Questions
12 of 29
1How do you make a custom pipe configurable by accepting constructor options in NestJS?
2How do you validate arrays and conditional fields with class-validator in NestJS?
3What is the @ValidateNested() decorator and when must you pair it with @Type()?
4What is the difference between a transformation pipe and a validation pipe in NestJS?
5How do you write a custom pipe for parsing and validating a MongoDB ObjectId param in NestJS?
6How do you write a pipe that uses metatype to skip validation for primitive types the same way ValidationPipe does?
7What are the two ways to register a global pipe in NestJS and what is the difference?
8How does ValidationPipe work with class-validator and class-transformer in NestJS?
9How do you write a custom class-validator decorator in NestJS?
10How do you customise the error response format produced by ValidationPipe in NestJS?
11How do you write an async custom validator that checks uniqueness against a database in NestJS?
12What interface must a custom pipe implement and what does the transform() method receive?
13What are all the significant ValidationPipe options and what does each do in NestJS?
14How do you write a pipe that validates and parses a date string from a route parameter in NestJS?
15What is a pipe in NestJS and what are its two primary uses?
16What is class-transformer and how does it complement class-validator in NestJS?
17What does the @Transform() decorator do in class-transformer and when should you use it?
18How does @Type() interact with discriminated unions and polymorphic DTOs in class-transformer?
19What is class-validator and how does it integrate with NestJS ValidationPipe?
20How do you unit test a custom pipe in NestJS?
21What does @Exclude() and @Expose() do and how do you use them to strip sensitive fields from responses?
22What are all the built-in pipes NestJS ships with?
23What is the excludeExtraneousValues option in class-transformer and how does it differ from whitelist in ValidationPipe?
24How do you handle file upload validation with ParseFilePipe and custom file validators in NestJS?
25How do you write a custom pipe that sanitizes a string input (trim and lowercase) in NestJS?
26How do you pass options to a built-in pipe like ParseIntPipe or ParseUUIDPipe in NestJS?
27What is the difference between applying a pipe at the param level vs handler level vs globally in NestJS?
28Can a pipe be asynchronous in NestJS and how do you implement one?
29How do you use validation groups with class-validator to apply different rules for create vs update operations in NestJS?
