处理另一个错误时发生错误：yii\web\HeadersAlreadySentException: Headers already sent

Posted 2023-02-23

【中文标题】处理另一个错误时发生错误：yii\\web\\HeadersAlreadySentException: Headers already sent

【英文标题】：An Error occurred while handling another error: yii\web\HeadersAlreadySentException: Headers already sent处理另一个错误时发生错误：yii\web\HeadersAlreadySentException: Headers already sent

【发布时间】：2020-10-15 08:06:44

【问题描述】：

我正在用 yii2 开发一个 rest api web 服务。 作为 localhost 上的 json 响应，json 响应我的 null 对象结束。 并在主机上出现 json 错误结束。

在 localhost 中，我收到的响应如下： 本地主机上的响应：

    "status": 1,
    "data": 
        "data": "Factor Api"
    
null

但在服务器上，我收到的响应如下： 服务器上的响应：

    "status": 1,
    "data": 
        "data": "Factor Api"
    
<pre>An Error occurred while handling another error:
yii\web\HeadersAlreadySentException: Headers already sent in /home/factorap/public_html/common/components/Api.php on line 53. in /home/factorap/public_html/vendor/yiisoft/yii2/web/Response.php:366
Stack trace:
#0 /home/factorap/public_html/vendor/yiisoft/yii2/web/Response.php(339): yii\web\Response-&gt;sendHeaders()
#1 /home/factorap/public_html/vendor/yiisoft/yii2/web/ErrorHandler.php(136): yii\web\Response-&gt;send()
#2 /home/factorap/public_html/vendor/yiisoft/yii2/base/ErrorHandler.php(135): yii\web\ErrorHandler-&gt;renderException(Object(yii\web\HeadersAlreadySentException))
#3 [internal function]: yii\base\ErrorHandler-&gt;handleException(Object(yii\web\HeadersAlreadySentException))
#4 main
Previous exception:
yii\web\HeadersAlreadySentException: Headers already sent in /home/factorap/public_html/common/components/Api.php on line 53. in /home/factorap/public_html/vendor/yiisoft/yii2/web/Response.php:366
Stack trace:
#0 /home/factorap/public_html/vendor/yiisoft/yii2/web/Response.php(339): yii\web\Response-&gt;sendHeaders()
#1 /home/factorap/public_html/vendor/yiisoft/yii2/base/Application.php(656): yii\web\Response-&gt;send()
#2 /home/factorap/public_html/common/components/Api.php(56): yii\base\Application-&gt;end()
#3 /home/factorap/public_html/api/controllers/SiteController.php(92): common\components\Api-&gt;sendSuccessResponse(Array)
#4 [internal function]: api\controllers\SiteController-&gt;actionIndex()
#5 /home/factorap/public_html/vendor/yiisoft/yii2/base/InlineAction.php(57): call_user_func_array(Array, Array)
#6 /home/factorap/public_html/vendor/yiisoft/yii2/base/Controller.php(180): yii\base\InlineAction-&gt;runWithParams(Array)
#7 /home/factorap/public_html/vendor/yiisoft/yii2/base/Module.php(528): yii\base\Controller-&gt;runAction(&#039;&#039;, Array)
#8 /home/factorap/public_html/vendor/yiisoft/yii2/web/Application.php(103): yii\base\Module-&gt;runAction(&#039;&#039;, Array)
#9 /home/factorap/public_html/vendor/yiisoft/yii2/base/Application.php(386): yii\web\Application-&gt;handleRequest(Object(yii\web\Request))
#10 /home/factorap/public_html/api/v2/index.php(17): yii\base\Application-&gt;run()
#11 main</pre>

common/components/Api.php 第 53 行 = $this->setHeader(200);

我发送响应的功能： api函数：

    public function sendSuccessResponse($data = false,$additional_info = false)
    

        $this->setHeader(200);

        $response = [];
        $response['status'] = 1;

        if (is_array($data))
            $response['data'] = $data;

        if ($additional_info) 
            $response = array_merge($response, $additional_info);
        

        $response = Json::encode($response, JSON_PRETTY_PRINT);
        //$strpos = strpos($response,'null');


        if (isset($_GET['callback'])) 
            /* this is required for angularjs1.0 client factory API calls to work */
            $response = $_GET['callback'] . "(" . $response . ")";

            echo $response;
         else 
            echo $response;
        

        Yii::$app->end();

    

和要运行的控制器动作。 控制器动作：

    public function actionIndex()
    
        Yii::$app->api->sendSuccessResponse(['data' => 'Factor Api']);
    

请帮我修复它们。

【问题讨论】：

不要回显输出，返回它。

【参考方案1】：

还有另一种方法可以做到这一点。像这样：frontend/controllers/ApiController.php

class ApiController extends \yii\rest\Controller

    public function behaviors()
    
        return [
            'contentNegotiator' => [
                'class'   => \yii\filters\ContentNegotiator::className(),
                'formats' => [
                    'application/json' => yii\web\Response::FORMAT_JSON,
                ],
            ],
        ];
    

    public function actionApi()
    
        $model = \common\models\User::find()->one();

        return $model->getAttributes();
    

frontend/config/main.php:

return [
    // other code
    'components'          => [
        // other code
        'request'      => [
            'enableCookieValidation' => true,
            'cookieValidationKey'    => 'Ci@1ouPTLKXn9s6myzsfsef2UtTfKwjpnWO',
            'parsers'                => [
                'application/json' => 'yii\web\JsonParser',
            ],
        ],
        'urlManager'   => [
            'enablePrettyUrl'     => true,
            'enableStrictParsing' => true,
            'showScriptName'      => false,
            'rules'               => [
                '<controller:\w+>/<action:\w+>' => '<controller>/<action>',
                ['class' => 'yii\rest\UrlRule', 'controller' => 'api'],
            ],
        ],
        // other code
    ],
];

打开http://yoursite.com/api/users

    id: 1,
    username: "admin",
    auth_key: "IVi31eKxa-EE3ki7X7ToKb6uO8dknNrV",
    password_hash: "$2y$13$oMiNRYUYb0gPcWpheiYdb.0Xs/lWk7Ixcb.F5ch38ExbiSok1TfRi",
    password_reset_token: null,
    email: "[e-mail]",
    status: 10,
    created_at: 1603274263,
    updated_at: 1603274263,
    verification_token: "cTnvRiub3BpoCEwx-yFUb10zCtu0TpxK_1603274263",