Symfony2.3 PDOH处理一个请求创建的会话过多 - Symfony2.3 PDOHandler too many sessions created on a request

我使用Symfony2.3及其内置的PDOSessionHandler工具将会话存储在数据库中。出于某种原因，似乎每个请求都有多个会话被写入数据库，因此，我登录时遇到了问题

parameters:
    pdo.db_options:
        db_table:    Session
        db_id_col:   id
        db_data_col: session_value
        db_time_col: session_time    
services:
    pdo:
        class: PDO
        arguments:
            dsn:      "mysql:host=%database_host%;port=%database_port%;dbname=%database_name%"
            user:     %database_user%
            password: %database_password%
        calls:
            - [ setAttribute, [3, 2] ] # 'PDO::ATTR_ERRMODE, 'PDO::ERRMODE_EXCEPTION
    session.handler.pdo:
        class:    Symfony'Component'HttpFoundation'Session'Storage'Handler'PdoSessionHandler
        arguments:
            - "@pdo"
            - "%pdo.db_options%"

假设我向https://acme.mybundle.com/app_dev.php作为匿名用户。这是我在Session表中看到的输出示例：

+----+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------+
| id | session_value                                                                                                                                                                                                                                                                    | session_time |
+----+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------+
|  1 | X3NmMl9hdHRyaWJ1dGVzfGE6MTp7czozNDoiX3NlY3VyaXR5LnNlY3VyZWRfYXJlYS50YXJnZXRfcGF0aCI7czozODoiaHR0cHM6Ly9hbGxlbmNvLmRldi5hdmF0YXJuZXd5b3JrLmNvbS8iO31fc2YyX2ZsYXNoZXN8YTowOnt9X3NmMl9tZXRhfGE6Mzp7czoxOiJ1IjtpOjE0MTU2MjU4ODQ7czoxOiJjIjtpOjE0MTU2MjU4ODQ7czoxOiJsIjtzOjE6IjAiO30= |   1415625884 |
|  2 | X3NmMl9hdHRyaWJ1dGVzfGE6MDp7fV9zZjJfZmxhc2hlc3xhOjA6e31fc2YyX21ldGF8YTozOntzOjE6InUiO2k6MTQxNTYyNTg4NDtzOjE6ImMiO2k6MTQxNTYyNTg4NDtzOjE6ImwiO3M6MToiMCI7fQ==                                                                                                                     |   1415625884 |
+----+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------+

如果你需要，这里是我的security.yml文件：

security:
    encoders:
        Symfony'Component'Security'Core'User'User: plaintext
        Acme'MyBundle'Entity'User: sha512
    providers:
        main:
            id: acme.user.provider
    firewalls:
        dev:
            pattern: ^/(_(profiler|wdt)|css|images|js)/
            security: false
        login_firewall:
            pattern: ^/login$
            security: false
        secured_area:
            pattern: ^/
            form_login: ~
            logout:
                path:   /logout
                target: /
    access_control:
        - { path: ^/login$, roles: IS_AUTHENTICATED_ANONYMOUSLY, requires_channel: https }
        - { path: ^/, roles: ROLE_USER, requires_channel: https }

在1-5次尝试后，我通常能够登录，并且不会为任何未来的请求创建更多的会话。最后，我们的服务器在一个相关的代理后面。有人知道为什么每个请求都会写多个会话吗？谢谢

原来问题出在我的ORM Session实体上。我有以下$id条目：

<?php
namespace Acme'MyBundle'Entity;
use Doctrine'ORM'Mapping as ORM;
/**
 * Session
 *
 * @ORM'Table()
 * @ORM'Entity
 */
class Session
{
/**
 * @var integer
 *
 * @ORM'Column(name="id", type="integer")
 * @ORM'Id
 * @ORM'GeneratedValue(strategy="AUTO")
 */
private $id;
//...
}

会话的$id不应该是整数——它应该是字符串（显然它也不应该自动递增。在发现这个错误后，我进行了多次derp）。在将我的类的$id条目重写为：之后

/**
 * @var string
 *
 * @ORM'Column(type="string", length=255)
 * @ORM'Id
 */
private $id;

并且运行php app/console doctrine:schema:update --force，一切似乎都正常工作。