一、概述和通过config接口注入权限验证配置

由于微信的临时素材（如：录音文件）上传到微信服务器上，微信后台保存时间为3天。而我们需要长期保存，我们需要把资源从微信服务器转存到自己服务器，或者阿里云OSS/七牛云。

通过config接口注入权限验证配置：

/** * 微信JS-SDK权限验证配置 *  * @return array */public function getSignPackage() {    (new SignPackage())->goCheck();    $url = input('get.url');    $jsapiTicket = $this->getJsApiTicket();    $nonceStr = getRandChar(16);    $timestamp = time();    $signature = $this->getSignature($jsapiTicket,$nonceStr,$timestamp,$url);    $signPackage = array(        "appId"     => config('wx.g_app_id'),        "nonceStr"  => $nonceStr,        "timestamp" => $timestamp,        "signature" => $signature,        'expire_id' => config('setting.access_token_expire_in'),        'url'       => $url    );    return $signPackage;}/** * 获取签名 *  * @param $jsapiTicket * @param $nonceStr * @param $timestamp * @param $url * @return string */private  function getSignature($jsapiTicket,$nonceStr,$timestamp,$url){    // 这里参数的顺序要按照 key 值 ASCII 码升序排序    $string = "jsapi_ticket=$jsapiTicket&noncestr=$nonceStr&timestamp=$timestamp&url=$url";    $signature = sha1($string);    return $signature;}/** * 获取临时票据 * { * "errcode": 0, * "errmsg": "ok", * "ticket": "kgt8ON7yVITDhtdwci0qeS9ULEKIkoU74AB_VMOQrWUhbW12MQht4FiX4qLA9Z5puKabs96SARo5f1bylEvwXw", * "expires_in": 7200 * } * @return mixed * @throws Exception * @throws ParameterException */private function getJsApiTicket() {    $access_token = $this->getAccessToken();    $wxJSapiTicketUrl = sprintf(config('wx.jsapi_ticket'), $access_token);    $result = curl_get($wxJSapiTicketUrl);    $wxResult = json_decode($result, true);    if (empty($wxResult)) {        throw new Exception('微信内部错误');    }else if ($wxResult['errmsg'] != 'ok'){        throw new ParameterException([            'errorCode' => $wxResult['errcode'],            'msg' => $wxResult['errmsg']        ]);    };    return $wxResult['ticket'];}

二、获取media_id

三、根据media_id下载录音文件

/** * 获取访问微信接口的access_token *  * @return mixed */public function getAccessToken(){    $redis = Cache::store('redis');    $wx_access_token = $redis->get('wx_access_token');    if (!$wx_access_token){        $access_token = $this->getWXAccessToken();    }else{        $access_token = $wx_access_token;    }    return $access_token;}

/**     * 根据URL地址，下载文件     *     * @param $url     * @param $savePath     */    public function downAndSaveFile($url,$savePath)    {        ob_start();        readfile($url);        $img  = ob_get_contents();        ob_end_clean();        $size = strlen($img);        $fp = fopen($savePath, 'a');        fwrite($fp, $img);        fclose($fp);    }

四、FFmpeg将amr格式音频文件转换未mp3格式

/** * 将amr格式转换成mp3格式 * * @param $amr * @param $prefix_filename * @return mixed */public function amrTransCodingMp3($amr, $prefix_filename){    $msgId = $prefix_filename;    $mp3 = $msgId.'.mp3';    $dir = $_SERVER['DOCUMENT_ROOT'].'/static/audio/';    exec("ffmpeg -y -i ".$dir.$amr." ".$dir.$mp3);    return $mp3;}

五、将转码后MP3文件上传至OSS

/** * 上传指定的本地文件内容 * * @param OssClient $ossClient OSSClient实例 * @param string $bucket 存储空间名称 * @param string $object 名字 * @return mixed */function uploadFile($ossClient, $bucket, $object){    $filePath = $_SERVER['DOCUMENT_ROOT'].'/static/audio/'.$object;    try{        $res = $ossClient->uploadFile($bucket, $object, $filePath);        return $res;    } catch(OssException $e) {        return [            'error' => 'FAILED',            'msg'   => $e->getMessage()        ];    }}

注：

坑一：貌似服务端只有JAVA的，其实通过PHP-SDK也是可以通过上传文件来上传音频文件。

坑二：

六、删除本地文件

由于我把微信音频文件存到阿里云OSS，所以将从微信服务器下载的amr和转码的mp3两个音频文件删除。

/** * 删除本地音频文件 * * @param $filename * @return bool * @throws ParameterException */public function deleteDownloadFile($filename){    $filename = $_SERVER['DOCUMENT_ROOT'].'/static/audio/'.$filename;    if (!unlink($filename))    {        throw new ParameterException([            'msg' => "Error deleting $filename"        ]);    }    else    {        return true;    }}

七、测试样例

微信录音时长最多为60s,经测试H5端录音60s语音后，后台下载，转码后如下图：

然后将mp3文件上传OSS后返回给客户端如下：

{    "server": "AliyunOSS",    "date": "Mon, 09 Oct 2017 05:52:28 GMT",    "content-length": "0",    "connection": "keep-alive",    "x-oss-request-id": "59DB0E9BE8DFE89CE466195A",    "etag": "\"A6D50FD012FE2C6AA03EBF38CE23BEEB\"",    "x-oss-hash-crc64ecma": "8903374940512099110",    "content-md5": "ptUP0BL+LGqgPr84ziO+6w==",    "x-oss-server-time": "243",    "info": {        "url": "http://xds-test.oss-cn-beijing.aliyuncs.com/wx_download_2017100913522559db0e99d3420.mp3",        "content_type": null,        "http_code": 200,        "header_size": 335,        "request_size": 472,        "filetime": -1,        "ssl_verify_result": 0,        "redirect_count": 0,        "total_time": 0.250512,        "namelookup_time": 0.001418,        "connect_time": 0.004533,        "pretransfer_time": 0.004535,        "size_upload": 60309,        "size_download": 0,        "speed_download": 0,        "speed_upload": 240742,        "download_content_length": 0,        "upload_content_length": 60309,        "starttransfer_time": 0.007707,        "redirect_time": 0,        "redirect_url": "",        "primary_ip": "59.110.185.134",        "certinfo": [],        "method": "PUT"    },    "oss-request-url": "http://xds-test.oss-cn-beijing.aliyuncs.com/wx_download_2017100913522559db0e99d3420.mp3",    "oss-redirects": 0,    "oss-stringtosign": "PUT\n\naudio/mpeg\nMon, 09 Oct 2017 05:52:27 GMT\n/xds-test/wx_download_2017100913522559db0e99d3420.mp3",    "oss-requestheaders": {        "Accept-Encoding": "",        "Content-Type": "audio/mpeg",        "Date": "Mon, 09 Oct 2017 05:52:27 GMT",        "Host": "xds-test.oss-cn-beijing.aliyuncs.com",        "Authorization": "OSS LTAIiKza8Qoz9q4A:PB8WBZp75iaN/pvpbIewFs3Rn08="    },    "body": false,    "process_time": "2.2304130s"}

从返回process_time来看，从客户端请求到最后返回给客户端，60s音频后台大概需要处理2.3秒左右（根据服务器配置而不同）。

完

参考资料如下：