From a247bf678e90a43ef428460eca1fc6c6c8352fed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?David=20Mudr=C3=A1k?= <david@moodle.com>
Date: Tue, 22 Aug 2017 23:50:49 +0200
Subject: [PATCH] MDL-59645 oauth1: Improve reporting of token errors

Provide a more meaningful error message and debuginfo allowing to
diagnose what is going on. In case of flickr, this is typically thrown
when flickr API responses with their "bad, bad panda" HTML page instead
of the expected reply.
---
 lang/en/error.php | 2 ++
 lib/oauthlib.php  | 7 ++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/lang/en/error.php b/lang/en/error.php
index 2c1e61e3ab4..1c4898573de 100644
--- a/lang/en/error.php
+++ b/lang/en/error.php
@@ -448,6 +448,8 @@ $string['notlocalisederrormessage'] = '{$a}';
 $string['notmemberofgroup'] = 'You are not a member of this course group';
 $string['notownerofkey'] = 'You are not owner of this key';
 $string['nousers'] = 'No such user!';
+$string['oauth1accesstoken'] = 'OAuth 1.0 error: We did not obtain the access token.';
+$string['oauth1requesttoken'] = 'OAuth 1.0 error: We did not obtain the request token - the service provider may be temporarily down.';
 $string['onlyadmins'] = 'Only administrators can do that';
 $string['onlyeditingteachers'] = 'Only editing teachers can do that';
 $string['onlyeditown'] = 'You can only edit your own information';
diff --git a/lib/oauthlib.php b/lib/oauthlib.php
index a8181224850..7b7262f681d 100644
--- a/lib/oauthlib.php
+++ b/lib/oauthlib.php
@@ -232,7 +232,7 @@ class oauth_helper {
         //     oauth_token_secret
         $result = $this->parse_result($content);
         if (empty($result['oauth_token'])) {
-            throw new moodle_exception('Error while requesting an oauth token');
+            throw new moodle_exception('oauth1requesttoken', 'core_error', '', null, $content);
         }
         // Build oauth authorize url.
         $result['authorize_url'] = $this->authorize_url . '?oauth_token='.$result['oauth_token'];
@@ -265,6 +265,11 @@ class oauth_helper {
         unset($params['oauth_callback']);
         $content = $this->http->post($this->access_token_api, $params, $this->http_options);
         $keys = $this->parse_result($content);
+
+        if (empty($keys['oauth_token']) || empty($keys['oauth_token_secret'])) {
+            throw new moodle_exception('oauth1accesstoken', 'core_error', '', null, $content);
+        }
+
         $this->set_access_token($keys['oauth_token'], $keys['oauth_token_secret']);
         return $keys;
     }