From 616d68cf9481f08eae75095e2188fb7fea6d822c Mon Sep 17 00:00:00 2001
From: Zach Copley <zach@controlyourself.ca>
Date: Thu, 9 Jul 2009 00:40:12 +0000
Subject: [PATCH] Better error handling for TwitterQueueHandler

---
 lib/mail.php    | 36 ++++++++++++++++++
 lib/twitter.php | 97 ++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 116 insertions(+), 17 deletions(-)

diff --git a/lib/mail.php b/lib/mail.php
index 4e1f1dbb1d..c948f83ca9 100644
--- a/lib/mail.php
+++ b/lib/mail.php
@@ -625,3 +625,39 @@ function mail_notify_attn($user, $notice)
     common_init_locale();
     mail_to_user($user, $subject, $body);
 }
+
+/**
+ * Send a mail message to notify a user that her Twitter bridge link
+ * has stopped working, and therefore has been removed.  This can
+ * happen when the user changes her Twitter password, or otherwise
+ * revokes access.
+ *
+ * @param User $user   user whose Twitter bridge link has been removed
+ *
+ * @return boolean success flag
+ */
+
+function mail_twitter_bridge_removed($user)
+{
+    common_init_locale($user->language);
+
+    $profile = $user->getProfile();
+
+    $subject = sprintf(_('Your Twitter bridge has been disabled.'));
+
+    $body = sprintf(_("Hi, %1\$s. We're sorry to inform you that your " .
+        'link to Twitter has been disabled. Your Twitter credentials ' .
+        'have either changed (did you recently change your Twitter ' .
+        'password?) or you have otherwise revoked our access to your ' .
+        "Twitter account.\n\n" .
+        'You can re-enable your Twitter bridge by visiting your ' .
+        "Twitter settings page:\n\n\t%2\$s\n\n" .
+        "Regards,\n%3\$s\n"),
+        $profile->getBestName(),
+        common_local_url('twittersettings'),
+        common_config('site', 'name'));
+
+    common_init_locale();
+    return mail_to_user($user, $subject, $body);
+}
+
diff --git a/lib/twitter.php b/lib/twitter.php
index d5eba084b3..47af32e61f 100644
--- a/lib/twitter.php
+++ b/lib/twitter.php
@@ -360,13 +360,10 @@ function is_twitter_bound($notice, $flink) {
 
 function broadcast_twitter($notice)
 {
-    $success = true;
 
     $flink = Foreign_link::getByUserID($notice->profile_id,
         TWITTER_SERVICE);
 
-    // XXX: Not sure WHERE to check whether a notice should go to
-    // Twitter. Should we even put in the queue if it shouldn't? --Zach
     if (is_twitter_bound($notice, $flink)) {
 
         $fuser = $flink->getForeignUser();
@@ -401,33 +398,99 @@ function broadcast_twitter($notice)
         curl_setopt_array($ch, $options);
         $data = curl_exec($ch);
         $errmsg = curl_error($ch);
+        $errno = curl_errno($ch);
 
-        if ($errmsg) {
-            common_debug("cURL error: $errmsg - " .
+        if (!empty($errmsg)) {
+            common_debug("cURL error ($errno): $errmsg - " .
                 "trying to send notice for $twitter_user.",
                          __FILE__);
-            $success = false;
+
+            $user = $flink->getUser();
+
+            if ($errmsg == 'The requested URL returned error: 401') {
+                common_debug(sprintf('User %s (user id: %s) ' .
+                    'has bad Twitter credentials!',
+                    $user->nickname, $user->id));
+
+                    // Bad credentials we need to delete the foreign_link
+                    // to Twitter and inform the user.
+
+                    remove_twitter_link($flink);
+
+                    return true;
+
+            } else {
+
+                // Some other error happened, so we should try to
+                // send again later
+
+                return false;
+            }
+
         }
 
         curl_close($ch);
 
-        if (!$data) {
+        if (empty($data)) {
             common_debug("No data returned by Twitter's " .
                 "API trying to send update for $twitter_user",
                          __FILE__);
-            $success = false;
-        }
 
-        // Twitter should return a status
-        $status = json_decode($data);
+            // XXX: Not sure this represents a failure to send, but it
+            // probably does
 
-        if (!$status->id) {
-            common_debug("Unexpected data returned by Twitter " .
-                " API trying to send update for $twitter_user",
-                         __FILE__);
-            $success = false;
+            return false;
+
+        } else {
+
+            // Twitter should return a status
+            $status = json_decode($data);
+
+            if (empty($status)) {
+                common_debug("Unexpected data returned by Twitter " .
+                    " API trying to send update for $twitter_user",
+                        __FILE__);
+
+                // XXX: Again, this could represent a failure posting
+                // or the Twitter API might just be behaving flakey.
+                // We're treating it as a failure to post.
+
+                return false;
+            }
         }
     }
 
-    return $success;
+    return true;
 }
+
+function remove_twitter_link($flink)
+{
+    $user = $flink->getUser();
+
+    common_log(LOG_INFO, 'Removing Twitter bridge Foreign link for ' .
+        "user $user->nickname (user id: $user->id).");
+
+    $result = $flink->delete();
+
+    if (empty($result)) {
+        common_log(LOG_ERR, 'Could not remove Twitter bridge ' .
+            "Foreign_link for $user->nickname (user id: $user->id)!");
+        common_log_db_error($flink, 'DELETE', __FILE__);
+    }
+
+    // Notify the user that her Twitter bridge is down
+
+    $result = mail_twitter_bridge_removed($user);
+
+    if (!$result) {
+
+        $msg = 'Unable to send email to notify ' .
+            "$user->nickname (user id: $user->id) " .
+            'that their Twitter bridge link was ' .
+            'removed!';
+
+        common_log(LOG_WARNING, $msg);
+    }
+
+}
+