Improve GitHub oauth email discovery

app/controllers/api/account.php

@@ -566,6 +566,10 @@ App::get('/v1/account/sessions/oauth2/:provider/redirect')
             $name = $oauth2->getUserName($accessToken);
             $email = $oauth2->getUserEmail($accessToken);
 
+            if(empty($email)) {
+                throw new Exception(Exception::USER_UNAUTHORIZED, 'OAuth provider failed to return email.');
+            }
+
             /**
              * Is verified is not used yet, since we don't know after an accout is created anymore if it was verified or not.
              */

src/Appwrite/Auth/OAuth2/Github.php

@@ -183,13 +183,27 @@ class Github extends OAuth2
             $emails = $this->request('GET', 'https://api.github.com/user/emails', ['Authorization: token ' . \urlencode($accessToken)]);
 
             $emails = \json_decode($emails, true);
+
+            $verifiedEmail = null;
+            $primaryEmail = null;
+
             foreach ($emails as $email) {
                 if (isset($email['verified']) && $email['verified'] === true) {
-                    $this->user['email'] = $email['email'];
-                    $this->user['verified'] = $email['verified'];
-                    break;
+                    $verifiedEmail = $email;
+
+                    if (isset($email['primary']) && $email['primary'] === true) {
+                        $primaryEmail = $email;
+                    }
                 }
             }
+
+            if(!empty($primaryEmail)) {
+                $this->user['email'] = $primaryEmail['email'];
+                $this->user['verified'] = $primaryEmail['verified'];
+            } else if(!empty($verifiedEmail)) {
+                $this->user['email'] = $verifiedEmail['email'];
+                $this->user['verified'] = $verifiedEmail['verified'];
+            }
         }
 
         return $this->user;