CTXLog

A context-aware structured logging package for Go that provides a robust wrapper around log/slog with enhanced functionality and configuration options. Under the hood, it uses go.uber.org/zap as the logging backend for optimal performance and reliability.

Package Overview

CTXLog is designed to simplify structured logging in Go applications by providing context-aware logging capabilities with support for both development and production environments. It seamlessly integrates with Go's standard log/slog package while adding powerful features like context propagation, sampling, and OpenTelemetry integration. The package leverages go.uber.org/zap as its logging backend, combining the convenience of slog's interface with Zap's high-performance logging capabilities.

Key Features

• Context-aware logging with automatic context propagation
• Support for both development (human-readable) and production (JSON) logging formats
• Automatic source code location (file and line number) tracking
• Log sampling capabilities for high-throughput applications
• OpenTelemetry integration
• Built-in test logging support
• Error logging with automatic stack traces
• Convenient helper functions for common logging patterns
• Group-based logging for better organization
• High-performance logging through Zap backend

Configuration Options

The logger can be configured using the following options:

Environment Mode

• WithEnvType(): Sets the logger environment mode
  • EnvDevelopment: Human-readable logs for development
  • EnvProduction: JSON logs for production (default)

Log Level and Source

• WithLevel(level slog.Leveler): Sets the minimum logging level
• WithSource(bool): Adds file name and line number to log records

Identification

• WithName(name string): Sets the logger name

Sampling

• WithSampler(tick time.Duration, first, thereafter int): Configures log sampling
  • tick: Sampling interval
  • first: Number of entries to log during the interval
  • thereafter: Number of entries to log after the initial entries

Integration

• WithOtelTracing(): Enables OpenTelemetry integration
• WithTesting(t testing.TB): Configures logger for use in tests

Installation

go get github.com/n-r-w/ctxlog

Usage Examples

See example/main.go for comprehensive usage examples, including:

• Basic logger setup with production mode and debug level
• Context propagation and extraction
• Structured logging with various field types
• Group-based logging
• Error handling with automatic stack traces
• Working with context-bound loggers

The example demonstrates all major features and provides a practical reference for integrating CTXLog into your application.

ILogger Interface

ILogger is a logger interface to extract the logger implementation from the project to external dependencies.

This package contains two implementations of the ctxlog.ILogger interface:

• ctxlog.NewWrapper - allows wrapping ctxlog.Logger in this interface.
• ctxlog.NewStubWrapper - fake logging. It does not do anything.