Task 78 — IHttpClientFactory adoption and standard resilience handlers

Phase: 5 Initiative: 45 Status: done Owner: — Slug: httpclient-factory-adoption

Goal

HttpClient создаётся per-call в 8 местах → socket exhaustion под нагрузкой (TIME_WAIT linger). Дополнительно long-lived new HttpClient хранится в singleton-полях без DNS refresh. Mesh layer уже использует IHttpClientFactory правильно (MeshServiceExtensions.cs:112,173,349), но CLI Program.cs не регистрирует AddHttpClient для tools/detection. Нет Polly resilience handlers на HttpClient-level (AddStandardResilienceHandler).

Точки исправления:

• Per-call new HttpClient: DegradationManager.cs:215, LMStudioClient.cs:54, ProviderHealthChecker.cs:73,123,173, ProviderCapabilityDetector.cs:67,129
• Long-lived new HttpClient в полях: HttpTool.cs:30, A2AClient.cs:27, HttpTransportAdapter.cs:41, GrpcTransportAdapter.cs:61, IntentTransport.cs:25, NetworkMonitor.cs:31, OperatorNotificationService.cs:25, SkillMarketplace.cs:245

Acceptance criteria

Sub-tasks

• Program.cs (CLI) — добавить services.AddHttpClient(); (default factory) если ещё нет.
• Конвертировать per-call new HttpClient → inject IHttpClientFactory через DI: DegradationManager (ping google.com удалён, теперь Degraded если NetworkMonitor не зарегистрирован), LMStudioClient, ProviderHealthChecker, ProviderCapabilityDetector.
• Конвертировать long-lived new HttpClient в полях → inject IHttpClientFactory + CreateClient("Named") per-call: HttpTool, A2AClient, HttpTransportAdapter (legacy ctor через factory), NetworkMonitor, OperatorNotificationService, SkillMarketplace.
• IntentTransport — оставлен legacy new HttpClient ctor для CLI-режима; добавлен HttpClientName const + AddHttpClient<IntentTransport> в MeshServiceExtensions.cs:173 уже использует named-client pattern.
• DegradationManager.cs:215 — убрал hardcoded ping google.com; без зарегистрированного NetworkMonitor помечает network как Degraded (cannot probe) вместо синтетического ping.
• Named clients: llm-health (5s timeout), llm-capabilities (8s), lm-studio-info (5s), network-monitor (config), intent-transport/http-transport (mesh timeout + resilience), grpc-transport, http-tool (HttpConfig timeout + resilience), a2a-client (A2AConfig timeout + resilience), operator-notify (10s + resilience), skill-marketplace (2 min).
• Standard resilience handlers (AddStandardResilienceHandler) на named clients: intent-transport (full: retry + CB + timeout), http-transport (retry + timeout), http-tool (retry + timeout), a2a-client (retry + timeout), operator-notify (soft retry). Health/probe клиенты (llm-health, llm-capabilities, lm-studio-info, network-monitor, grpc-transport, skill-marketplace) — без resilience, best-effort.
• Hercules.csproj — добавлен Microsoft.Extensions.Http.Resilience 10.0.0.
• Конфигурация resilience через appsettings.json: новая секция Http.Resilience (TimeoutSeconds, RetryCount, RetryBaseDelayMs, CircuitBreakerFailureRatio, CircuitBreakerSamplingDurationSeconds, CircuitBreakerMinimumThroughput, CircuitBreakerBreakDurationSeconds).
• GrpcTransportAdapter.cs — HttpClientName = "grpc-transport" const + HttpClient managed by factory when DI-wired. CLI legacy ctor создаёт собственный SocketsHttpHandler + HttpClient (gRPC-специфика: EnableMultipleHttp2Connections).
• Unit-тест tests/Hercules.Agent.Tests/Http/HttpClientFactoryTests.cs — 13 тестов: HttpTool/A2AClient/NetworkMonitor/OperatorNotificationService/ProviderHealthChecker constructor with and without factory, named-client usage через mock factory, allow-list всё ещё работает, NamedClientNames_AreUnique (11 уникальных имён), resilience handler retry на 503 (2 attempts, 200 OK).
• dotnet build + dotnet test pass.

