关于RBAC的原理讲解在网上可以找到很多，推荐：编程浪子的RBAC讲解，本篇博客就不再累述RBAC的原理到底是什么样的.
传统的权限控制有ACL和RBAC方式，ACL的耦合度很高，扩展性不佳，RBAC很好的解耦合，将权限控制的整个过程涉及的数据表大致分为5张表格：
- user表
- role表
- access表（存储资源数据）
- user_role表
- role_access表
下面是使用原生PHP来实现RBAC权限控制，是一个很简单的例子，因为重在理解这个原理，所以要修改的地方有很多，但是，如果跟着代码一步一步来，那你肯定对RBAC有更深的理解，同时也会发现很多问题，比如多对多的数据表该怎么设计。。。。。
话不多说，先看一下代码吧，代码已经提交到github：https://github.com/searchingbeyond/RBAC-IN-PHP
先看一下目录结构：
然后我会按照便于理解原理的顺序来展示代码：
/RBAC/backend/index.php 后台管理的主页面
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div>
<table>
<tr>
<td><a href="https://my.oschina.net//u/4343669/blog/4230070/UserList.php">用户列表</a></td>
<td><a href="https://my.oschina.net//u/4343669/blog/4230070/RoleList.php">角色管理</a></td>
<td><a href="https://my.oschina.net//u/4343669/blog/4230070/AccessList.php">权限管理</a></td>
</tr>
<tr>
<td><a href="https://my.oschina.net//u/4343669/blog/4230070/AddUser.php">添加用户</a></td>
<td><a href="https://my.oschina.net//u/4343669/blog/4230070/AddRole.php">添加角色</a></td>
<td><a href="https://my.oschina.net//u/4343669/blog/4230070/AddAccess.php">增加资源</a></td>
</tr>
</table>
</div>
</body>
</html>
/RBAC/backend/AddUser.php 添加用户
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>创建用户</title>
</head>
<body>
<div>
<table>
<form action="" method="post">
<caption>用户信息</caption>
<tr>
<td>用户ID:</td>
<td><input type="text" name="user_id" style="width:400px"></td>
</tr>
<tr>
<td>用户名:</td>
<td><input type="text" name="user_name" style="width:400px"></td>
</tr>
<tr>
<td colspan="2">
<input type="submit" name="adduser" value="添加">
<input type="button" value="返回首页" onclick="location.href='./index.php'">
</td>
</tr>
</form>
</table>
</div>
</body>
</html>
<?php
if( isset($_POST['adduser']) ){
$user_id = $_POST['user_id'];
$user_name = $_POST['user_name'];
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("insert into user (user_id,user_name) values ( :user_id, :user_name )");
$stmt->execute(array(":user_id"=>$user_id,":user_name"=>$user_name));
}
?>
/RBAC/backend/UserList.php 显示用户列表
<?php
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("select * from user");
$stmt->execute();
$user_arr = $stmt->fetchAll(PDO::FETCH_ASSOC);
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>用户管理</title>
</head>
<body>
<div>
<table>
<caption>用户列表</caption>
<tr>
<td>用户名</td>
<td>状态</td>
<td>操作</td>
</tr>
<?php if( count($user_arr) ): ?>
<?php foreach($user_arr as $user): ?>
<tr>
<td><?php echo $user['user_name']; ?></td>
<td><?php echo $user['user_status']?"正常":"禁用"; ?></td>
<td>
<a href="EditUser.php?user_id=<?php echo $user['user_id']?>">角色设置</a>
</td>
</tr>
<?php endforeach; ?>
<?php endif; ?>
</table>
</div>
</body>
</html>
/RBAC/backend/EditUser.php 用于设置用户的角色
<?php
if( isset($_GET['user_id']) ){
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
//查询用户信息
$stmt = $pdo->prepare("select * from user where user_id = :user_id");
$stmt->execute(array("user_id" => $_GET['user_id']));
$user_info = $stmt->fetch(PDO::FETCH_ASSOC);
//print_r($user_info);
//查询用户的角色
$stmt = $pdo->prepare("select * from user_role where user_id = :user_id");
$stmt->execute(array(":user_id" => $_GET['user_id']));
//这里只留下role_id
$user_role_info = array_column( $stmt->fetchAll(PDO::FETCH_ASSOC),"role_id" );
//print_r($user_role_info);
//查询所有角色
$stmt = $pdo->prepare("select * from role");
$stmt->execute();
$role_arr = $stmt->fetchAll(PDO::FETCH_ASSOC);
//print_r($role_arr);
}
//用来判断复选框已选中
function checked($i,$arr){
if( in_array($i,$arr) ){
echo "checked";
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div>
<form action="" method='post'>
