store feed errors

storage/feed.go

@@ -132,3 +132,21 @@ func (s *Storage) GetFeed(id int64) *Feed {
 	}
 	return nil
 }
+
+func (s *Storage) ResetFeedErrors() {
+	if _, err := s.db.Exec(`delete from feed_errors`); err != nil {
+		s.log.Print(err)
+	}
+}
+
+func (s *Storage) SetFeedError(feedID int64, lastError error) {
+	_, err := s.db.Exec(`
+		insert into feed_errors (feed_id, error)
+		values (?, ?)
+		on conflict (feed_id) do update set error = excluded.error`,
+		feedID, lastError.Error(),
+	)
+	if err != nil {
+		s.log.Print(err)
+	}
+}

storage/storage.go

@@ -65,12 +65,16 @@ end;
 create table if not exists http_states (
  feed_id        references feeds(id) unique,
  last_refreshed datetime not null,
- last_error     string,
 
  -- http header fields --
  last_modified  string not null,
  etag           string not null
 );
+
+create table if not exists feed_errors (
+ feed_id        references feeds(id) unique,
+ error          string
+);
 `
 
 type Storage struct {