Scope / Likely files

src/agent/Program.cs, src/agent/Hercules.WebApi/Program.cs, src/agent/Degradation/DegradationManager.cs, src/agent/LLM/Providers/LMStudioClient.cs, src/agent/LLM/ProviderHealthChecker.cs, src/agent/LLM/ProviderCapabilityDetector.cs, src/agent/LLM/LlmClientFactory.cs, src/agent/Tools/HttpTool.cs, src/agent/Tools/A2AClient.cs, src/agent/Mesh/Transport/HttpTransportAdapter.cs, src/agent/Mesh/Transport/GrpcTransportAdapter.cs, src/agent/Mesh/IntentTransport.cs, src/agent/Offline/NetworkMonitor.cs, src/agent/Degradation/OperatorNotificationService.cs, src/agent/Skills/SkillMarketplace.cs, src/agent/Config/AppConfig.cs, src/agent/Hercules.csproj, src/agent/appsettings.json, tests/Hercules.Agent.Tests/Http/HttpClientFactoryTests.cs (new)

Dependencies

• блокирует / опирается на: task_024 — tool-registry
• блокирует / опирается на: task_033 — a2a-agent-card
• блокирует / опирается на: task_061 — local-degradation

Risks / Rollback

IHttpClientFactory требует DI — CLI Program.cs должен использовать Host builder (уже использует). AddStandardResilienceHandler добавляет latency на retry; настроить timeout чтобы не превышать deadline. Rollback: вернуть new HttpClient (но socket exhaustion останется).

Implementation notes

src/agent/Hercules.csproj — добавлен Microsoft.Extensions.Http.Resilience 10.0.0.

src/agent/Config/AppConfig.cs — добавлена HttpResilienceConfig (TimeoutSeconds, RetryCount, RetryBaseDelayMs, CircuitBreakerFailureRatio/SamplingDuration/MinimumThroughput/BreakDuration) + property HttpConfig.Resilience со default = new HttpResilienceConfig().

src/agent/appsettings.json — добавлена секция Http.Resilience с дефолтами (TimeoutSeconds=30, RetryCount=3, CircuitBreakerFailureRatio=0.5 и т.д.).

Named-client constants (все уникальные, проверяется тестом NamedClientNames_AreUnique):

• HttpTool.HttpClientName = "http-tool"
• A2AClient.HttpClientName = "a2a-client"
• NetworkMonitor.HttpClientName = "network-monitor"
• OperatorNotificationService.HttpClientName = "operator-notify"
• ProviderHealthChecker.HttpClientName = "llm-health"
• ProviderCapabilityDetector.HttpClientName = "llm-capabilities"
• LMStudioClient.HttpClientName = "lm-studio-info"
• IntentTransport.HttpClientName = "intent-transport"
• HttpTransportAdapter.HttpClientName = "http-transport"
• GrpcTransportAdapter.HttpClientName = "grpc-transport"
• SkillMarketplace.HttpClientName = "skill-marketplace"

Refactored classes (все используют IHttpClientFactory? + legacy fallback):

• HttpTool — DI ctor (HttpConfig, ILogger<HttpTool>, IHttpClientFactory?), legacy ctor сохранён. Per-call using var client = CreateClient().
• A2AClient — DI ctor (A2AConfig, IHttpClientFactory?), legacy ctor сохранён.
• NetworkMonitor — DI ctor (OfflineSyncConfig, ILogger, IHttpClientFactory), legacy ctor сохранён. _ownedHttp?.Dispose().
• OperatorNotificationService — DI ctor (DegradationConfig, ILogger, IHttpClientFactory), legacy ctor сохранён.
• ProviderHealthChecker — DI ctor (LlmConfig, ILogger?, IHttpClientFactory?), legacy ctor сохранён. Per-method ResolveClient().
• ProviderCapabilityDetector — DI ctor (LlmConfig, ILogger?, ICacheService?, IHttpClientFactory?), legacy ctor сохранён.
• LMStudioClient — DI ctor (OpenAICompatibleConfig, ILogger?, IHttpClientFactory?), legacy ctor сохранён. Прокинут через LlmClientFactory.
• LlmClientFactory — DI ctor (LlmConfig, ICacheService?, IHttpClientFactory?); создаёт LMStudioClient с factory.
• HttpTransportAdapter — DI-friendly (ICapabilityLookup, int, IHttpClientFactory?) legacy ctor, factory-aware.
• IntentTransport, GrpcTransportAdapter — добавлены HttpClientName const-ы (legacy ctors без изменений, gRPC-специфика).
• SkillMarketplace — DI ctor (StorageConfig, SkillPackager, IMarketplaceSigningService?, IHttpClientFactory?). ImportFromUrlAsync использует _httpFactory?.CreateClient(HttpClientName).
• DegradationManager.CheckNetworkHealthAsync — убран hardcoded https://www.google.com ping; теперь если _networkMonitor == null помечает network как Degraded (“cannot probe”) вместо синтетического внешнего запроса.

