Comparing password fields

[ChrLipp]

I am using class-validator to validate my incoming requests in an express application and I am very happy with it.

Currently I am implementing a registration service, my request has two password fields, password and password2. I would like to compare them to each other but it seems that this functionality is lacking in class-validator.

Is class-validator able to handle this scenario already or is this a feature request?

[pleerock]

Using Custom validation classes and Custom validation decorators you can create a complex validations like in your case

[ChrLipp]

I had the opinion that this solutions are only suited for validating single fields, not for comparing two fields.

E.g. validation classes:

// one field value called text in your doc
 validate(text: string, ...

validation decorator:

// one field with value
validate(value: any, ...

I had the hope that

@Equals(this.password2)
public password: string;

would solve this, but this is not bound for the validating annotations.

[pleerock]

no its totally possible to implement. Take a look on this example it does exactly what you want - make comparasion on a different property of the same object.

[ChrLipp]

IsLongerThan looks promising, I will try that.
Thanks for your work!

Regards, Christian

[ChrLipp]

Unfortunately this code doesn't compile.

error TS2345: Argument of type '{ constraints: string[]; options: ValidationOptions | undefined; propertyName: string; target: Fu...' is not assignable to parameter of type 'ValidationDecoratorOptions'.
  Types of property 'options' are incompatible.
    Type 'ValidationOptions | undefined' is not assignable to type 'ValidatorOptions'.
      Type 'undefined' is not assignable to type 'ValidatorOptions'.

The version of typescript is

"typescript": "2.1.4",

It works when the second param is not optional.

export function IsEqualTo(property: string, validationOptions: ValidationOptions) {