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내 회사 페이지에 일부 콘텐츠를 게시하기 위해 Linkedin API를 사용하려고하는데 아주 이상한 오류가 있습니다. 여기 내가 지금까지 한 일이 있습니다. https://mywebsite.com/linkedin/demo.php «인증 과정에서 오류가 발생했습니다»»Linkedin API를 사용하여
- 의 OAuth : 모든
첫째, 나는 는 다음과 같은 매개 변수를 사용하여 응용 프로그램을 등록 된 모든 매개 변수를
을 확인
가 그럼 난 내 링크드 인 폴더에 넣어 다음 파일을
:auth.php<?php
session_start();
$config['base_url'] = 'http://mywebsite.com/linkedin/auth.php';
$config['callback_url'] = 'http://mywebsite.com/linkedin/demo.php';
$config['linkedin_access'] = '************';
$config['linkedin_secret'] = '************';
include_once "linkedin.php";
$linkedin = new LinkedIn($config['linkedin_access'], $config['linkedin_secret'], $config['callback_url']);
$linkedin->getRequestToken();
$_SESSION['requestToken'] = serialize($linkedin->request_token);
header("Location: " . $linkedin->generateAuthorizeUrl());;
?>
demo.php
<?php
session_start();
$config['base_url'] = 'http://mywebsite.com/linkedin/auth.php';
$config['callback_url'] = 'http://mywebsite.com/linkedin/demo.php';
$config['linkedin_access'] = '************';
$config['linkedin_secret'] = '************';
include_once "linkedin.php";
$linkedin = new LinkedIn($config['linkedin_access'], $config['linkedin_secret'], $config['callback_url']);
if (isset($_REQUEST['oauth_verifier'])){
$_SESSION['oauth_verifier'] = $_REQUEST['oauth_verifier'];
$linkedin->request_token = unserialize($_SESSION['requestToken']);
$linkedin->oauth_verifier = $_SESSION['oauth_verifier'];
$linkedin->getAccessToken($_REQUEST['oauth_verifier']);
$_SESSION['oauth_access_token'] = serialize($linkedin->access_token);
header("Location: " . $config['callback_url']);
exit;
} else{
$linkedin->request_token = unserialize($_SESSION['requestToken']);
$linkedin->oauth_verifier = $_SESSION['oauth_verifier'];
$linkedin->access_token = unserialize($_SESSION['oauth_access_token']);
}
$xml_response = $linkedin->getProfile("~:(id,first-name,last-name,headline,picture-url)");
echo '<pre>';
echo 'My Profile Info';
echo $xml_response;
echo '<br />';
echo '</pre>';
$search_response = $linkedin->search("?company-name=facebook&count=10");
echo $search_response;
$xml = simplexml_load_string($search_response);
echo '<pre>';
echo 'Look people who worked in facebook';
print_r($xml);
echo '</pre>';
?>
나는 또한 OAuth.php에게 내가 쉽게 온라인으로 볼 파일을 linkedin.php 등을 넣어
Linkedin.php
<?php
require_once("OAuth.php");
class LinkedIn {
public $base_url = "http://api.linkedin.com";
public $secure_base_url = "https://api.linkedin.com";
public $oauth_callback = "oob";
public $consumer;
public $request_token;
public $access_token;
public $oauth_verifier;
public $signature_method;
public $request_token_path;
public $access_token_path;
public $authorize_path;
public $debug = false;
function __construct($consumer_key, $consumer_secret, $oauth_callback = NULL) {
if($oauth_callback) {
$this->oauth_callback = $oauth_callback;
}
$this->consumer = new OAuthConsumer($consumer_key, $consumer_secret, $this->oauth_callback);
$this->signature_method = new OAuthSignatureMethod_HMAC_SHA1();
$this->request_token_path = $this->secure_base_url . "/uas/oauth/requestToken";
$this->access_token_path = $this->secure_base_url . "/uas/oauth/accessToken";
$this->authorize_path = $this->secure_base_url . "/uas/oauth/authorize";
}
function getRequestToken() {
$consumer = $this->consumer;
$request = OAuthRequest::from_consumer_and_token($consumer, NULL, "GET", $this->request_token_path);
$request->set_parameter("oauth_callback", $this->oauth_callback);
$request->sign_request($this->signature_method, $consumer, NULL);
$headers = Array();
$url = $request->to_url();
$response = $this->httpRequest($url, $headers, "GET");
parse_str($response, $response_params);
$this->request_token = new OAuthConsumer($response_params['oauth_token'], $response_params['oauth_token_secret'], 1);
