Walle/models/forms/PasswordResetRequestForm.php

<?php
namespace app\models\forms;

use Yii;
use yii\base\Model;
use app\models\User;

/**
 * Password reset request form
 */
class PasswordResetRequestForm extends Model
{
    public $email;

    /**
     * @inheritdoc
     */
    public function rules()
    {
        return [
            ['email', 'filter', 'filter' => 'trim'],
            ['email', 'required'],
            ['email', 'email'],
            ['email', 'exist',
                'targetClass' => '\app\models\User',
                'filter' => ['status' => User::STATUS_ACTIVE],
                'message' => 'There is no user with such email.'
            ],
        ];
    }

    /**
     * Sends an email with a link, for resetting the password.
     *
     * @return boolean whether the email was send
     */
    public function sendEmail()
    {
        /** @var User $user */
        $user = User::find()->canLogin()->email($this->email)->one();

        if ($user) {
            $user->generatePasswordResetToken();
            if ($user->save()) {
                $params = Yii::$app->params;
                return Yii::$app->mail->compose('passwordResetToken', ['user' => $user])
                    ->setFrom([$params['support.email'] => $params['support.name']])
                    ->setTo($this->email)
                    ->setSubject('Password reset for ' . Yii::$app->name)
                    ->send();
            }
        }

        return false;
    }
}