src/agent/Program.cs (CLI) + src/agent/Hercules.WebApi/Program.cs:

• services.AddHttpClient(); (default factory).
• Регистрации 11 named clients с timeout’ами из config + AddStandardResilienceHandler(...) для inter-agent / tool / operator-notify.
• DI registrations обновлены: HttpTool, A2AClient, NetworkMonitor, OperatorNotificationService, SkillMarketplace, ProviderHealthChecker, ProviderCapabilityDetector принимают IHttpClientFactory (через sp.GetService<IHttpClientFactory>() — optional).

tests/Hercules.Agent.Tests/Http/HttpClientFactoryTests.cs (new, 13 tests):

• HttpTool_WithoutFactory_UsesLegacyClient — constructor без factory.
• HttpTool_WithFactory_UsesNamedClient — mock factory → factory.RequestedNames содержит "http-tool".
• HttpTool_RespectsAllowList_EvenWithFactory — allow-list проверяется до CreateClient.
• A2AClient_WithoutFactory_Constructs / A2AClient_WithFactory_UsesNamedClient_UnknownAgentFailsBeforeCall.
• NetworkMonitor_WithoutFactory_Constructs / NetworkMonitor_WithFactory_UsesNamedClient_AndReports.
• OperatorNotificationService_WithoutFactory_Constructs / OperatorNotificationService_WithFactory_UsesNamedClient_DisabledDoesNotCall.
• ProviderHealthChecker_WithoutFactory_Constructs / ProviderHealthChecker_WithFactory_UsesNamedClient.
• NamedClientNames_AreUnique — 11 уникальных имён.
• HttpClient_WithStandardResilience_RetriesOnTransient503 — mock handler (503 → 200), AddStandardResilienceHandler срабатывает, attempts ∈ [2, 4].

Validation

• dotnet build src/agent/Hercules.csproj — succeeded (0 errors, 15 pre-existing warnings).
• dotnet build src/agent/Hercules.WebApi/Hercules.WebApi.csproj — succeeded (0 errors, 1 pre-existing warning).
• dotnet build tests/Hercules.Agent.Tests/Hercules.Agent.Tests.csproj — succeeded (0 errors).
• dotnet test --filter "FullyQualifiedName~HttpClientFactoryTests" — 13/13 passed.
• dotnet test --filter "FullyQualifiedName~ProviderHealthChecker|FullyQualifiedName~ProviderCapabilityDetector|FullyQualifiedName~LlmClientFactory|FullyQualifiedName~NetworkMonitor|FullyQualifiedName~Offline" — 53/53 passed.
• dotnet test --filter "FullyQualifiedName~HttpTool|FullyQualifiedName~A2A|FullyQualifiedName~Degradation|FullyQualifiedName~SkillMarketplace|FullyQualifiedName~OperatorNotification" — 37/38 passed (1 failure = pre-existing BudgetGuardTests.CheckAndGetDegradationMessage_WhenHardCapViolation_ReturnsMessage — Russian text encoding environmental, не связано с правкой).
• Полный прогон: 1796 passed, 10 failed (все failures pre-existing environmental: NumericValidatorTests, WasmToolTests, BudgetGuardTests, OtelServiceTests, RedisTaskQueueTests — подтверждено в tasks 075/076/077).

Commit

• feat(roadmap): complete task 078 - IHttpClientFactory + standard resilience handlers

Links

• Backlog: ../backlog.md
• Roadmap (EN): ../../ROADMAP-EN.md
• Roadmap (RU): ../../ROADMAP-RU.md