}
function generateAuthorizeUrl() {
$consumer = $this->consumer;
$request_token = $this->request_token;
return $this->authorize_path . "?oauth_token=" . $request_token->key;
}
function getAccessToken($oauth_verifier) {
$request = OAuthRequest::from_consumer_and_token($this->consumer, $this->request_token, "GET", $this->access_token_path);
$request->set_parameter("oauth_verifier", $oauth_verifier);
$request->sign_request($this->signature_method, $this->consumer, $this->request_token);
$headers = Array();
$url = $request->to_url();
$response = $this->httpRequest($url, $headers, "GET");
parse_str($response, $response_params);
if($debug) {
echo $response . "\n";
}
$this->access_token = new OAuthConsumer($response_params['oauth_token'], $response_params['oauth_token_secret'], 1);
}
function getProfile($resource = "~") {
$profile_url = $this->base_url . "/v1/people/" . $resource;
$request = OAuthRequest::from_consumer_and_token($this->consumer, $this->access_token, "GET", $profile_url);
$request->sign_request($this->signature_method, $this->consumer, $this->access_token);
$auth_header = $request->to_header("https://api.linkedin.com");
if ($debug) {
echo $auth_header;
}
// $response will now hold the XML document
$response = $this->httpRequest($profile_url, $auth_header, "GET");
return $response;
}
function setStatus($status) {
$status_url = $this->base_url . "/v1/people/~/current-status";
echo "Setting status...\n";
$xml = "<current-status>" . htmlspecialchars($status, ENT_NOQUOTES, "UTF-8") . "</current-status>";
echo $xml . "\n";
$request = OAuthRequest::from_consumer_and_token($this->consumer, $this->access_token, "PUT", $status_url);
$request->sign_request($this->signature_method, $this->consumer, $this->access_token);
$auth_header = $request->to_header("https://api.linkedin.com");
if ($debug) {
echo $auth_header . "\n";
}
$response = $this->httpRequest($profile_url, $auth_header, "GET");
return $response;
}
function search($parameters) {
$search_url = $this->base_url . "/v1/people/" . $parameters;
echo "Performing search for: " . $parameters . "\n";
$request = OAuthRequest::from_consumer_and_token($this->consumer, $this->access_token, "GET", $search_url);
$request->sign_request($this->signature_method, $this->consumer, $this->access_token);
$auth_header = $request->to_header("https://api.linkedin.com");
if ($debug) {
echo $request->get_signature_base_string() . "\n";
echo $auth_header . "\n";
}
$response = $this->httpRequest($search_url, $auth_header, "GET");
return $response;
}
function httpRequest($url, $auth_header, $method, $body = NULL) {
if (!$method) {
$method = "GET";
};
$curl = curl_init();
curl_setopt($curl, CURLOPT_URL, $url);
curl_setopt($curl, CURLOPT_HEADER, 0);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($curl, CURLOPT_HTTPHEADER, array($auth_header)); // Set the headers.
if ($body) {
curl_setopt($curl, CURLOPT_POST, 1);
curl_setopt($curl, CURLOPT_POSTFIELDS, $body);
curl_setopt($curl, CURLOPT_CUSTOMREQUEST, $method);
curl_setopt($curl, CURLOPT_HTTPHEADER, array($auth_header, "Content-Type: text/xml;charset=utf-8"));
}
$data = curl_exec($curl);
if ($this->debug) {
echo $data . "\n";
}
curl_close($curl);
return $data;
}
}
OAuth.php
<?php
class OAuthConsumer {
public $key;
public $secret;
function __construct($key, $secret, $callback_url=NULL) {
$this->key = $key;
$this->secret = $secret;
$this->callback_url = $callback_url;
}
function __toString() {
return "OAuthConsumer[key=$this->key,secret=$this->secret]";
}
}
class OAuthToken {
public $key;
public $secret;
function __construct($key, $secret) {
$this->key = $key;
$this->secret = $secret;
}
function to_string() {
return "oauth_token=" .
OAuthUtil::urlencode_rfc3986($this->key) .
