nmbug-status: add support for specifying sort order for each view

Let each view have a "sort" key, typically used with values
"oldest-first" or "newest-first" (although all values in Query.SORT
are accepted), and sort the results accordingly. Oldest first remains
the default.

The dynamic approach of mapping sort values is as suggested by
W. Trevor King <wking@tremily.us>.

diff --git a/devel/nmbug/nmbug-status b/devel/nmbug/nmbug-status
index e845c2a5c8f702cc5d988fa6ea16ba3b0e53e828..a289798e3cc18559584de5cccda81d0f95c4e392 100755 (executable)
--- a/devel/nmbug/nmbug-status
+++ b/devel/nmbug/nmbug-status
@@ -156,11 +156,20 @@ class Page (object):
             stream.write(self.footer)
 
     def _write_view(self, database, view, stream):
+        # sort order, default to oldest-first
+        sort_key = view.get('sort', 'oldest-first')
+        # dynamically accept all values in Query.SORT
+        sort_attribute = sort_key.upper().replace('-', '_')
+        try:
+            sort = getattr(notmuch.Query.SORT, sort_attribute)
+        except AttributeError:
+            raise ConfigError('Invalid sort setting for {}: {!r}'.format(
+                view['title'], sort_key))
         if 'query-string' not in view:
             query = view['query']
             view['query-string'] = ' and '.join(query)
         q = notmuch.Query(database, view['query-string'])
-        q.set_sort(notmuch.Query.SORT.OLDEST_FIRST)
+        q.set_sort(sort)
         threads = self._get_threads(messages=q.search_messages())
         self._write_view_header(view=view, stream=stream)
         self._write_threads(threads=threads, stream=stream)