tp5中异常处理 Exception

一、固有思维模式

       目录结构

 

//banner控制器
<?php

namespace app\api\controller\v1;

use app\api\validate\IDMustBePostiveInt;
use app\api\model\Banner as BannerModel;
use think\Exception;

class Banner
{
    public function getBanner($id){

        (new IDMustBePostiveInt()) -> goCheck();

        try{
            $banner = BannerModel::getBannerById($id);
            return $banner;
        }catch (Exception $ex){
            $error = [
                'error_code' => 10001,
                'msg' => $ex -> getMessage()
            ];
            return json($error, 400);
        }

    }
}

//mode  Banner
<?php

namespace app\api\model;

use think\Exception;

class Banner
{
    public static function getBannerById($id)
    {
        try{
            1/0;
        }catch (Exception $ex){
            throw $ex;
        }
        return 'this is banner info';
    }
}

//验证层 基类
<?php

namespace app\api\validate;

use think\Exception;
use think\Request;
use think\Validate;

class BaseValidate extends Validate
{
    public function goCheck(){
        //获取http传入的参数
        //对这些参数做校验
        $request = Request::instance();
        $params = $request -> param();

        $result = $this -> check($params);
        if(!$result){
            $error = $this->getError();
            throw new Exception($error);
        }else{
            return true;
        }
    }
}

//验证层  id必须为正整数
<?php

namespace app\api\validate;

class IDMustBePostiveInt extends BaseValidate
{
    protected $rule = [
      'id' => 'require|isPostiveInteger'
    ];

    //field是字段名
    protected function isPostiveInteger($value, $rule = '', $data = '', $field = ''){
        if(is_numeric($value) && is_int($value + 0) && ($value + 0) > 0){
            return true;
        }else{
            return $field.'必须是正整数';
        }
    }
}

二、总结异常分类

1、由于用户行为导致的异常(没有通过验证器，没有查询到结果)
    通常不需要记录日志      需要向用户返回具体信息

2、服务器自身异常(代码错误、调用外部接口异常)
    通常记录日志     不向用户返回具体信息

三、自定义全局异常处理

       目录结构

//控制器 Banner
<?php

namespace app\api\controller\v1;

use app\api\validate\IDMustBePostiveInt;
use app\api\model\Banner as BannerModel;
use app\lib\exception\BannerMissException;
use think\Exception;

class Banner
{
    public function getBanner($id){

        (new IDMustBePostiveInt()) -> goCheck();
        $banner = BannerModel::getBannerById($id);

        if(!$banner){
            //抛出异常   方式一
            //throw new Exception;

            //抛出异常   方式二   自定义异常
            throw new BannerMissException();
        }
        return $banner;

    }
}

//mode层  getBannerById
<?php

namespace app\api\model;

class Banner
{
    public static function getBannerById($id)
    {
        return null;
    }
}

//轮播图没找到异常  BannerMissException
<?php

namespace app\lib\exception;

class BannerMissException extends BaseException
{
    public $code = 404;
    public $msg = '请求Banner不存在';
    public $errorCode =  40000;
}

//异常基类
<?php

namespace app\lib\exception;

use think\Exception;

class BaseException extends Exception
{
    //HTTP 状态码 404,200
    public $code = 400;

    //错误具体信息
    public $msg =  '参数错误';

    //自定义的错误码
    public $errorCode = 10000;
}

//程序种抛出的异常，会一层层向上抛出。若一直没有处理，会到达最终的异常处理类handle类 \think\exception\Handle
//我们继承 Handle类   并重写了render方法
//修改config.php中  系统Handle的位置  这样异常就会抛到我们自定义的Handle类
'exception_handle'       => 'app\lib\exception\ExceptionHandler',

//自定义的handle类  修改config.php后启用
//render方法  需要传入\Exception  而不是Exception  
//因为有时会出现 Exception外的异常  这样就会报错  \Exception是基类兼容所有异常
<?php

namespace app\lib\exception;

use think\Exception;
use think\exception\Handle;
use think\Request;

class ExceptionHandler extends Handle
{
    private $code;
    private $msg;
    private $errorCode;
    //客户要返回客户端的URL路径

    public function render(\Exception $e)
    {

        if($e instanceof BaseException){
            //如果是自定义的异常
            $this -> code = $e -> code;
            $this -> msg = $e -> msg;
            $this -> errorCode = $e -> errorCode;

        }else{
            //如果不是自定义的异常
            $this -> code = 500;
            $this -> msg = '服务器内部错误，不想告诉你！';
            $this -> errorCode = 999;
        }

        $request = Request::instance();
        $result = [
          'msg' => $this -> msg,
          'error_code' => $this -> errorCode,
          'request_url' => $request -> url()
        ];

        return json($result, $this -> code);
    }
}