"&oauth_token_secret=" .
OAuthUtil::urlencode_rfc3986($this->secret);
}
function __toString() {
return $this->to_string();
}
}
abstract class OAuthSignatureMethod {
abstract public function get_name();
abstract public function build_signature($request, $consumer, $token);
public function check_signature($request, $consumer, $token, $signature) {
$built = $this->build_signature($request, $consumer, $token);
return $built == $signature;
}
}
class OAuthSignatureMethod_HMAC_SHA1 extends OAuthSignatureMethod {
function get_name() {
return "HMAC-SHA1";
}
public function build_signature($request, $consumer, $token) {
$base_string = $request->get_signature_base_string();
$request->base_string = $base_string;
$key_parts = array(
$consumer->secret,
($token) ? $token->secret : ""
);
$key_parts = OAuthUtil::urlencode_rfc3986($key_parts);
$key = implode('&', $key_parts);
return base64_encode(hash_hmac('sha1', $base_string, $key, true));
}
}
class OAuthSignatureMethod_PLAINTEXT extends OAuthSignatureMethod {
public function get_name() {
return "PLAINTEXT";
}
public function build_signature($request, $consumer, $token) {
$key_parts = array($consumer->secret,($token) ? $token->secret : "");
$key_parts = OAuthUtil::urlencode_rfc3986($key_parts);
$key = implode('&', $key_parts);
$request->base_string = $key;
return $key;
}
}
abstract class OAuthSignatureMethod_RSA_SHA1 extends OAuthSignatureMethod {
public function get_name() { return "RSA-SHA1";}
protected abstract function fetch_public_cert(&$request);
public function build_signature($request, $consumer, $token) {
$base_string = $request->get_signature_base_string();
$request->base_string = $base_string;
$cert = $this->fetch_private_cert($request);
$privatekeyid = openssl_get_privatekey($cert);
$ok = openssl_sign($base_string, $signature, $privatekeyid);
openssl_free_key($privatekeyid);
return base64_encode($signature);
}
public function check_signature($request, $consumer, $token, $signature) {
$decoded_sig = base64_decode($signature);
$base_string = $request->get_signature_base_string();
$cert = $this->fetch_public_cert($request);
$publickeyid = openssl_get_publickey($cert);
$ok = openssl_verify($base_string, $decoded_sig, $publickeyid);
openssl_free_key($publickeyid);
return $ok == 1;
}
}
class OAuthRequest {
private $parameters;
private $http_method;
private $http_url;
// for debug purposes
public $base_string;
public static $version = '1.0';
public static $POST_INPUT = 'php://input';
function __construct($http_method, $http_url, $parameters=NULL) {
@$parameters or $parameters = array();
$parameters = array_merge(OAuthUtil::parse_parameters(parse_url($http_url, PHP_URL_QUERY)), $parameters);
$this->parameters = $parameters;
$this->http_method = $http_method;
$this->http_url = $http_url;
}
public static function from_request($http_method=NULL, $http_url=NULL, $parameters=NULL) {
$scheme = (!isset($_SERVER['HTTPS']) || $_SERVER['HTTPS'] != "on")
? 'http'
: 'https';
@$http_url or $http_url = $scheme .
'://' . $_SERVER['HTTP_HOST'] .
':' .
$_SERVER['SERVER_PORT'] .
