先貼上圖片上傳文件地址
https://pay.weixin.qq.com/wiki/doc/api/download/img_upload.pdf

圖片上傳介面返回的media_id在申請入駐介面時有用，所以一開始就得把這個調通，才能繼續往下走申請入駐介面。
下面直接上程式碼看著清楚點

<?php
    /**
     * uploadMedia.php
     *
     * Created by PhpStorm.
     * author: liuml  
     * DateTime: 2018/8/24  13:59
     */

    namespace
 
 App\Wechat\V1\Services\wechat\traits;

    use App\Wechat\V1\exception\WxException;
    use Illuminate\Support\Facades\Config;
    use Illuminate\Support\Facades\Request;

    trait UploadMedia
    {
        protected $media_addr;

        public function uploadImg()
        {
            $url = self
 
::WXAPIHOST . 'secapi/mch/uploadmedia';
            // 判斷圖片地址是否為空，空的話就呼叫圖片上傳方法，把圖片上傳到伺服器
            empty($this->media_addr) && $this->saveImg();
            // 判斷圖片是否存在
            if (!file_exists($this->media_addr))
                throw new WxException(10001);
            $data              = [
                'mch_id'
 
     => $this->mch_id,
                'media_hash' => md5_file($this->media_addr),
            ];
            $data['sign_type'] = 'HMAC-SHA256';
            // 生成簽名
            $data['sign']      = $this->makeSign($data, $data['sign_type']);
            // CURLFile 類的解釋 http://php.net/manual/zh/class.curlfile.php
            $data['media']     = new \CURLFile($this->media_addr);
            $header            = [
                "content-type:multipart/form-data",
            ];
            $res               = $this->httpsRequest($url, $data, $header, true);
            if ($res[1] == 200) {
                $rt = $this->fromXml($res[0]);
                if ($rt['return_code'] != 'SUCCESS' && $rt['result_code'] != 'SUCCESS') {
                    throw new WxException(0, $rt['return_msg']);
                }
                if ($this->checkSign($rt)) {
                    return [
                        'media_id' => $rt['media_id'],
                    ];
                }
            }
            throw new WxException(30002);
        }

        public function saveImg()
        {
            $images = Request::file('media'); //1、使用laravel 自帶的request類來獲取一下檔案
            if (!$images) {
                \Log::info('saveImg' . microtime(true));
                throw new WxException(0, '至少上傳一張圖片');
            }
            $uploadMediaAddr = Config::get('api.wechatConfig.uploadMediaAddr'); //2、定義圖片上傳路徑
            $imagesName      = $images->getClientOriginalName(); //3、獲取上傳圖片的檔名
            $extension       = $images->getClientOriginalExtension(); //4、獲取上傳圖片的字尾名
            if (in_array($extension, ['jpeg', 'jpg', 'bmp', 'png'])) {
                $newImagesName = md5(microtime()) . random_int(10000, 50000) . "." . $extension;//5、重新命名上傳檔名字
                $res           = $images->move($uploadMediaAddr, $newImagesName); //6、使用move方法移動檔案.
                return $this->media_addr = $res->getRealPath();
            }
            throw new \Exception(10002);
        }
    }

注：這個介面需要證書，curl設定好，不然返回為空（設定如下圖）