[#1032] Keep track of torrent errors over restarts

* Add error_statusmsg to TorrentState
 * Adds a new set_error_statusmsg() method to force torrent error state.
 * Any torrent in error state will remain in that state on restart with
   additional message in status.
 * Any new libtorrent errors will override manually set ones.

deluge/core/torrent.py

@@ -216,6 +216,11 @@ class Torrent(object):
             self.set_trackers(state.trackers)
             self.filename = state.filename
             self.is_finished = state.is_finished
+            last_sess_prepend = "[Error from Previous Session] "
+            if state.error_statusmsg and not state.error_statusmsg.startswith(last_sess_prepend):
+                self.error_statusmsg = last_sess_prepend + state.error_statusmsg
+            else:
+                self.error_statusmsg = state.error_statusmsg
         else:
             self.trackers = [tracker for tracker in self.handle.trackers()]
             self.is_finished = False
@@ -224,6 +229,7 @@ class Torrent(object):
                 self.filename = self.torrent_id
             else:
                 self.filename = filename
+            self.error_statusmsg = None
 
         self.statusmsg = "OK"
         self.state = None
@@ -592,16 +598,23 @@ class Torrent(object):
             log.debug("session.is_paused: %s", session_is_paused)
 
         # First we check for an error from libtorrent, and set the state to that if any occurred.
-        if status.error or self.statusmsg.startswith("Error:"):
+        if status.error or self.error_statusmsg:
             # This is an error'd torrent
             self.state = "Error"
             if status.error:
-                self.set_status_message(status.error)
+                self.set_error_statusmsg(status.error)
-            if status.paused:
+            self.set_status_message(self.error_statusmsg)
+            # This will be reverted upon resuming.
             self.handle.auto_managed(False)
+            if not status.paused:
+                self.handle.pause()
+            if not status.error:
+                # As this is not a libtorrent Error we should emit a state changed event
+                component.get("EventManager").emit(TorrentStateChangedEvent(self.torrent_id, "Error"))
             return
         else:
             self.set_status_message("OK")
+            self.set_error_statusmsg(None)
 
         if self.moving_storage:
             self.state = "Moving"
@@ -646,6 +659,19 @@ class Torrent(object):
         """
         self.statusmsg = message
 
+    def set_error_statusmsg(self, message):
+        """Sets the torrent error status message.
+
+        Note:
+            This will force a torrent into an error state. It is used for
+            setting those errors that are not covered by libtorrent.
+
+        Args:
+            message (str): The error status message.
+
+        """
+        self.error_statusmsg = message
+
     def get_eta(self):
         """Get the ETA for this torrent.
 
@@ -853,7 +879,9 @@ class Torrent(object):
             files = [os.path.join(path, f) for f in files]
             return sum(os.stat(f).st_size for f in files if os.path.exists(f))
 
-        if self.moving_storage:
+        if self.state == "Error":
+            progress = 100.0
+        elif self.moving_storage:
             torrent_status = self.get_status(["files", "total_done"])
             torrent_files = [f['path'] for f in torrent_status["files"]]
             dest_path_size = get_size(torrent_files, self.moving_storage_dest_path)
@@ -1026,6 +1054,7 @@ class Torrent(object):
 
         # Reset the status message just in case of resuming an Error'd torrent
         self.set_status_message("OK")
+        self.set_error_statusmsg(None)
 
         if self.status.is_finished:
             # If the torrent has already reached it's 'stop_seed_ratio' then do not do anything

deluge/core/torrentmanager.py

@@ -54,6 +54,7 @@ class TorrentState:
                  queue=None,
                  auto_managed=True,
                  is_finished=False,
+                 error_statusmsg=None,
                  stop_ratio=2.00,
                  stop_at_ratio=False,
                  remove_at_ratio=False,
@@ -654,7 +655,7 @@ class TorrentManager(component.Component):
         # Create the state for each Torrent and append to the list
         for torrent in self.torrents.values():
             paused = False
-            if torrent.state == "Paused":
+            if torrent.state in ["Paused", "Error"]:
                 paused = True
 
             torrent_state = TorrentState(
@@ -674,6 +675,7 @@ class TorrentManager(component.Component):
                 torrent.get_queue_position(),
                 torrent.options["auto_managed"],
                 torrent.is_finished,
+                torrent.error_statusmsg,
                 torrent.options["stop_ratio"],
                 torrent.options["stop_at_ratio"],
                 torrent.options["remove_at_ratio"],
@@ -1043,7 +1045,7 @@ class TorrentManager(component.Component):
             return
         # Set an Error message and pause the torrent
         alert_msg = decode_string(alert.message()).split(':', 1)[1].strip()
-        torrent.set_status_message("Error: Moving storage failed, %s" % alert_msg)
+        torrent.set_error_statusmsg("Failed to move storage: %s" % alert_msg)
         torrent.moving_storage = False
         torrent.pause()
         torrent.update_state()