Express Middleware
Write Express middleware for logging, auth checks, validation and error handling.
What you'll learn
- Explain the middleware chain and next()
- Write logging and request ID middleware
- Guard routes with auth middleware
- Handle errors in one place
About this course
You learn how middleware runs and write your own for common tasks. Exercises add logging, request IDs, auth checks, validation and a central error handler to an API.
Course curriculum
4 modules and 12 lessons over 3 weeks. Plan for about 9 learning hours.
01How middleware worksWeek 1 · 3 lessons
- The chain
- next() and next(err)
- Order matters
02Common middlewareWeek 1 · 3 lessons
- Logging
- Request IDs
- CORS
03GuardsWeek 2 · 3 lessons
- Auth checks
- Validation
- Rate limits
04ErrorsWeek 3 · 3 lessons
- Async errors
- Error handler
- Exercise review
Project
Middleware set. Logging, auth, validation and error middleware added to a sample API.
Who this course is for
Express developers who copy middleware without knowing how it works.
Prerequisites
You build Express routes.
What's included
- 120-day course access
- Step-by-step lessons
- Practice files
- Reusable code templates
- A graded final exercise
- A digital completion certificate
Learning format
Self-paced practical course, part of our self-paced courses. Graded final exercise with written feedback.
Access and delivery
- Enrollment is activated within 15 minutes after payment.
- Final exercise feedback is delivered within 2 business days of submission, and the completion certificate is issued within 2 business days after passing the final exercise.
Certificate
You receive a digital completion certificate. Final exercise feedback is delivered within 2 business days of submission, and the completion certificate is issued within 2 business days after passing the final exercise.
Frequently asked questions
When does access start?
Enrollment is activated within 15 minutes after payment.
Is payment taken on this website?
No. After you submit your enrollment request, we reply by email with payment details and enrollment confirmation.
Does this course guarantee a job or income?
No. It is an education and training service and does not include employment, income or placement guarantees.
Can I cancel?
Our Refund and Cancellation Policy lists the terms for self-paced course programs.
