Add FCM web app for testing

Author: mobizt

examples/Messaging/WebClient/auth.php

@@ -0,0 +1,84 @@
+<?php
+
+error_reporting(E_ERROR | E_PARSE);
+
+function base64url_encode($data){
+    return rtrim(strtr(base64_encode($data), '+/', '-_'), '=');
+}
+
+function generateToken($email, $privateKey){
+
+    if($email=="" || $privateKey=="")
+    return "";
+    
+    $base64UrlHeader = base64url_encode(
+        json_encode(
+            array(
+                'alg' => 'RS256',
+                'typ' => 'JWT'
+            )
+        )
+    );
+
+    $now = time();
+    $str= json_encode(
+        array(
+            "iss" => $email,
+            "sub" => $email,
+            "aud" => "https://oauth2.googleapis.com/token",
+            "iat" => $now,
+            "exp" => $now + 3600,
+            "scope" =>"https://www.googleapis.com/auth/devstorage.full_control https://www.googleapis.com/auth/datastore https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/firebase.database https://www.googleapis.com/auth/cloud-platform https://www.googleapis.com/auth/iam"
+        )
+            );
+
+    $base64UrlPayload =  base64url_encode(str_replace ("\\","",$str));
+
+    openssl_sign(
+        $base64UrlHeader.".".$base64UrlPayload,
+        $RSA256,
+        $privateKey,
+        "sha256WithRSAEncryption"
+    );
+
+    $keyRSA256 = base64url_encode($RSA256);
+    $jwt = $base64UrlHeader . "." . $base64UrlPayload . "." . $keyRSA256;
+
+    return $jwt;
+}
+
+function getAccessToken($email,$privateKey)
+{
+    if($email=="" || $privateKey=="")
+    return "";
+
+    $ch = curl_init();
+    $post = [
+        'grant_type' => 'urn:ietf:params:oauth:grant-type:jwt-bearer',
+        'assertion' => generateToken($email,$privateKey)
+    ];
+
+curl_setopt($ch, CURLOPT_URL,"https://oauth2.googleapis.com/token");
+curl_setopt($ch, CURLOPT_POST, true);
+curl_setopt($ch, CURLOPT_POSTFIELDS,$post);
+
+// Receive server response ...
+curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+$server_output = curl_exec($ch);
+$json = json_decode($server_output, true);
+curl_close($ch);
+return isset($json['access_token']) ?$json['access_token']:"";
+}
+
+$actual_link = (empty($_SERVER['HTTPS']) ? 'http' : 'https') . "://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";
+
+$parts = parse_url($actual_link);
+parse_str($parts['query'], $query);
+$email= urldecode($query['email']);
+$privateKey= str_replace(" ", "+",urldecode($query['private_key']));
+$privateKey= str_replace("BEGIN+PRIVATE+KEY", "BEGIN PRIVATE KEY",$privateKey);
+$privateKey= str_replace("END+PRIVATE+KEY", "END PRIVATE KEY",$privateKey);
+$privateKey= str_replace("\\n", "\n",$privateKey);
+echo getAccessToken($email,$privateKey);
+
+?>