Error Monitoring & Observability

Error monitoring and observability are critically important aspects of modern web applications. They allow for the rapid identification, diagnosis, and resolution of issues in production.

This guide covers strategies for error monitoring, observability tools, and best practices to ensure application reliability.

Session replay & error tracking:

import LogRocket from 'logrocket';

LogRocket.init('YOUR_APP_ID');

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import { trace } from '@opentelemetry/api';

const tracer = trace.getTracer('my-app');

const span = tracer.startSpan('operation');

Frequently asked questions

What is error monitoring?

Error monitoring involves tracking and alerting on errors that occur within an application, providing insights into the root cause and impact.

How does session replay help with debugging?

Session replay allows developers to record and re-experience user sessions, providing a visual understanding of how users interact with the application and identify issues that might not be apparent through traditional logging.

What is OpenTelemetry and how does it relate to tracing?

OpenTelemetry is an open-source observability framework that provides tools for collecting telemetry data (traces, metrics, logs) from distributed systems. Tracing specifically focuses on tracking requests as they propagate through a system.

How do I handle unhandled errors in my Express.js application?

You should use an error-handling middleware function like `app.use((err, req, res, next) => { ... });` to catch and log any unhandled errors that occur within your application.

How can I log detailed information about errors using the logger?

You can use `logger.error('Unhandled error', { ... });` to log detailed information about an error, including relevant context and data, which helps in diagnosing the root cause.

What is the purpose of sending error data to a monitoring service?

Sending error data to a monitoring service like Sentry allows you to track error trends, identify patterns, and receive alerts when critical errors occur in production.

How do I capture exceptions using Sentry?

You can use `Sentry.captureException(err, { ... });` to automatically send exception details to your Sentry instance for analysis and alerting.

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