Validation

Every create and update already runs through validation, whether you've added any or not: @Column fields are required by default, an empty, null, or missing value is rejected before anything reaches the database. Nothing enforces this outside RepoUtils, no @Validate decorator to remember on every route, the check runs the same way no matter which route, service, or job ends up calling into the datastore.

Making a field optional

Mark a field @Nullable to allow it to be absent:

import { ObjectDecorators } from '@rapidrest/core';
const { Nullable } = ObjectDecorators;

@Column()
@Nullable
avatar?: string;

Without it, saving a Pet with no avatar throws before the write ever happens. 0 and false are real values, not treated as absent, only null, undefined, and "" are.

Validating the value itself

@Validator(func) runs a function against a field's value on every create and update, and can transform it too, whatever it returns is what actually gets stored:

import { ObjectDecorators, ValidationUtils } from '@rapidrest/core';
const { Nullable, Validator } = ObjectDecorators;

@Column()
@Validator(ValidationUtils.checkDate)
@Nullable
birthdate?: Date;

Combining @Validator with @Nullable reads naturally: valid if present, not required. Throw from the function to reject the value, the same way @Validate does at the route level, just scoped to one field instead of a whole request body.

Built-in checks

ValidationUtils (from @rapidrest/core) ships the common ones, so you're not hand-writing a regex for an email address:

Function	Validates
checkEmail	A valid email address
checkURL	A valid URL
checkPhone	A valid phone number
checkUUID	A valid UUID
checkSemVer	A valid semantic version string
checkIP	A valid IP address
checkDate	A valid ISO/RFC/UTC date or timestamp
checkJSON	A valid JSON string
checkName	Matches /^[a-zA-Z0-9_\-.@:+]+$/

None of these fit? ValidationUtils.check(val, func) wraps any boolean predicate of your own into the same throw-on-failure shape, so a custom rule still composes with @Validator the same way:

@Column()
@Validator((val: number) => ValidationUtils.check(val, (v) => v >= 0 && v <= 100))
percentage: number = 0;

Where this runs

@Nullable and @Validator are read by RepoUtils.create()/update() before anything is written, and by extension by Auto CRUD Routes and any of your own code that goes through RepoUtils, or @Transactional methods that call it. This is the same validation mechanism whether the write came from a REST request, a background job, or a script, one set of rules, defined once on the model, rather than re-checked in every place that happens to write to it.