$_SERVER['REQUEST_URI'];
@$http_method or $http_method = $_SERVER['REQUEST_METHOD'];
if (!$parameters) {
$request_headers = OAuthUtil::get_headers();
$parameters = OAuthUtil::parse_parameters($_SERVER['QUERY_STRING']);
if ($http_method == "POST"
&& @strstr($request_headers["Content-Type"],
"application/x-www-form-urlencoded")
) {
$post_data = OAuthUtil::parse_parameters(
file_get_contents(self::$POST_INPUT)
);
$parameters = array_merge($parameters, $post_data);
}
if (@substr($request_headers['Authorization'], 0, 6) == "OAuth ") {
$header_parameters = OAuthUtil::split_header(
$request_headers['Authorization']
);
$parameters = array_merge($parameters, $header_parameters);
}
}
return new OAuthRequest($http_method, $http_url, $parameters);
}
public static function from_consumer_and_token($consumer, $token, $http_method, $http_url, $parameters=NULL) {
@$parameters or $parameters = array();
$defaults = array("oauth_version" => OAuthRequest::$version,
//"oauth_nonce" => OAuthRequest::generate_nonce(),
"oauth_timestamp" => OAuthRequest::generate_timestamp(),
"oauth_consumer_key" => $consumer->key);
if ($token)
$defaults['oauth_token'] = $token->key;
$parameters = array_merge($defaults, $parameters);
return new OAuthRequest($http_method, $http_url, $parameters);
}
public function set_parameter($name, $value, $allow_duplicates = true) {
if ($allow_duplicates && isset($this->parameters[$name])) {
if (is_scalar($this->parameters[$name])) {
$this->parameters[$name] = array($this->parameters[$name]);
}
$this->parameters[$name][] = $value;
} else {
$this->parameters[$name] = $value;
}
}
public function get_parameter($name) {
return isset($this->parameters[$name]) ? $this->parameters[$name] : null;
}
public function get_parameters() {
return $this->parameters;
}
public function unset_parameter($name) {
unset($this->parameters[$name]);
}
public function get_signable_parameters() {
$params = $this->parameters;
if (isset($params['oauth_signature'])) {
unset($params['oauth_signature']);
}
return OAuthUtil::build_http_query($params);
}
public function get_signature_base_string() {
$parts = array(
$this->get_normalized_http_method(),
$this->get_normalized_http_url(),
$this->get_signable_parameters()
);
$parts = OAuthUtil::urlencode_rfc3986($parts);
return implode('&', $parts);
}
public function get_normalized_http_method() {
return strtoupper($this->http_method);
}
public function get_normalized_http_url() {
$parts = parse_url($this->http_url);
$port = @$parts['port'];
$scheme = $parts['scheme'];
$host = $parts['host'];
$path = @$parts['path'];
$port or $port = ($scheme == 'https') ? '443' : '80';
if (($scheme == 'https' && $port != '443')
|| ($scheme == 'http' && $port != '80')) {
$host = "$host:$port";
}
return "$scheme://$host$path";
}
public function to_url() {
$post_data = $this->to_postdata();
$out = $this->get_normalized_http_url();
if ($post_data) {
$out .= '?'.$post_data;
}
return $out;
}
public function to_postdata() {
return OAuthUtil::build_http_query($this->parameters);
}
public function to_header($realm=null) {
if($realm)
$out = 'Authorization: OAuth realm="' . OAuthUtil::urlencode_rfc3986($realm) . '"';
else
$out = 'Authorization: OAuth';
$total = array();
foreach ($this->parameters as $k => $v) {
if (substr($k, 0, 5) != "oauth") continue;
if (is_array($v)) {
throw new OAuthException('Arrays not supported in headers');
}
$out .= ',' .
OAuthUtil::urlencode_rfc3986($k) .
'="' .
OAuthUtil::urlencode_rfc3986($v) .
'"';
}
return $out;
}
public function __toString() {
return $this->to_url();
}
public function sign_request($signature_method, $consumer, $token) {
$this->set_parameter(
"oauth_signature_method",
$signature_method->get_name(),
false
);
$signature = $this->build_signature($signature_method, $consumer, $token);
$this->set_parameter("oauth_signature", $signature, false);
}
public function build_signature($signature_method, $consumer, $token) {
$signature = $signature_method->build_signature($this, $consumer, $token);
return $signature;
}
private static function generate_timestamp() {
return time();
}
private static function generate_nonce() {
$mt = microtime();
$rand = mt_rand();
return md5($mt . $rand); // md5s look nicer than numbers
}
}
class OAuthServer {
protected $timestamp_threshold = 300; // in seconds, five minutes
protected $version = '1.0'; // hi blaine
protected $signature_methods = array();
protected $data_store;
function __construct($data_store) {
$this->data_store = $data_store;
}
public function add_signature_method($signature_method) {
$this->signature_methods[$signature_method->get_name()] =
$signature_method;
}
public function fetch_request_token(&$request) {
$this->get_version($request);
$consumer = $this->get_consumer($request);
$token = NULL;
$this->check_signature($request, $consumer, $token);
$callback = $request->get_parameter('oauth_callback');
$new_token = $this->data_store->new_request_token($consumer, $callback);
return $new_token;
}
public function fetch_access_token(&$request) {
$this->get_version($request);
$consumer = $this->get_consumer($request);
// requires authorized request token
$token = $this->get_token($request, $consumer, "request");
$this->check_signature($request, $consumer, $token);
// Rev A change
$verifier = $request->get_parameter('oauth_verifier');
$new_token = $this->data_store->new_access_token($token, $consumer, $verifier);
return $new_token;
}
public function verify_request(&$request) {
$this->get_version($request);
$consumer = $this->get_consumer($request);
$token = $this->get_token($request, $consumer, "access");
$this->check_signature($request, $consumer, $token);
return array($consumer, $token);
}
private function get_version(&$request) {
$version = $request->get_parameter("oauth_version");
if (!$version) {
// Service Providers MUST assume the protocol version to be 1.0 if this parameter is not present.
