PHP 구글 로그인 연동

구글 API 클라이언트 라이브러리를 사용하는 예제

<?php

require_once __DIR__ . '/vendor/autoload.php'; // Google API 클라이언트 라이브러리 로드

session_start();

// Google API 인증 정보를 저장하는 파일 경로
$credentialsPath = __DIR__ . '/google-api-credentials.json';

// Google_Client 객체 생성
$client = new Google_Client();
$client->setApplicationName('Google Login Example');
$client->setScopes([
    'https://www.googleapis.com/auth/userinfo.email',
    'https://www.googleapis.com/auth/userinfo.profile'
]);

// Google API 인증 정보를 파일에서 로드
if (file_exists($credentialsPath)) {
    $accessToken = json_decode(file_get_contents($credentialsPath), true);
    $client->setAccessToken($accessToken);
}

// 로그인된 사용자의 정보 가져오기
if ($client->getAccessToken()) {
    $oauth2 = new Google_Service_Oauth2($client);
    $userInfo = $oauth2->userinfo->get();

    // 사용자 정보 출력
    echo '<p>Hello, ' . $userInfo->name . '!</p>';
    echo '<p>Your email address is: ' . $userInfo->email . '</p>';

    // 로그아웃 버튼 생성
    echo '<a href="?logout">Logout</a>';

    // 로그아웃 요청 처리
    if (isset($_GET['logout'])) {
        unset($_SESSION['access_token']);
        $client->revokeToken();
        header('Location: ' . filter_var($_SERVER['PHP_SELF'], FILTER_SANITIZE_URL));
    }
} else {
    // 로그인 버튼 생성
    $authUrl = $client->createAuthUrl();
    echo '<a href="' . $authUrl . '">Login</a>';
}

 

구글 인증 서버와 직접 통신하는 예제

<?php
session_start();
$google_redirect_url = 'http://localhost/google-login-api/';
$client_id = 'YOUR_CLIENT_ID';
$client_secret = 'YOUR_CLIENT_SECRET';
$scope = 'https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/userinfo.profile';

function curl($url,$parameters){
    $ch = curl_init();
    curl_setopt($ch,CURLOPT_URL,$url);
    curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
    curl_setopt($ch,CURLOPT_SSL_VERIFYPEER,false);
    curl_setopt($ch,CURLOPT_POSTFIELDS,$parameters);
    $data = curl_exec($ch);
    return $data;
}

function getCallbackUrl(){
    global $google_redirect_url;
    return urlencode($google_redirect_url.'index.php?google=callback');
}

function getLoginUrl(){
    global $client_id,$scope;
    return "https://accounts.google.com/o/oauth2/auth?response_type=code&redirect_uri=".getCallbackUrl()."&client_id=".$client_id."&scope=".$scope;
}

function getAccessToken(){
    global $client_id,$client_secret;
    
    if(isset($_GET['code'])){
        // get access token from authorization code
        $url = "https://accounts.google.com/o/oauth2/token";
        $parameters="code=".$_GET['code']."&client_id=".$client_id."&client_secret=".$client_secret."&redirect_uri=".getCallbackUrl()."&grant_type=authorization_code";
        return json_decode(curl($url,$parameters),true)['access_token'];
        
    }else if(isset($_SESSION['access_token'])){
        // get access token from session
        return $_SESSION['access_token'];
        
    }else{
        // redirect to login url
        header("Location: ".getLoginUrl());
        exit;
        
    }
}

function getUserInfo(){
    
   // get user info from google api
   $url="https://www.googleapis.com/oauth2/v1/userinfo?alt=json&access_token=".getAccessToken();
   return json_decode(file_get_contents($url),true);

}

if(isset($_GET['google']) && $_GET['google']=='callback'){
    
   // store access token in session
   $_SESSION['access_token']=getAccessToken();

   // redirect to index page
   header("Location: ".$google_redirect_url."index.php");
   
}else{
    
   // print user info
   print_r(getUserInfo());
   
}