accounts/api/models/RegistrationForm.php

<?php
namespace api\models;

use api\components\ReCaptcha\Validator as ReCaptchaValidator;
use common\components\UserFriendlyRandomKey;
use common\models\Account;
use common\models\EmailActivation;
use Ramsey\Uuid\Uuid;
use Yii;
use yii\base\ErrorException;

class RegistrationForm extends BaseApiForm {

    public $username;
    public $email;
    public $password;
    public $rePassword;
    public $rulesAgreement;

    public function rules() {
        return [
            ['rulesAgreement', 'required', 'message' => 'error.you_must_accept_rules'],
            [[], ReCaptchaValidator::class, 'message' => 'error.captcha_invalid', 'when' => !YII_ENV_TEST],

            ['username', 'filter', 'filter' => 'trim'],
            ['username', 'required', 'message' => 'error.username_required'],
            ['username', 'string', 'min' => 3, 'max' => 21,
                'tooShort' => 'error.username_too_short',
                'tooLong' => 'error.username_too_long',
            ],
            ['username', 'match', 'pattern' => '/^[\p{L}\d-_\.!?#$%^&*()\[\]:;]+$/u'],
            ['username', 'unique', 'targetClass' => Account::class, 'message' => 'error.username_not_available'],

            ['email', 'filter', 'filter' => 'trim'],
            ['email', 'required', 'message' => 'error.email_required'],
            ['email', 'string', 'max' => 255, 'tooLong' => 'error.email_too_long'],
            ['email', 'email', 'checkDNS' => true, 'enableIDN' => true, 'message' => 'error.email_invalid'],
            ['email', 'unique', 'targetClass' => Account::class, 'message' => 'error.email_not_available'],

            ['password', 'required', 'message' => 'error.password_required'],
            ['rePassword', 'required', 'message' => 'error.rePassword_required'],
            ['password', 'string', 'min' => 8, 'tooShort' => 'error.password_too_short'],
            ['rePassword', 'validatePasswordAndRePasswordMatch'],
        ];
    }

    public function validatePasswordAndRePasswordMatch($attribute) {
        if (!$this->hasErrors()) {
            if ($this->password !== $this->rePassword) {
                $this->addError($attribute, "error.rePassword_does_not_match");
            }
        }
    }

    /**
     * @return Account|null the saved model or null if saving fails
     */
    public function signup() {
        if (!$this->validate()) {
            return null;
        }

        $transaction = Yii::$app->db->beginTransaction();
        try {
            $account = new Account();
            $account->uuid = Uuid::uuid4();
            $account->email = $this->email;
            $account->username = $this->username;
            $account->password = $this->password;
            $account->status = Account::STATUS_REGISTERED;
            $account->generateAuthKey();
            if (!$account->save()) {
                throw new ErrorException('Account not created.');
            }

            $emailActivation = new EmailActivation();
            $emailActivation->account_id = $account->id;
            $emailActivation->type = EmailActivation::TYPE_REGISTRATION_EMAIL_CONFIRMATION;
            $emailActivation->key = UserFriendlyRandomKey::make();

            if (!$emailActivation->save()) {
                throw new ErrorException('Unable save email-activation model.');
            }

            /** @var \yii\swiftmailer\Mailer $mailer */
            $mailer = Yii::$app->mailer;
            /** @var \yii\swiftmailer\Message $message */
            $message = $mailer->compose([
                'html' => '@app/mails/registration-confirmation-html',
                'text' => '@app/mails/registration-confirmation-text',
            ], [
                'key' => $emailActivation->key,
            ])->setFrom(['account@ely.by' => 'Ely.by']);

            if (!$message->send()) {
                throw new ErrorException('Unable send email with activation code.');
            }

            $transaction->commit();
        } catch (ErrorException $e) {
            $transaction->rollBack();
            throw $e;
        }

        return $account;
    }

}