// Chapter 7.0 ("Accessing Protected Ressources")
$version = '1.0';
}
if ($version !== $this->version) {
throw new OAuthException("OAuth version '$version' not supported");
}
return $version;
}
private function get_signature_method(&$request) {
$signature_method =
@$request->get_parameter("oauth_signature_method");
if (!$signature_method) {
// According to chapter 7 ("Accessing Protected Ressources") the signature-method
// parameter is required, and we can't just fallback to PLAINTEXT
throw new OAuthException('No signature method parameter. This parameter is required');
}
if (!in_array($signature_method,
array_keys($this->signature_methods))) {
throw new OAuthException(
"Signature method '$signature_method' not supported " .
"try one of the following: " .
implode(", ", array_keys($this->signature_methods))
);
}
return $this->signature_methods[$signature_method];
}
private function get_consumer(&$request) {
$consumer_key = @$request->get_parameter("oauth_consumer_key");
if (!$consumer_key) {
throw new OAuthException("Invalid consumer key");
}
$consumer = $this->data_store->lookup_consumer($consumer_key);
if (!$consumer) {
throw new OAuthException("Invalid consumer");
}
return $consumer;
}
private function get_token(&$request, $consumer, $token_type="access") {
$token_field = @$request->get_parameter('oauth_token');
$token = $this->data_store->lookup_token(
$consumer, $token_type, $token_field
);
if (!$token) {
throw new OAuthException("Invalid $token_type token: $token_field");
}
return $token;
}
private function check_signature(&$request, $consumer, $token) {
$timestamp = @$request->get_parameter('oauth_timestamp');
$nonce = @$request->get_parameter('oauth_nonce');
$this->check_timestamp($timestamp);
$this->check_nonce($consumer, $token, $nonce, $timestamp);
$signature_method = $this->get_signature_method($request);
$signature = $request->get_parameter('oauth_signature');
$valid_sig = $signature_method->check_signature(
$request,
$consumer,
$token,
$signature
);
if (!$valid_sig) {
throw new OAuthException("Invalid signature");
}
}
private function check_timestamp($timestamp) {
if(! $timestamp)
throw new OAuthException(
'Missing timestamp parameter. The parameter is required'
);
// verify that timestamp is recentish
$now = time();
if (abs($now - $timestamp) > $this->timestamp_threshold) {
throw new OAuthException(
"Expired timestamp, yours $timestamp, ours $now"
);
}
}
private function check_nonce($consumer, $token, $nonce, $timestamp) {
if(! $nonce)
throw new OAuthException(
'Missing nonce parameter. The parameter is required'
);
// verify that the nonce is uniqueish
$found = $this->data_store->lookup_nonce(
$consumer,
$token,
$nonce,
$timestamp
);
if ($found) {
throw new OAuthException("Nonce already used: $nonce");
}
}
}
class OAuthDataStore {
function lookup_consumer($consumer_key) {
// implement me
}
function lookup_token($consumer, $token_type, $token) {
// implement me
}
function lookup_nonce($consumer, $token, $nonce, $timestamp) {
// implement me
}
function new_request_token($consumer, $callback = null) {
// return a new token attached to this consumer
}
function new_access_token($token, $consumer, $verifier = null) {
}
}
class OAuthUtil {
public static function urlencode_rfc3986($input) {
if (is_array($input)) {
return array_map(array('OAuthUtil', 'urlencode_rfc3986'), $input);
} else if (is_scalar($input)) {
return str_replace(
'+',
' ',
