logging-observability-skill

What I do

I help you implement comprehensive logging and observability:

1. Structured Logging: JSON logging with Winston, pino, and structlog
2. OpenTelemetry: Distributed tracing and metrics instrumentation
3. Error Monitoring: Sentry integration patterns for error tracking
4. Correlation IDs: Request tracing across services
5. Log Levels: Proper level usage and filtering strategies
6. Observability Stack: Setup guidance for ELK, Grafana, Jaeger

When to use me

Use this skill when:

• Setting up structured logging in a new project
• Integrating OpenTelemetry for distributed tracing
• Configuring Sentry for error monitoring
• Implementing correlation IDs for request tracing
• Designing log aggregation architecture
• Choosing between logging libraries (Winston vs pino, structlog vs logging)
• Setting up log levels and filtering
• Creating observability dashboards and alerts

Related Skills

• error-resolver-workflow-skill: Handles runtime error diagnosis. This skill handles instrumentation setup (Sentry integration, structured logging configuration). Error-resolver consumes the data this skill produces.
• docker-containerization-skill: Container log driver configuration.
• performance-optimization-skill: Uses tracing data for performance analysis.

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Step 1: Structured Logging

Node.js (pino - Recommended for performance)

import pino from "pino"

const logger = pino({
  level: process.env.LOG_LEVEL || "info",
  transport:
    process.env.NODE_ENV === "development"
      ? { target: "pino-pretty", options: { colorize: true } }
      : undefined,
  formatters: {
    level: (label) => ({ level: label }),
  },
  defaultMeta: {
    service: "my-api",
    version: process.env.APP_VERSION || "1.0.0",
  },
})

export default logger

Node.js (Winston - More configurable)

import winston from "winston"

const logger = winston.createLogger({
  level: process.env.LOG_LEVEL || "info",
  format: winston.format.combine(
    winston.format.timestamp(),
    winston.format.errors({ stack: true }),
    winston.format.json()
  ),
  defaultMeta: { service: "my-api" },
  transports: [
    new winston.transports.Console(),
    new winston.transports.File({ filename: "logs/error.log", level: "error" }),
  ],
})

if (process.env.NODE_ENV !== "production") {
  logger.add(
    new winston.transports.Console({
      format: winston.format.combine(winston.format.colorize(), winston.format.simple()),
    })
  )
}