<table>
<caption>用户信息</caption>
<tr>
<td>用户名:</td>
<td>
<input type="hidden" name="user_id" value="<?php echo $user_info['user_id'] ?>">
<?php echo $user_info['user_name']; ?>
</td>
</tr>
<tr>
<td>角色:</td>
<?php if( count($role_arr) ):?>
<?php foreach($role_arr as $role): ?>
<td>
<div>
<input type="checkbox" <?php checked($role['role_id'],$user_role_info);?> name="role[]" value="<?php echo $role['role_id'];?>"><?php echo $role['role_name'] ?>
</div>
</td>
<?php endforeach; ?>
<?php endif; ?>
</tr>
<tr>
<td colspan="5">
<input type="submit" name="editUser">
<input type="button" value="返回主页" onclick="location.href='./index.php'">
<input type="button" value="返回用户列表" onclick="location.href='./UserList.php'">
</td>
</tr>
</table>
</form>
</div>
</body>
</html>
<?php
if( isset($_POST['editUser'])){
//获取传递的role复选框数组，当将全部角色都撤销时，传递的post数据中将不再有role，所以将其设为空数组。
$edit_role = isset($_POST['role'])?$_POST['role']:array();
$user_id = $_POST['user_id'];
//增加的角色：
$add_role = array_diff($edit_role,$user_role_info);
//删除的角色
$sub_role = array_diff($user_role_info,$edit_role);
//执行删除角色
$stmt = $pdo->prepare("delete from user_role where user_id = :user_id and role_id = :role_id");
foreach($sub_role as $role_id){
$stmt->execute(array(":user_id"=>$user_id,":role_id"=>$role_id));
}
//执行增加角色
$stmt = $pdo->prepare("insert into user_role (user_id,role_id) values(:user_id,:role_id)");
foreach($add_role as $role_id){
$stmt->execute(array(":user_id"=>$user_id,":role_id"=>$role_id));
}
// echo "<script>location.href='editUser.php?user_id=$user_id</script>";
echo "<script>location.replace(location.href);</script>";
}
?>
其实看到这里，大概就知道RBAC是怎么简单实现的了，下面几个文件和上面的文件很相似；
/RBAC/backend/AddRole.php 添加一个角色
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>创建角色</title>
</head>
<body>
<div id="container">
<table>
<form action="" method="post">
<caption>角色信息</caption>
<tr>
<td>角色名:</td>
<td><input type="text" name="role_name" style="width:300px"></td>
</tr>
<tr>
<td colspan="2">
<input type="submit" name="addrole" value="添加">
<input type="button" value="返回首页" onclick="location.href='./index.php'">
</td>
</tr>
</form>
</table>
</div>
</body>
</html>
<?php
if( isset($_POST['addrole']) ){
$role_name = $_POST['role_name'];
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("insert into role (role_name) values ( :role_name )");
$stmt->execute(array(":role_name"=>$role_name));
}
?>
/RBAC/backend/RoleList.php 显示角色的列表
<?php
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("select * from role");
$stmt->execute();
$role_arr = $stmt->fetchAll(PDO::FETCH_ASSOC);
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>角色管理</title>
</head>
<body>
<div>
<table>
<caption>角色列表</caption>
<tr>
<td>角色名</td>
<td>操作</td>
</tr>
<?php if( count($role_arr) ): ?>
<?php foreach($role_arr as $role): ?>
<tr>
<td><?php echo $role['role_name']; ?></td>
<td>
<a href="EditRole.php?role_id=<?php echo $role['role_id']?>">权限设置</a>
</td>
</tr>
<?php endforeach; ?>
<?php endif; ?>
</table>
</div>
</body>
</html>
/RBAC/backend/EditRole.php 编辑角色可以获得哪些资源（权限access)
<?php
if( isset($_GET['role_id']) ){
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
//查询角色信息
$stmt = $pdo->prepare("select * from role where role_id = :role_id");
$stmt->execute(array("role_id" => $_GET['role_id']));
$role_info = $stmt->fetch(PDO::FETCH_ASSOC);
//print_r($user_info);
//查询当前角色拥有的权限
$stmt = $pdo->prepare("select * from role_access where role_id = :role_id");
$stmt->execute(array(":role_id" => $_GET['role_id']));
//这里只留下access_id
$role_access_info = array_column( $stmt->fetchAll(PDO::FETCH_ASSOC),"access_id" );
