Revert "db/manager: Drop async method"

This reverts commit e7e0c52db9093a9ecd9dcaa0766e66515a546a75.

1 files changed, 21 insertions, 6 deletions

diff --git a/alot/buffers/search.py b/alot/buffers/search.py
index d64e857f..203ef483 100644
--- a/alot/buffers/search.py
+++ b/alot/buffers/search.py
@@ -6,7 +6,7 @@ from notmuch import NotmuchError
 
 from .buffer import Buffer
 from ..settings.const import settings
-from ..walker import IterableWalker
+from ..walker import PipeWalker
 from ..widgets.search import ThreadlineWidget
 
 
@@ -26,6 +26,7 @@ class SearchBuffer(Buffer):
         self.sort_order = sort_order or default_order
         self.result_count = 0
         self.isinitialized = False
+        self.proc = None  # process that fills our pipe
         self.rebuild()
         Buffer.__init__(self, ui, self.body)
 
@@ -41,9 +42,22 @@ class SearchBuffer(Buffer):
         info['result_count_positive'] = 's' if self.result_count > 1 else ''
         return info
 
+    def cleanup(self):
+        self.kill_filler_process()
+
+    def kill_filler_process(self):
+        """
+        terminates the process that fills this buffers
+        :class:`~alot.walker.PipeWalker`.
+        """
+        if self.proc:
+            if self.proc.is_alive():
+                self.proc.terminate()
+
     def rebuild(self, reverse=False):
         self.isinitialized = True
         self.reversed = reverse
+        self.kill_filler_process()
 
         if reverse:
             order = self._REVERSE[self.sort_order]
@@ -56,8 +70,9 @@ class SearchBuffer(Buffer):
 
         try:
             self.result_count = self.dbman.count_messages(self.querystring)
-            threads = self.dbman.get_threads(
-                self.querystring, order, exclude_tags)
+            self.pipe, self.proc = self.dbman.get_threads(self.querystring,
+                                                          order,
+                                                          exclude_tags)
         except NotmuchError:
             self.ui.notify('malformed query string: %s' % self.querystring,
                            'error')
@@ -65,9 +80,9 @@ class SearchBuffer(Buffer):
             self.body = self.listbox
             return
 
-        self.threadlist = IterableWalker(threads, ThreadlineWidget,
-                                         dbman=self.dbman,
-                                         reverse=reverse)
+        self.threadlist = PipeWalker(self.pipe, ThreadlineWidget,
+                                     dbman=self.dbman,
+                                     reverse=reverse)
 
         self.listbox = urwid.ListBox(self.threadlist)
         self.body = self.listbox