Necessary Typescript class property when executing code

Is there a way to determine if a class property is required in Typescript at runtime?

export class A {
  public readonly ab?: number;
  public readonly ac?: number;
  public readonly ad: number;
  public readonly ae: number;
}

Can emitDecoratorMetadata or experimentalDecorators be used to identify that the properties ad and ae are required?

I am working on a REST API where the object of class A is generated automatically, and I need to validate whether ad and ae are provided when POST data is received.

Thank you for your help!

typescriptrestvalidationmetadata

Answer №1

During compilation, all type checking occurs, without any checks happening at runtime. If you need to verify the validity of a received object, manual verification or the use of a library is required, which can somehow validate the server response.

A recommended option is class-validator, which enables class validation with the use of decorators, as well as validation for plain objects. Using class validation involves transforming an object into a class instance using the syntax new Class(). Please refer to the Validating plain objects section for further details.

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