//print_r($user_role_info);
//查询所有的资源信息
$stmt = $pdo->prepare("select * from access");
$stmt->execute();
$access_arr = $stmt->fetchAll(PDO::FETCH_ASSOC);
//print_r($role_arr);
}
//用来判断复选框已选中
function checked($i,$arr){
if( in_array($i,$arr) ){
echo "checked";
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>编辑角色</title>
</head>
<body>
<div style="width:400px;margin:0 auto">
<form action="" method='post'>
<table>
<caption>角色信息</caption>
<tr>
<td>角色名:</td>
<td>
<input type="hidden" name="role_id" value="<?php echo $role_info['role_id'] ?>">
<?php echo $role_info['role_name']; ?>
</td>
</tr>
<tr>
<td>权限:</td>
<?php if( count($access_arr) ):?>
<td>
<?php foreach($access_arr as $access): ?>
<div>
<input type="checkbox" <?php checked($access['access_id'],$role_access_info);?> name="access[]" value="<?php echo $access['access_id']?>"><?php echo $access['title'] ?>
</div>
<?php endforeach; ?>
</td>
<?php endif; ?>
</tr>
<tr>
<td colspan="5">
<input type="submit" name="editRole">
<input type="button" value="返回主页" onclick="location.href='./index.php'">
<input type="button" value="返回角色列表" onclick="location.href='./RoleList.php'">
</td>
</tr>
</table>
</form>
</div>
</body>
</html>
<?php
if( isset($_POST['editRole'])){
//获取传递的role复选框数组，当将全部角色都撤销时，传递的post数据中将不再有role，所以将其设为空数组。
$access = isset($_POST['access'])?$_POST['access']:array();
$role_id = $_POST['role_id'];
//增加的角色：
$add_access = array_diff($access,$role_access_info);
//删除的角色
$sub_access = array_diff($role_access_info,$access);
//执行删除角色
$stmt = $pdo->prepare("delete from role_access where role_id = :role_id and access_id = :access_id");
foreach($sub_access as $access_id){
$stmt->execute(array(":role_id"=>$role_id,":access_id"=>$access_id ));
}
//执行增加角色
$stmt = $pdo->prepare("insert into role_access (role_id,access_id) values(:role_id,:access_id)");
foreach($add_access as $access_id){
$stmt->execute(array(":role_id"=>$role_id,":access_id"=>$access_id ));
}
echo "<script>location.replace(location.href);</script>";
}
?>
/RBAC/backend/AddAccess.php 添加一个权限（资源）
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>创建访问资源</title>
</head>
<body>
<div>
<table>
<form action="" method="post">
<caption>资源信息</caption>
<tr>
<td>资源名:</td>
<td><input type="text" name="title" style="width:400px"></td>
</tr>
<tr>
<td>URLs:</td>
<td>
<textarea style="margin-top:20px;width:400px;height:200px" name="urls"></textarea>
</td>
</tr>
<tr>
<td colspan="2">
<input type="submit" name="addaccess" value="添加">
<input type="button" value="返回首页" onclick="location.href='./index.php'">
</td>
</tr>
</form>
</table>
</div>
</body>
</html>
<?php
if( isset($_POST['addaccess']) ){
$title = $_POST['title'];
$urls = json_encode( explode(",",$_POST['urls']) );
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("insert into access (title,urls) values ( :title, :urls )");
$stmt->execute(array(":title"=>$title,":urls"=>$urls));
}
?>
/RBAC/backend/AccessList.php 资源（权限）列表
<?php
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("select * from access");
$stmt->execute();
$access_arr = $stmt->fetchAll(PDO::FETCH_ASSOC);
function print_json($data){
$arr = json_decode($data,true);
foreach($arr as $v ){
echo $v."<br>";
}
}
?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>资源管理</title>
</head>
<body>
<div id="container">
<table>
<caption>资源列表</caption>
<tr>
<td>资源ID</td>
<td>名称</td>
<td>urls</td>
<td>操作</td>
</tr>
<?php if( count($access_arr) ): ?>
<?php foreach($access_arr as $access): ?>
<tr>
<td><?php echo $access['access_id']; ?></td>
