[codex] Expose structured log storage diagnostics (#7446)

* Expose structured log storage diagnostics

* Address structured log diagnostics review

* Fix checked storage diagnostics aggregation

specs/005-structured-log-persistence/quickstart.md

@@ -46,6 +46,7 @@ Studio continues to use:
 
 - `/diagnostics/structured-logs/recent`
 - `/diagnostics/structured-logs/sources`
+- `/diagnostics/structured-logs/storage`
 - `/elsa/hubs/diagnostics/structured-logs`
 
 ## Migrations

src/modules/Elsa.Diagnostics.StructuredLogs.Persistence.Relational/Contracts/IStructuredLogWriteBuffer.cs

@@ -2,9 +2,7 @@ using Elsa.Diagnostics.StructuredLogs.Contracts;
 
 namespace Elsa.Diagnostics.StructuredLogs.Persistence.Relational.Contracts;
 
-public interface IStructuredLogWriteBuffer : IStructuredLogSink
+public interface IStructuredLogWriteBuffer : IStructuredLogSink, IStructuredLogStorageDiagnostics
 {
-    long DroppedWriteCount { get; }
-
     ValueTask FlushAsync(CancellationToken cancellationToken = default);
 }

src/modules/Elsa.Diagnostics.StructuredLogs.Persistence.Relational/Extensions/RelationalStructuredLogsServiceCollectionExtensions.cs

@@ -23,6 +23,7 @@ public static class RelationalStructuredLogsServiceCollectionExtensions
         services.TryAddSingleton<StructuredLogRetentionService>();
         services.AddSingleton<IStructuredLogStore>(sp => sp.GetRequiredService<StructuredLogWriteBuffer>());
         services.AddSingleton<IStructuredLogWriteBuffer>(sp => sp.GetRequiredService<StructuredLogWriteBuffer>());
+        services.AddSingleton<IStructuredLogStorageDiagnostics>(sp => sp.GetRequiredService<StructuredLogWriteBuffer>());
         services.AddHostedService(sp => sp.GetRequiredService<StructuredLogWriteBuffer>());
 
         return services;

src/modules/Elsa.Diagnostics.StructuredLogs.Persistence.Relational/README.md

@@ -11,3 +11,5 @@ To add a new relational provider such as SQL Server or PostgreSQL:
 5. Register those services and call `AddRelationalStructuredLogPersistence`.
 
 The core `Elsa.Diagnostics.StructuredLogs` package must remain unaware of provider packages. Provider-specific SQL and migration runner dependencies belong in provider packages.
+
+`StructuredLogWriteBuffer` reports dropped durable writes through the core `IStructuredLogStorageDiagnostics` contract. The core endpoint `GET /diagnostics/structured-logs/storage` returns that provider-neutral count for Studio and other diagnostics clients.

src/modules/Elsa.Diagnostics.StructuredLogs/Contracts/IStructuredLogStorageDiagnostics.cs

@@ -0,0 +1,6 @@
+namespace Elsa.Diagnostics.StructuredLogs.Contracts;
+
+public interface IStructuredLogStorageDiagnostics
+{
+    long DroppedWriteCount { get; }
+}

src/modules/Elsa.Diagnostics.StructuredLogs/Endpoints/StructuredLogs/Storage/Endpoint.cs

@@ -0,0 +1,24 @@
+using Elsa.Abstractions;
+using Elsa.Diagnostics.StructuredLogs.Contracts;
+using Elsa.Diagnostics.StructuredLogs.Models;
+using Elsa.Diagnostics.StructuredLogs.Permissions;
+using JetBrains.Annotations;
+
+namespace Elsa.Diagnostics.StructuredLogs.Endpoints.StructuredLogs.Storage;
+
+[PublicAPI]
+internal class Endpoint(IEnumerable<IStructuredLogStorageDiagnostics> storageDiagnostics) : ElsaEndpointWithoutRequest<StructuredLogStorageDiagnostics>
+{
+    public override void Configure()
+    {
+        Get("/diagnostics/structured-logs/storage");
+        ConfigurePermissions(StructuredLogsPermissions.Read);
+    }
+    
+    public override Task<StructuredLogStorageDiagnostics> ExecuteAsync(CancellationToken cancellationToken)
+    {
+        var diagnostics = storageDiagnostics.ToList();
+        var droppedWriteCount = diagnostics.Aggregate(0L, (acc, x) => checked(acc + x.DroppedWriteCount));
+        return Task.FromResult(new StructuredLogStorageDiagnostics(droppedWriteCount, diagnostics.Count > 0));
+    }
+}

src/modules/Elsa.Diagnostics.StructuredLogs/Models/StructuredLogStorageDiagnostics.cs

@@ -0,0 +1,3 @@
+namespace Elsa.Diagnostics.StructuredLogs.Models;
+
+public record StructuredLogStorageDiagnostics(long DroppedWriteCount, bool HasStorageDiagnosticsProvider);

src/modules/Elsa.Diagnostics.StructuredLogs/README.md

@@ -30,7 +30,7 @@ This maps the structured logs hub at `/elsa/hubs/diagnostics/structured-logs` an
 
 ## Authorization
 
-The recent-log endpoint and source-list endpoint require the `read:diagnostics:structured-logs` permission. The SignalR hub requires an authenticated user, matching the existing Elsa workflow hub authorization pattern. Grant `read:diagnostics:structured-logs` only to operators and developers who are allowed to inspect backend logs.
+The recent-log endpoint, source-list endpoint, and storage-diagnostics endpoint require the `read:diagnostics:structured-logs` permission. The SignalR hub requires an authenticated user, matching the existing Elsa workflow hub authorization pattern. Grant `read:diagnostics:structured-logs` only to operators and developers who are allowed to inspect backend logs.
 
 ## Studio Integration
 
@@ -40,6 +40,7 @@ Elsa Studio can use this module to show:
 - Live log events as the server emits them.
 - Level, category, message, tenant, workflow, trace, correlation, source, and time filters.
 - Cluster/source metadata such as source ID, pod name, namespace, container name, node name, machine name, process ID, and source health.
+- Storage pressure metadata such as dropped durable write counts and whether the active store reports storage diagnostics.
 
 ## Clustered Deployments
 
@@ -57,7 +58,7 @@ services.AddElsa(elsa =>
 });
 ```
 
-The core module remains storage-provider neutral. Custom stores can replace `IStructuredLogStore` while live updates continue through `IStructuredLogLiveFeed`; Studio continues to use the same REST and SignalR contracts, including source filtering and source-change notifications.
+The core module remains storage-provider neutral. Custom stores can replace `IStructuredLogStore` while live updates continue through `IStructuredLogLiveFeed`; Studio continues to use the same REST and SignalR contracts, including source filtering, source-change notifications, and storage diagnostics.
 
 ## Redaction