Adonis Class Validator

Adonis Class Validator provides a means to validate a request data using a class schema.

On successful validation, the data returned from validation is an instance of the class schema used to validate the request.

🎁 Features

• Convenient nesting of class rules.
• Easy declaration of custom messages.
• In-built caching of class schema.
• Validate with existing V5 validator.
• Support for all V5 validator features (custom messages, creating custom rules, profiling, reporting etc).

📦 Installing

Simply run the following commands on your shell

npm install adonis-class-validator
node ace invoke adonis-class-validator

📌 Example

We're making use of all the schemas and rules baked into Adonis. 😃

// SignupPayload.ts
import { validate, schema, rules } from "@ioc:Adonis/ClassValidator";

class SignupPayload {
  @validate(schema.string({}, [rules.required(), rules.email()]), {
    required: "Field {{name}} is required.",
    email: "Invalid email address",
  })
  public email!: string;
}

// SignupController.ts
import { SignupPayload } from "App/Validators";
import { HttpContextContract } from "@ioc:Adonis/Core/HttpContext";

class SignupController {
  public async index({ request }: HttpContextContract) {
    const payload = await request.classValidate(SignupPayload);
    console.log(payload instanceof SignupPayload); // true
  }
}

For more examples, check here

Standalone Validator

If you want to make use of the validator class schema to validate any form of data (outside the controller), you can easily rely on the standalone ClassValidator.validate(...) helper function.

NOTE: If the validation fails, an instance of ValidationException is thrown.

import {
  ClassValidator,
  ValidationException,
} from "@ioc:Adonis/ClassValidator";

async function sendEmail() {
  try {
    const payload = await ClassValidator.validate(SignupPayload, {
      email: "hello@stallsone.com",
    });
  } catch (err) {
    // if validation error occurs, `err` is an instance of `ValidationException`
  }
}

⚓️ Going Deeper

There are currently 2 decorators supported for validation. They include:

• @validate() : To validate primitive schemas such as string, boolean, number, date, enum/enumSet, file, array([string|boolean|number|date|enum|file]).
• @validate.nested(): To nest class validator schemas through array and object.

Nested Validation

To nest a class validator schema, simply rely on the @validate.nested() decorator. It requires:

• The class validator schema of the nested field.
• A callback that whose:
  • parameter: is a adonis member equivalent of the validator schema.
  • return type: is the adonis schema to use to validate the nested field (which is either an array or object).
• An optional custom message object.

Custom messages also support interpolation e.g. Field {{name}} is required.

import { validate } from "@ioc:Adonis/ClassValidator";

class Address {
  @validate(schema.number([
    rules.unique({ table: "users", column: "email" })
  ]),
  { unique: 'Field must be unique.' })
  public id!: number;
}

class User {
  @validate.nested(
    Address,
    (address) => schema
      .array([rules.minLength(2)])
      .members(schema.object().members(address)),
    { minLength: "Field {{name}} must contain at least 2 addresses." }
  )
  public addresses!: Address[];

Custom Messages

When request.classValidate(...) is called against the User schema above, the custom message generated and used for the failed validation will be:

{
  "addresses.minLength": "Field addresses must contain at least 2 addresses.",
  "addresses.*.unique": "Field must be unique."
}

As far as the decorated field schema is a schema.array() with a .members(...) of nested validation class, it infers that it as the deep matching (.*.) patter matcher.

Empty Classes

If no property in a class was decorated with validate(), an empty data will be returned (where each field will be undefined).

// Notice there's no schema rule.
class UserPayload {
  public firstname!: string;
}

// UserController.ts
export default class UsersController {
  public async index({ request }: HttpContextContract) {
    const data = await request.classValidate(UserPayload);

    /**
     * Payload wasn't validated because the class doesn't
     * have a property decorated with a schema.
     */
    console.log(data instanceof SignupPayload); // true

    /**
     * Data is empty because no property has a validator schema decorator.
     */
    console.log(payload); // {}
  }
}

📝 Contributing

If you find any issue, bug or missing feature, please kindly create an issue or submit a pull request.

🔖 License

Adonis Class Validator is open-sourced software under MIT license.