ln-771-logging-configurator

| Aspect | Details |

|--------|---------|

| Input | Context Store from ln-770 |

| Output | Logging configuration files |

| Stacks | .NET (Serilog), Python (structlog) |

---

Accept Context Store from coordinator.

Required Context:

• STACK: .NET or Python
• FRAMEWORK: ASP.NET Core or FastAPI
• FRAMEWORK_VERSION: Version number
• PROJECT_ROOT: Project directory path
• ENVIRONMENT: Development or Production

Validation:

• If STACK not provided, detect from project files
• If version not provided, use latest stable

---

Use MCP tools to get up-to-date documentation.

For .NET (Serilog):

```

MCP ref: "Serilog ASP.NET Core structured logging configuration"

Context7: /serilog/serilog-aspnetcore

```

For Python (structlog):

```

MCP ref: "structlog Python structured logging configuration"

Context7: /hynek/structlog

```

Key Patterns to Research:

1. Request logging middleware
2. Log enrichment (correlation ID, user context)
3. Log level configuration by environment
4. Sink configuration (Console, File, Seq, Elastic)

---

Ask user for configuration preferences.

Q1: Log Format

| Option | When to Use |

|--------|-------------|

| JSON (Recommended for Production) | Machine-readable, log aggregation systems |

| Pretty/Colored (Recommended for Development) | Human-readable, local debugging |

Q2: Enrichment Fields

| Field | Description | Default |

|-------|-------------|---------|

| correlationId | Request tracking across services | ✓ Yes |

| userId | Authenticated user identifier | ✓ Yes |

| requestPath | HTTP request path | ✓ Yes |

| responseTime | Request duration in ms | ✓ Yes |

| machineName | Server hostname | Optional |

| threadId | Thread identifier | Optional |

Q3: Log Sinks

| Sink | Use Case |

|------|----------|

| Console | Always enabled |

| File | Local persistence, log rotation |

| Seq | Structured log server |

| Elasticsearch | Log aggregation at scale |

Q4: Log Levels by Environment

| Level | Development | Production |

|-------|-------------|------------|

| Default | Debug | Information |

| Microsoft.* | Information | Warning |

| System.* | Information | Warning |

| Application | Debug | Information |

---

Generate files based on stack and decisions.

.NET Output Files

| File | Purpose |

|------|---------|

| Extensions/LoggingExtensions.cs | Service registration |

| appsettings.json (update) | Serilog configuration |

| appsettings.Development.json (update) | Dev overrides |

Generation Process:

1. Use MCP ref to get current Serilog API
2. Generate LoggingExtensions.cs with:

- UseSerilog configuration

- Request logging middleware

- Enrichment configuration

1. Update appsettings.json with Serilog section

Packages to Add:

• Serilog.AspNetCore
• Serilog.Sinks.Console
• Serilog.Sinks.File (if File sink selected)
• Serilog.Enrichers.Environment (if machineName selected)

Python Output Files

| File | Purpose |

|------|---------|

| core/logging_config.py | structlog configuration |

| middleware/logging_middleware.py | Request logging |

Generation Process:

1. Use MCP ref to get current structlog API
2. Generate logging_config.py with:

- Processor chain configuration

- Renderer selection (JSON/Console)

- Log level configuration

1. Generate logging_middleware.py for FastAPI

Packages to Add:

• structlog
• python-json-logger (if JSON format)

---

Verify the configuration works.

Validation Steps:

1. Check imports: Ensure all packages are available

- .NET: dotnet list package | grep Serilog

- Python: pip list | grep structlog

1. Syntax check:

- .NET: dotnet build --no-restore

- Python: python -m py_compile core/logging_config.py

1. Test log output:

- Start application

- Make test request

- Verify log format matches configuration

Expected Log Format:

```json

{

"timestamp": "2026-01-10T12:00:00.000Z",

"level": "info",

"message": "Request completed",

"correlationId": "abc-123",

"requestPath": "/api/health",

"responseTime": 45,

"statusCode": 200

}

```

---

Return result to ln-770:

```json

{

"status": "success",

"files_created": [

"Extensions/LoggingExtensions.cs",

"appsettings.json"

],

"packages_added": [

"Serilog.AspNetCore",

"Serilog.Sinks.Console"

],

"registration_code": "services.AddLoggingServices(configuration);",

"message": "Configured structured logging with Serilog"

}

```

---

This skill is idempotent:

• Phase 1: Check if logging already configured (Grep for Serilog/structlog)
• If configured: Return { "status": "skipped", "message": "Logging already configured" }
• If not: Proceed with configuration

---

• [Serilog.AspNetCore](https://github.com/serilog/serilog-aspnetcore)
• [structlog Documentation](https://www.structlog.org/)
• [ASP.NET Core Logging](https://learn.microsoft.com/aspnet/core/fundamentals/logging/)

---

Version: 2.0.0

Last Updated: 2026-01-10