str_replace('%7E', '~', rawurlencode($input))
);
} else {
return '';
}
}
public static function urldecode_rfc3986($string) {
return urldecode($string);
}
public static function split_header($header, $only_allow_oauth_parameters = true) {
$pattern = '/(([-_a-z]*)=("([^"]*)"|([^,]*)),?)/';
$offset = 0;
$params = array();
while (preg_match($pattern, $header, $matches, PREG_OFFSET_CAPTURE, $offset) > 0) {
$match = $matches[0];
$header_name = $matches[2][0];
$header_content = (isset($matches[5])) ? $matches[5][0] : $matches[4][0];
if (preg_match('/^oauth_/', $header_name) || !$only_allow_oauth_parameters) {
$params[$header_name] = OAuthUtil::urldecode_rfc3986($header_content);
}
$offset = $match[1] + strlen($match[0]);
}
if (isset($params['realm'])) {
unset($params['realm']);
}
return $params;
}
public static function get_headers() {
if (function_exists('apache_request_headers')) {
$headers = apache_request_headers();
$out = array();
foreach($headers AS $key => $value) {
$key = str_replace(
" ",
"-",
ucwords(strtolower(str_replace("-", " ", $key)))
);
$out[$key] = $value;
}
} else {
$out = array();
foreach ($_SERVER as $key => $value) {
if (substr($key, 0, 5) == "HTTP_") {
$key = str_replace(
" ",
"-",
ucwords(strtolower(str_replace("_", " ", substr($key, 5))))
);
$out[$key] = $value;
}
}
}
return $out;
}
public static function parse_parameters($input) {
if (!isset($input) || !$input) return array();
$pairs = explode('&', $input);
$parsed_parameters = array();
foreach ($pairs as $pair) {
$split = explode('=', $pair, 2);
$parameter = OAuthUtil::urldecode_rfc3986($split[0]);
$value = isset($split[1]) ? OAuthUtil::urldecode_rfc3986($split[1]) : '';
if (isset($parsed_parameters[$parameter])) {
// We have already recieved parameter(s) with this name, so add to the list
// of parameters with this name
if (is_scalar($parsed_parameters[$parameter])) {
// This is the first duplicate, so transform scalar (string) into an array
// so we can add the duplicates
$parsed_parameters[$parameter] = array($parsed_parameters[$parameter]);
}
$parsed_parameters[$parameter][] = $value;
} else {
$parsed_parameters[$parameter] = $value;
}
}
return $parsed_parameters;
}
public static function build_http_query($params) {
if (!$params) return '';
// Urlencode both keys and values
$keys = OAuthUtil::urlencode_rfc3986(array_keys($params));
$values = OAuthUtil::urlencode_rfc3986(array_values($params));
$params = array_combine($keys, $values);
uksort($params, 'strcmp');
$pairs = array();
foreach ($params as $parameter => $value) {
if (is_array($value)) {
natsort($value);
foreach ($value as $duplicate_value) {
$pairs[] = $parameter . '=' . $duplicate_value;
}
} else {
$pairs[] = $parameter . '=' . $value;
}
}
// For each parameter, the name is separated from the corresponding value by an '=' character (ASCII code 61)
// Each name-value pair is separated by an '&' character (ASCII code 38)
return implode('&', $pairs);
}
}
?>
하지만이 auth.php 페이지를 얻기 위해 시도 할 때, 나는이 오류를 얻을 :
오류가 인증하는 동안 발생을 시도하십시오 나중에 다시.
그리고이 페이지에서 결국 : 그래서 https://www.linkedin.com/uas/oauth/authorize?oauth_token=
, 내 측면 또는 측면에 문제가?
당신은'링크드 인에 대한 소스의 위치에 대한 구체적해야합니다 .php'와'OAuth.php' 같은 이름의 스크립트가 더 많기 때문입니다. –
@HansZ. 내가 온라인으로 찾은 linkedin.php와 OAuth.php 파일로 내 게시물을 편집했습니다. – klaus
'httpRequest' 함수에서'curl_setopt ($ curl, CURLOPT_VERBOSE, 1);'를 사용하고 실제로 getRequestToken 요청에서 토큰을 되찾았는지 확인하십시오. 콜백, 키 및/또는 비밀 설정에 불일치가있을 수 있습니다. –