php - json_decode 呈现的响应内容必须是实现 __toString() 的字符串或对象

Question

我使用 Laravel 和函数json_decode。其中，我在一个流行的模块中使用它，它在我自己的非常简单的测试用例中不起作用。它似乎与我的设置/设置有关。（我在 pagodabox 和本地运行它）。我提供的数据来自 Twitter/Instagram，所以内容是 JSON。

这是它不起作用的示例：

<?php

class InstagramController extends BaseController {

    /*
    |--------------------------------------------------------------------------
    | Default Home Controller
    |--------------------------------------------------------------------------
    |
    | You may wish to use controllers instead of, or in addition to, Closure
    | based routes. That's great! Here is an example controller method to
    | get you started. To route to this controller, just add the route:
    |
    |   Route::get('/', 'HomeController@showWelcome');
    |
    */

    public function read($q)
    {
        $client_id = '#############';

        $uri = 'https://api.instagram.com/v1/tags/'.$q.'/media/recent?client_id='.$client_id;
        $response = $this->sendRequest($uri);

        return json_decode($response);
    }

    public function sendRequest($uri){
        $curl = curl_init($uri);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, 0);
        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, 0);
        $response = curl_exec($curl);
        curl_close($curl);
        return $response;
    }

}