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32 questions for “Express & Middleware”
Found in 1 field. Select a question to see its full answer.
Matching topics
Node.js
Express
&
Middleware
15
Information Technology
32 questions in 2 technologies
#
Question
Technology
Topic
Level
1
What is the difference between application-level, router-level, and route-specific
middleware
in
Express
?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Intermediate
2
What does the
express
.json() and
express
.urlencoded() built-in
middleware
do, and why must it be registered before routes that need to read req.body?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Intermediate
3
What is the purpose of the
express
.static() built-in
middleware
, and how would you use it to serve a folder of static assets?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Beginner
4
What is
middleware
in
Express
, and what is the significance of the order in which
middleware
is registered?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Intermediate
5
What is the purpose of the helmet
middleware
package for an
Express
application, and what specific security headers does it set?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Intermediate
6
What is CORS
middleware
in
Express
, and how does the cors package simplify configuring Cross-Origin Resource Sharing?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Intermediate
7
How do you write custom
Express
middleware
that needs to perform asynchronous work, like checking a value against a database, before calling next()?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Advanced
8
How would you implement request validation
middleware
in
Express
using a schema-validation library like Zod or Joi?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Advanced
9
How would you implement a request-logging
middleware
in
Express
that captures method, path, status code, and response time for every request?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Advanced
10
How would you implement conditional
middleware
in
Express
that only applies to certain requests based on a runtime condition?
Node.js › Express & Middleware
Node.js
Express
&
Middleware
Advanced
Show all 32 questions in Information Technology