updates for sample github app

github.php

@@ -13,24 +13,11 @@ $tokenURL = 'https://github.com/login/oauth/access_token';
 $apiURLBase = 'https://api.github.com/';
 
 // The URL for this script, used as the redirect URL
-$baseURL = 'https://' . $_SERVER['SERVER_NAME']
-    . $_SERVER['PHP_SELF'];
+$baseURL = 'https://' . $_SERVER['SERVER_NAME'] . $_SERVER['PHP_SELF'];
 
 // Start a session so we have a place to store things between redirects
 session_start();
 
-// If there is an access token in the session, the user is logged in
-if(!isset($_GET['action'])) {
-  if(!empty($_SESSION['access_token'])) {
-    echo '<h3>Logged In</h3>';
-    echo '<p><a href="?action=repos">View Repos</a></p>';
-    echo '<p><a href="?action=logout">Log Out</a></p>';
-  } else {
-    echo '<h3>Not logged in</h3>';
-    echo '<p><a href="?action=login">Log In</a></p>';
-  }
-  die();
-}
 
 // Start the login process by sending the user to Github's authorization page
 if(isset($_GET['action']) && $_GET['action'] == 'login') {
@@ -40,6 +27,7 @@ if(isset($_GET['action']) && $_GET['action'] == 'login') {
   $_SESSION['state'] = bin2hex(random_bytes(16));
 
   $params = array(
+    'response_type' => 'code',
     'client_id' => $githubClientID,
     'redirect_uri' => $baseURL,
     'scope' => 'user public_repo',
@@ -65,7 +53,7 @@ if(isset($_GET['code'])) {
     die();
   }
 
-  // Exchange the auth code for a token
+  // Exchange the auth code for an access token
   $token = apiRequest($tokenURL, array(
     'grant_type' => 'authorization_code',
     'client_id' => $githubClientID,
@@ -96,6 +84,19 @@ if(isset($_GET['action']) && $_GET['action'] == 'repos') {
   die();
 }
 
+// If there is an access token in the session, the user is logged in
+if(!isset($_GET['action'])) {
+  if(!empty($_SESSION['access_token'])) {
+    echo '<h3>Logged In</h3>';
+    echo '<p><a href="?action=repos">View Repos</a></p>';
+    echo '<p><a href="?action=logout">Log Out</a></p>';
+  } else {
+    echo '<h3>Not logged in</h3>';
+    echo '<p><a href="?action=login">Log In</a></p>';
+  }
+  die();
+}
+
 
 // This helper function will make API requests to GitHub, setting
 // the appropriate headers GitHub expects, and decoding the JSON response
@@ -107,7 +108,7 @@ function apiRequest($url, $post=FALSE, $headers=array()) {
     curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($post));
 
   $headers = [
-    'Accept: application/vnd.github.v3+json',
+    'Accept: application/vnd.github.v3+json, application/json',
     'User-Agent: https://example-app.com/'
   ];