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第十四步 用户认证

高级模版装好以后，前端frontend的用户认证就已经完成了

常用代码说明：
//检测当前用户身份
$identity = Yii::$app->user->identity;

//获取用户id，未认证用户为Null
$id = Yii::$app->user->id;

//判断当前用户是否是游客
$isGuest = Yii::$app->user->isGuest;

//将当前用户的身份登记到yii\web\User。根据设置用session或cookie记录用户身份，用户的认证状态将在整个会话中得以维持。
Yii::$app->user->login($identity);

//注销用户
Yii::$app->user->logout();

后端用户认证

前端用户的默认认证类是User，对应前端用户的user表，后端用户表是adminuser，而后端用户的默认模版安装的认证类还是user显然就不对了，所以这儿

1.修改backend/config/main.php:

'identityClass' => 'common\models\Adminuser',

另外，要实现后端用户认证可以参考前端用户认证代码来改。

2.修改common/models/Adminuser.php:

<?php

namespace common\models;

use Yii;
use yii\web\IdentityInterface;
/**
 * This is the model class for table "adminuser".
 *
 * @property int $id
 * @property string $username
 * @property string $nickname
 * @property string $password
 * @property string $email
 * @property string|null $profile
 * @property string $auth_key
 * @property string $password_hash
 * @property string|null $password_reset_token
 *
 * @property Post[] $posts
 */
class Adminuser extends \yii\db\ActiveRecord implements IdentityInterface
{
    /**
     * {@inheritdoc}
     */
    public static function tableName()
    {
        return 'adminuser';
    }

    /**
     * {@inheritdoc}
     */
    public function rules()
    {
        return [
            [['username', 'nickname', 'password', 'email', 'auth_key', 'password_hash'], 'required'],
            [['profile'], 'string'],
            [['username', 'nickname', 'password', 'email'], 'string', 'max' => 128],
            [['auth_key'], 'string', 'max' => 32],
            [['password_hash', 'password_reset_token'], 'string', 'max' => 255],
        ];
    }

    /**
     * {@inheritdoc}
     */
    public function attributeLabels()
    {
        return [
            'id' => 'ID',
            'username' => 'Username',
            'nickname' => 'Nickname',
            'password' => 'Password',
            'email' => 'Email',
            'profile' => 'Profile',
            'auth_key' => 'Auth Key',
            'password_hash' => 'Password Hash',
            'password_reset_token' => 'Password Reset Token',
        ];
    }

    /**
     * @return \yii\db\ActiveQuery
     */
    public function getPosts()
    {
        return $this->hasMany(Post::className(), ['author_id' => 'id']);
    }

    /**
     * {@inheritdoc}
     */
    public static function findIdentity($id)
    {
        return static::findOne(['id' => $id]);
    }

    /**
     * {@inheritdoc}
     */
    public static function findIdentityByAccessToken($token, $type = null)
    {
        throw new NotSupportedException('"findIdentityByAccessToken" is not implemented.');
    }

    /**
     * Finds user by username
     *
     * @param string $username
     * @return static|null
     */
    public static function findByUsername($username)
    {
        return static::findOne(['username' => $username]);
    }

    /**
     * Finds user by password reset token
     *
     * @param string $token password reset token
     * @return static|null
     */
    public static function findByPasswordResetToken($token)
    {
        if (!static::isPasswordResetTokenValid($token)) {
            return null;
        }

        return static::findOne([
            'password_reset_token' => $token,
           // 'status' => self::STATUS_ACTIVE,
        ]);
    }

    /**
     * Finds user by verification email token
     *
     * @param string $token verify email token
     * @return static|null
     */
    public static function findByVerificationToken($token) {
        return static::findOne([
            'verification_token' => $token,
           // 'status' => self::STATUS_INACTIVE
        ]);
    }

    /**
     * Finds out if password reset token is valid
     *
     * @param string $token password reset token
     * @return bool
     */
    public static function isPasswordResetTokenValid($token)
    {
        if (empty($token)) {
            return false;
        }

        $timestamp = (int) substr($token, strrpos($token, '_') + 1);
        $expire = Yii::$app->params['user.passwordResetTokenExpire'];
        return $timestamp + $expire >= time();
    }

    /**
     * {@inheritdoc}
     */
    public function getId()
    {
        return $this->getPrimaryKey();
    }

    /**
     * {@inheritdoc}
     */
    public function getAuthKey()
    {
        return $this->auth_key;
    }

    /**
     * {@inheritdoc}
     */
    public function validateAuthKey($authKey)
    {
        return $this->getAuthKey() === $authKey;
    }

    /**
     * Validates password
     *
     * @param string $password password to validate
     * @return bool if password provided is valid for current user
     */
    public function validatePassword($password)
    {
        return Yii::$app->security->validatePassword($password, $this->password_hash);
    }

    /**
     * Generates password hash from password and sets it to the model
     *
     * @param string $password
     */
    public function setPassword($password)
    {
        $this->password_hash = Yii::$app->security->generatePasswordHash($password);
    }

    /**
     * Generates "remember me" authentication key
     */
    public function generateAuthKey()
    {
        $this->auth_key = Yii::$app->security->generateRandomString();
    }

    /**
     * Generates new password reset token
     */
    public function generatePasswordResetToken()
    {
        $this->password_reset_token = Yii::$app->security->generateRandomString() . '_' . time();
    }

    /**
     * Generates new token for email verification
     */
    public function generateEmailVerificationToken()
    {
        $this->verification_token = Yii::$app->security->generateRandomString() . '_' . time();
    }

    /**
     * Removes password reset token
     */
    public function removePasswordResetToken()
    {
        $this->password_reset_token = null;
    }
}

3.修改backend/controllers/siteController.php:

LoginForm已经被前端用了，所以这儿用一个新的BackLoginForm

use common\models\BackLoginForm;
public function actionLogin()
{...
$model = new BackLoginForm();
...
}

4.把common/models/LoginForm.php拷贝一份，重新命名为BackLoginForm.php并修改对应代码：

class BackLoginForm extends Model
{
 public function attributeLabels()
    {
        return [
            'username' => '用户名',
            'password' => '密码',
            'rememberMe'=>'记住密码',
        ];
    }

 protected function getUser()
    {
        if ($this->_user === null) {
            $this->_user = Adminuser::findByUsername($this->username);
        }

        return $this->_user;
    }
}

5.汉化视图backend/views/site/login.php：