<td><?php echo $access['title']; ?></td>
<td><?php print_json($access['urls']); ?></td>
<td>
<a href="EditAccess.php?access_id=<?php echo $access['access_id']?>">资源设置</a>
</td>
</tr>
<?php endforeach; ?>
<?php endif; ?>
</table>
</div>
</body>
</html>
到这里，基本的权限系统就已经建立好了，但是缺少实例，而且还有检测权限的操作。
/RBAC/frontend/index.php 前台首页
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>首页</title>
</head>
<body>
<h2><a href="https://my.oschina.net//u/4343669/blog/4230070/pageone.php">pageone.php</a></h2>
<h2><a href="https://my.oschina.net//u/4343669/blog/4230070/pagetwo.php">pagetwo.php</a></h2>
<h2><a href="https://my.oschina.net//u/4343669/blog/4230070/pagethree.php">pagethree.php</a></h2>
</body>
</html>
/RBAC/frontend/pageone.php 测试页面1
<?php include "checkPermission.php" ?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>pageOne</title>
</head>
<body>
<h1>pageOne</h1>
<input type="button" onclick="history.back()" value="返回">
</body>
</html>
/RBAC/frontend/pagetwo.php 测试页面2
<?php include "checkPermission.php" ?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>pageTwo</title>
</head>
<body>
<h1>pageTwo</h1>
<input type="button" onclick="history.back()" value="返回">
</body>
</html>
/RBAC/frontend/pagethree.php 测试页面3
<?php include "checkPermission.php" ?>
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>pageThree</title>
</head>
<body>
<h1>pageThree</h1>
<input type="button" onclick="history.back()" value="返回">
</body>
</html>
/RBAC/frontend/checkPermission.php 检测权限
<?php
//此处为了测试，不进行检查
// 真正使用的时候，应该使用下面一个php代码
$user_id="666";
$user_name="beyond";
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("select count(*) from user where user_id=:user_id and user_name=:user_name;");
$stmt->execute(array(":user_id"=>$user_id,":user_name"=>$user_name));
$flag = $stmt->fetch(PDO::FETCH_ASSOC);
!$flag && die("无此用户");
$stmt = $pdo->prepare("select * from user
left join user_role on user.user_id = user_role.user_id
right join role_access on user_role.role_id = role_access.role_id
left join access on access.access_id = role_access.access_id
where user.user_id = :user_id
");
$stmt->execute(array(":user_id"=>$user_id));
$data = $stmt->fetchAll(PDO::FETCH_ASSOC);
//urls用来保存当前用户所拥有的权限url
//可以保存在缓存中，提高效率
$urls = array();
foreach( $data as $v ){
$urls[] = json_decode($v['urls'],true)[0];
}
//判断对当前url是否有权限
if ( ! in_array( $_SERVER['SCRIPT_NAME'], $urls ) ){
include "error.html";
exit;
}
?>
<?php
/*
真正使用的时候，应该使用这个
//因为重点不是验证登录，所以这里简单的验证登录
if( $_SESSION['user_id'] && $_SESSION['user_name'] ){
$pdo = new PDO("mysql:host=127.0.0.1;dbname=rbac","root","123456");
$stmt = $pdo->prepare("select count(*) from user where user_id=:user_id and user_name=:user_name;");
$stmt->execute(array(":user_id"=>$_SESSION['user_id'],":user_name"=>$_SESSION['user_name']));
$flag = $stmt->fetch(PDO::FETCH_ASSOC);
!$flag && die("无此用户");
$stmt = $pdo->prepare("select * from user
left join user_role on user.user_id = user_role.user_id
right join role_access on user_role.role_id = role_access.role_id
left join access on access.access_id = role_access.access_id
where user.user_id = :user_id
");
$stmt->execute(array("user_id"=>$_SESSION['user_id']));
$data = $stmt->fetchAll(PDO::FETCH_ASSOC);
$urls = array();
foreach( $data as $v ){
$urls[] = json_decode($v['urls'],true)[0];
}
if ( ! in_array( $_SERVER['SCRIPT_NAME'], $urls ) ){
include "error.html";
exit;
}
}
*/
?>
/RBAC/frontend/error.html 没有权限时显示
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>无权限</title>
</head>
<body>
<h2>你没有权限查看该页面，请联系管理员开通</h2>
</body>
</html>
