Yii2 中实现单点登录的方法

<?php
// session 跨域
$host = explode('.', $_server["http_host"]);
if (count($host) > 2) {
  define('domain', $host[1] . '.' . $host[2]);
} else {
  define('domain', $host[0] . '.' . $host[1]);
}

<?php
'user' => [
  'identityclass' => 'commonmodelsuser',
  'enableautologin' => true,
  'identitycookie' => ['name' => '_identity', 'httponly' => true, 'domain' => '.'.domain],
],
'session' => [
  'cookieparams' => ['domain' => '.'.domain, 'lifetime' => 0],
  'timeout' => 3600,
],

<?php
//设置
yii::$app->session['var']='value';
//使用
echo yii::$app->session['var'];
//移除
unset(yii::$app->session['var']);