SimplyWorks.Logger.ElasticSearch 10.0.3

SW-Logger

Package	Version	Downloads
SimplyWorks.Logger.ElasticSearch
SimplyWorks.Logger.Console

Overview

SW-Logger is a .NET logging library built on top of Serilog that provides structured logging capabilities for .NET 8.0 applications. It offers two main logging sinks:

• Console Logger: Provides enhanced console logging with structured output and request context enrichment
• ElasticSearch Logger: Enables logging to ElasticSearch with data streams, lifecycle policies, and correlation tracking

Features

• 🎯 Structured Logging: Built on Serilog for structured, searchable logs
• 🔍 Request Context Enrichment: Automatically enriches logs with correlation IDs and user information
• 🗂️ ElasticSearch Integration: Direct logging to ElasticSearch with data streams and index lifecycle management
• 📊 Console Logging: Enhanced console output with JSON formatting in production
• ⚙️ Configuration-Driven: Flexible configuration through appsettings.json
• 🔄 Request Logging: Built-in HTTP request/response logging
• 🏷️ Environment Support: Environment-specific logging configurations

Installation

Console Logger

dotnet add package SimplyWorks.Logger.Console

ElasticSearch Logger

dotnet add package SimplyWorks.Logger.ElasticSearch

Quick Start

Console Logger Setup

1. Configure Services

using SW.Logger.Console;

public void ConfigureServices(IServiceCollection services)
{
    services.AddSWConsoleLogger(options =>
    {
        options.ApplicationName = "MyApp";
        options.LoggingLevel = 2; // Information (the default)
    });
}

2. Configure Application Pipeline

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    app.UseSWConsoleLogger();
    // ... other middleware
}

ElasticSearch Logger Setup

1. Configure Host Builder

using SW.Logger.ElasticSerach;

public static IHostBuilder CreateHostBuilder(string[] args) =>
    Host.CreateDefaultBuilder(args)
        .ConfigureWebHostDefaults(webBuilder =>
        {
            webBuilder.UseStartup<Startup>();
        })
        .UseSwElasticSearchLogger(options =>
        {
            options.ApplicationName = "MyApp";
            options.ElasticsearchUrl = "https://localhost:9200";
        });

To add more Serilog sinks or enrichers, pass configureLogger; it runs after the built-in ones. Serilog replaces the .NET logging pipeline, so a logging provider such as Sentry's never receives these logs unless it is added here as a Serilog sink:

builder.Host.UseSwElasticSearchLogger(configureLogger: (context, loggerConfiguration) =>
    loggerConfiguration.WriteTo.Sentry(o =>
    {
        o.InitializeSdk = false; // already initialized by UseSentry
        o.MinimumEventLevel = LogEventLevel.Error;
    }));

2. Configure Application Pipeline

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    app.UseRequestContextLogEnricher();
    // ... other middleware
}

Configuration

appsettings.json Configuration

{
  "SwLogger": {
    "ApplicationName": "MyApplication",
    "LoggingLevel": 2,
    "ElasticsearchUrl": "https://localhost:9200",
    "ElasticsearchUser": "elastic",
    "ElasticsearchPassword": "password",
    "ElasticsearchEnvironments": "Development,Staging,Production",
    "ElasticsearchCertificatePath": "/path/to/certificate.crt",
    "ElasticsearchDeleteIndexAfterDays": 90
  }
}

Configuration Options

Console Logger Options

• ApplicationName: Name of your application (default: "unknownapp")
• ApplicationVersion: Version of your application (auto-detected from assembly)
• LoggingLevel: Minimum level as Serilog's LogEventLevel number: 0=Verbose, 1=Debug, 2=Information (default), 3=Warning, 4=Error, 5=Fatal. Microsoft.AspNetCore and Microsoft.EntityFrameworkCore are always held at Warning.
• Environments: Comma-separated list of environments where logging is active
• LogRequests: Write one line per HTTP request with its duration, status and a Route property holding the route template (/api/orders/{id}), so requests can be grouped per endpoint, plus User (the caller's name identifier, when signed in) and UserAgent (cut to 200 characters), so requests can be counted per caller. Kept even when LoggingLevel is above Information. Default true.
• SlowQueryMilliseconds: EF Core commands taking at least this long are logged ("Executed DbCommand (Nms)"), so a slow request can be traced to its query; faster ones are not logged. Failed commands always are. 0 disables. Default 500.
• Properties: added to every log line, such as which deployment wrote it. Set in code (o.Properties["Deployment"] = "acme") or under SwLogger:Properties; configuration wins for the same name. Environment, Application and ApplicationVersion keep the logger's values, and an empty value is left out.
• QuietRequestPaths: Comma-separated path prefixes whose successful requests are dropped (default /health,/healthz,/metrics). Failures are still logged.

