@d3vtool/validator

DevTool Validator

A Schema validation library.

• Validator

Installation

You can install the package using npm or yarn:

npm

npm install @d3vtool/validator

yarn

yarn add @d3vtool/validator

Validator Examples

1. String Validation

import { Validator, ValidationError, type VInfer } from "@d3vtool/validator";

const usernameSchema = Validator.string().minLength(5);

type Username = VInfer<typeof usernameSchema>;

const username: Username = "popHero83";

const errors = usernameSchema.validateSafely(username)

console.log(errors);

// or

try {
  usernameSchema.validate(username);
} catch(err: unknown) {
  if(err instanceof ValidationError) {
    // do something with it
    console.log(err);
  }
}

2. Number Validation

import { Validator, ValidationError, type VInfer } from "@d3vtool/validator";

const phoneSchema = Validator.number().requiredLength(10);

type Phone = VInfer<typeof phoneSchema>;

const phone: Phone = 1234567890;

const errors = phoneSchema.validateSafely(phone)

console.log(errors);

// or

try {
  phoneSchema.validate(phone);
} catch(err: unknown) {
  if(err instanceof ValidationError) {
    // do something with it
    console.log(err);
  }
}

3. Simple Schema Validation

import { Validator, SchemaValidationError, type VInfer } from "@d3vtool/validator";

const schema = Validator.schema({
  name: Validator.string().minLength(5),
  email: Validator.string().email(),
});

type schema = VInfer<typeof schema>;

const schemaObj: schema = {
  name: "Sudhanshu",
  email: "[e-mail]"
}

const errors = schema.validateSafely(schemaObj);
console.log(errors);

// or

try {
  schema.validate(schemaObj);
} catch(err: unknown) {
  if(err instanceof SchemaValidationError) {
    // do something with it
    console.log(err);
  }
}

4. optional() Schema Validation

import { Validator, SchemaValidationError, type VInfer } from "@d3vtool/validator";

const schema = Validator.schema({
  name: Validator.string().minLength(5), // name is required with a minimum length of 5
  email: Validator.string().email().optional(), // email is optional
});

type schema = VInfer<typeof schema>;

const schemaObj: schema = {
  name: "Sudhanshu",
  email: "[e-mail]", // This is valid, but email can also be omitted
};

const errors = schema.validateSafely(schemaObj);
console.log(errors); // Should show no errors

// or
try {
  schema.validate(schemaObj);
} catch(err: unknown) {
  if(err instanceof SchemaValidationError) {
    // do something with it
    console.log(err);
  }
}

// Example with email missing
const schemaObjWithoutEmail: schema = {
  name: "Sudhanshu",
  // email is omitted, which is allowed because it's optional
};

const errorsWithoutEmail = schema.validateSafely(schemaObjWithoutEmail);
console.log(errorsWithoutEmail); // Should show no errors as email is optional

// or 

try {
  schema.validate(schemaObjWithoutEmail);
} catch(err: unknown) {
  if(err instanceof SchemaValidationError) {
    // do something with it
    console.log(err);
  }
}

Explanation:

• name field: This field is required, and it must be a string with a minimum length of 5 characters.
• email field: This field is optional due to .optional(). If it's provided, it must be a valid email address; if not, the validation will still pass without errors.

Example Behavior:

• If both name and email are provided, the validation will pass.
• If only name is provided and email is omitted, the validation will still pass because email is marked as optional.

5. Schema Validation with Optional and Self-Referencing Fields

import { Validator, SchemaValidationError, type VInfer } from "@d3vtool/validator";

const schema = Validator.schema({
  name: Validator.number().minLength(5),
  email: Validator.string().email(),
  password: Validator.string().password().minLength(8),
  confirmPassword: Validator.string().ref("password").optional(),
});

type schema = VInfer<typeof schema>;

const schemaObj: schema = {
  name: 12345,
  email: "[e-mail]",
  password: "securepassword123",
  confirmPassword: "securepassword123", // Optional, but must match password if provided
}

const errors = schema.validateSafely(schemaObj);

// or

try {
  schema.validate(schemaObj);
} catch(err: unknown) {
  if(err instanceof SchemaValidationError) {
    // do something with it
    console.log(err);
  }
}

Explanation:

• name: The name field must be a number and have a minimum value of 5.
• email: The email field must be a valid email address.
• password: The password field must be at least 8 characters long and a valid password format.
• confirmPassword: The confirmPassword field is optional but, if provided, must match the value of the password field (using ref("password")).

In this example, the validateSafely function will check the provided schemaObj and return any validation errors, ensuring that confirmPassword (if present) matches password.