskId, DiscoveryCounterField.Joined, 1, ct).ConfigureAwait(false);
         string logEvent = auto ? DiscoveryLogEvents.JoinAuto : DiscoveryLogEvents.JoinManual;
         await log.AddAsync(current.TaskId, logEvent, string.Format(JoinedLogFormat, dialogId), ct).ConfigureAwait(false);
-        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
     }
 
     /// <summary>
@@ -232,18 +239,16 @@ public sealed class DiscoveryCandidatesService(
     /// </summary>
     /// <param name="dialogId">Подписанный id источника.</param>
     /// <param name="reason">Причина отклонения (в лог/чёрный список; «отклонено вручную» — эндпоинт reject).</param>
-    /// <returns>Кандидат в rejected либо null (кандидата нет). Повторный вызов для rejected — идемпотентен.</returns>
+    /// <returns>Кандидат в rejected. Повторный вызов для rejected — идемпотентен.</returns>
+    /// <exception cref="NotFoundException">Кандидат не найден.</exception>
     /// <exception cref="DiscoveryValidationException">Источник уже joined — отклонить нельзя.</exception>
-    public async Task<DiscoveryCandidateDto?> MarkRejectedAsync(
+    public async Task<DiscoveryCandidateDto> MarkRejectedAsync(
         string dialogId,
         string reason,
         CancellationToken ct)
     {
-        DiscoveryCandidateDto? current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        DiscoveryCandidateDto current = await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
-        if (current is null)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
-        {
-            return null;
-        }
 
         if (current.Status == DiscoveryCandidateStatuses.Joined)
         {
@@ -260,7 +265,8 @@ public sealed class DiscoveryCandidatesService(
         string text = string.IsNullOrEmpty(reason) ? string.Format(RejectedLogFormat, dialogId) : reason;
         await log.AddAsync(current.TaskId, DiscoveryLogEvents.Reject, text, ct).ConfigureAwait(false);
         await blacklist.AddAsync(dialogId, current.Name, reason ?? string.Empty, ct).ConfigureAwait(false);
-        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false);
+        return await store.GetCandidateAsync(dialogId, ct).ConfigureAwait(false)
+            ?? throw new NotFoundException(CandidateEntityName, dialogId);
     }
 
     /// <summary>

src/core/tests/Deal.Tests.Unit/Modules/Discovery/DiscoveryCandidatesServiceTests.cs

@@ -1,7 +1,8 @@
 using Deal.Modules.Discovery.Application.Exceptions;
 using Deal.Modules.Discovery.Application.Models;
-using Deal.Tests.Unit.Support;
 using Deal.Modules.Discovery.Application.Services;
+using Deal.SharedKernel.Errors;
+using Deal.Tests.Unit.Support;
 
 namespace Deal.Tests.Unit.Modules.Discovery;
 
@@ -114,14 +115,13 @@ public sealed class DiscoveryCandidatesServiceTests
     }
 
     [Fact]
-    public async Task Add_MissingTask_ReturnsNullWithoutLog()
+    public async Task Add_MissingTask_ThrowsNotFoundWithoutLog()
     {
         (DiscoveryCandidatesService service, TestDiscoveryStore store) = Create();
 
-        DiscoveryCandidateDto? candidate = await service.AddAsync(
+        await Assert.ThrowsAsync<NotFoundException>(() => service.AddAsync(
-            "dt_missing", "-1001", "Канал", "", DiscoveryCandidateKinds.Channel, "", CancellationToken.None);
+            "dt_missing", "-1001", "Канал", "", DiscoveryCandidateKinds.Channel, "", CancellationToken.None));
 
-        Assert.Null(candidate);
         Assert.Empty(store.Candidates);
         Assert.Empty(store.Log);
     }
@@ -175,13 +175,12 @@ public sealed class DiscoveryCandidatesServiceTests
     }
 
     [Fact]
-    public async Task MarkJoined_MissingCandidate_ReturnsNull()
+    public async Task MarkJoined_MissingCandidate_ThrowsNotFound()
     {
         (DiscoveryCandidatesService service, _) = Create();
 
-        DiscoveryCandidateDto? candidate = await service.MarkJoinedAsync("-1001", auto: true, CancellationToken.None);
+        await Assert.ThrowsAsync<NotFoundException>(
-
+            () => service.MarkJoinedAsync("-1001", auto: true, CancellationToken.None));
-        Assert.Null(candidate);
     }
 
     [Fact]
@@ -238,14 +237,12 @@ public sealed class DiscoveryCandidatesServiceTests
     }
 
     [Fact]
-    public async Task MarkRejected_MissingCandidate_ReturnsNull()
+    public async Task MarkRejected_MissingCandidate_ThrowsNotFound()
     {
         (DiscoveryCandidatesService service, _) = Create();
 
-        DiscoveryCandidateDto? candidate = await service.MarkRejectedAsync(
+        await Assert.ThrowsAsync<NotFoundException>(
-            "-1001", "причина", CancellationToken.None);
+            () => service.MarkRejectedAsync("-1001", "причина", CancellationToken.None));
-
-        Assert.Null(candidate);
     }
 
     [Fact]
@@ -315,17 +312,15 @@ public sealed class DiscoveryCandidatesServiceTests
     }
 
     [Fact]
-    public async Task Set_WrongTask_ReturnsNull()
+    public async Task Set_WrongTask_ThrowsNotFound()
     {
         (DiscoveryCandidatesService service, TestDiscoveryStore store) = Create();
         store.SeedTask(Task("dt_1"));
         store.SeedTask(Task("dt_2"));
         store.SeedCandidate(Candidate("-1001", "dt_1"));
 
-        DiscoveryCandidateDto? candidate = await service.SetAsync(
+        await Assert.ThrowsAsync<NotFoundException>(() => service.SetAsync(
-            "dt_2", "-1001", new DiscoveryCandidatePatch { Participants = 10 }, CancellationToken.None);
+            "dt_2", "-1001", new DiscoveryCandidatePatch { Participants = 10 }, CancellationToken.None));
-
-        Assert.Null(candidate); // кандидат другой задачи (python L465–466)
     }
 
     [Fact]