Upgrading: before this change LoggingLevel defaulted to 1, which is Debug, not Information as this README claimed. Apps that never set it now log at Information, and framework chatter from ASP.NET Core and EF Core is Warning-only.

ElasticSearch Logger Options

• ApplicationName: Name of your application (used for index naming)
• ApplicationVersion: Version of your application
• LoggingLevel: Serilog logging level
• ElasticsearchUrl: ElasticSearch cluster URL
• ElasticsearchUser: ElasticSearch username
• ElasticsearchPassword: ElasticSearch password
• ElasticsearchEnvironments: Environments where ElasticSearch logging is enabled
• ElasticsearchCertificatePath: Path to SSL certificate (optional)
• ElasticsearchDeleteIndexAfterDays: Days logs are kept before being deleted (default: 90). Set to 0 to keep logs forever.
• ElasticsearchReplicasAfterRollover: Replica count for each monthly backing index once it has rolled over and is no longer written to. 0 halves the disk older logs use; the index currently being written keeps its replicas, so node restarts never stop logging. Not set by default (replicas unchanged).
• MinimumLevelOverrides: Minimum level per log source, overriding LoggingLevel for that source and everything under it. Levels are Serilog's: 0 Verbose, 1 Debug, 2 Information, 3 Warning, 4 Error, 5 Fatal. For example, to stop shipping one line per database query:

  "MinimumLevelOverrides": { "Microsoft.EntityFrameworkCore": 3, "Microsoft.AspNetCore": 3 }
  

Usage Examples

Basic Logging

using Microsoft.Extensions.Logging;

public class HomeController : ControllerBase
{
    private readonly ILogger<HomeController> _logger;

    public HomeController(ILogger<HomeController> logger)
    {
        _logger = logger;
    }

    public IActionResult Get()
    {
        _logger.LogInformation("Processing GET request for Home");
        
        try
        {
            // Your logic here
            return Ok();
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error processing GET request");
            throw;
        }
    }
}

Structured Logging with Context

_logger.LogInformation("User {UserId} accessed resource {ResourceId}", 
    userId, resourceId);

_logger.LogWarning("Failed login attempt for {Username} from {IpAddress}", 
    username, ipAddress);

Project Structure

SW-Logger/
├── SW.Logger.Console/           # Console logging package
│   ├── IAppBuilderExtensions.cs
│   ├── IServiceCollectionExtensions.cs
│   └── LoggerOptions.cs
├── SW.Logger.ElasticSearch/     # ElasticSearch logging package
│   ├── IAppBuilderExtensions.cs
│   ├── IHostBuilderExtensions.cs
│   ├── LoggerOptions.cs
│   └── StringExtensions.cs
└── SW.Logger.SampleWeb/         # Sample web application
    ├── Program.cs
    ├── Startup.cs
    └── appsettings.json

ElasticSearch Features

Data Streams

The ElasticSearch logger uses data streams with the naming pattern: logs-{application-name}-{environment}

Index Lifecycle Management

On startup, and every 24 hours after, the logger creates an ILM policy named logs-{application-name}-{environment}-retention and applies it to its data stream. The policy rolls the data stream over monthly (or at 50 GB per shard) and deletes data ElasticsearchDeleteIndexAfterDays after rollover. Because it's applied to the data stream itself rather than through an index template, it isn't affected by which index template wins for the stream.

Authentication

Supports both basic authentication and certificate-based authentication for ElasticSearch clusters.

Dependencies

Console Logger

• Serilog.AspNetCore (8.0.3)
• SimplyWorks.PrimitiveTypes (8.0.0)

ElasticSearch Logger

• Elastic.Serilog.Sinks (8.18.2)
• NEST (7.17.5)
• Serilog.AspNetCore (8.0.3)
• SimplyWorks.PrimitiveTypes (8.0.0)

Requirements

• .NET 8.0 or higher
• For ElasticSearch logging: ElasticSearch cluster (7.x or 8.x)

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

If you encounter any bugs or have feature requests, please submit an issue on GitHub.