Add ability to sort change list

Added key bindings to sort the change list by number (current default), and by
the time the change was last updated. Also added the ability to reverse the
sort, useful for showing the most recent changes at the top of the screen.

Doesn't depend on but sorting by updated column makes more sense with this
patchset: https://review.openstack.org/#/c/122176/

Change-Id: I4d0ee462c106e26857785c9b4e26cc17e906796a

gertty/db.py

@@ -578,12 +578,15 @@ class DatabaseSession(object):
         except sqlalchemy.orm.exc.NoResultFound:
             return None
 
-    def getChanges(self, query, unreviewed=False):
+    def getChanges(self, query, unreviewed=False, sort_by='number'):
         self.database.log.debug("Search query: %s" % query)
         q = self.session().query(Change).filter(self.search.parse(query))
         if unreviewed:
             q = q.filter(change_table.c.hidden==False, change_table.c.reviewed==False)
-        q = q.order_by(change_table.c.number)
+        if sort_by == 'updated':
+            q = q.order_by(change_table.c.updated)
+        else:
+            q = q.order_by(change_table.c.number)
         self.database.log.debug("Search SQL: %s" % q)
         try:
             return q.all()

gertty/keymap.py

@@ -53,6 +53,9 @@ REFRESH = 'refresh'
 EDIT_TOPIC = 'edit topic'
 EDIT_COMMIT_MESSAGE = 'edit commit message'
 SUBMIT_CHANGE = 'submit change'
+SORT_BY_NUMBER = 'sort by number'
+SORT_BY_UPDATED = 'sort by updated'
+SORT_BY_REVERSE = 'reverse the sort'
 # Project list screen:
 TOGGLE_LIST_REVIEWED = 'toggle list reviewed'
 TOGGLE_LIST_SUBSCRIBED = 'toggle list subscribed'
@@ -97,6 +100,9 @@ DEFAULT_KEYMAP = {
     EDIT_TOPIC: 'ctrl t',
     EDIT_COMMIT_MESSAGE: 'ctrl d',
     SUBMIT_CHANGE: 'ctrl u',
+    SORT_BY_NUMBER: 'n',
+    SORT_BY_UPDATED: 'u',
+    SORT_BY_REVERSE: 'r',
 
     TOGGLE_LIST_REVIEWED: 'l',
     TOGGLE_LIST_SUBSCRIBED: 'L',

gertty/view/change_list.py

@@ -106,7 +106,13 @@ class ChangeListView(urwid.WidgetWrap):
             (key(keymap.TOGGLE_REVIEWED),
              "Toggle the reviewed flag for the currently selected change"),
             (key(keymap.REFRESH),
-             "Sync all projects")
+             "Sync all projects"),
+            (key(keymap.SORT_BY_NUMBER),
+             "Sort changes by number"),
+            (key(keymap.SORT_BY_UPDATED),
+             "Sort changes by how recently the change was updated"),
+            (key(keymap.SORT_BY_REVERSE),
+             "Reverse the sort")
             ]
 
     def __init__(self, app, query, query_desc=None, unreviewed=False):
@@ -120,6 +126,8 @@ class ChangeListView(urwid.WidgetWrap):
         self.display_owner = self.display_project = self.display_updated = True
         if '_project_key' in query:
             self.display_project = False
+        self.sort_by = 'number'
+        self.reverse = False
         self.header = ChangeListHeader(self.display_project, self.display_owner,
                                        self.display_updated)
         self.categories = []
@@ -133,7 +141,8 @@ class ChangeListView(urwid.WidgetWrap):
     def refresh(self):
         unseen_keys = set(self.change_rows.keys())
         with self.app.db.getSession() as session:
-            lst = session.getChanges(self.query, self.unreviewed)
+            lst = session.getChanges(self.query, self.unreviewed,
+                                     sort_by=self.sort_by)
             if self.unreviewed:
                 self.title = u'Unreviewed changes in %s' % self.query_desc
             else:
@@ -144,7 +153,11 @@ class ChangeListView(urwid.WidgetWrap):
                 categories |= set(change.getCategories())
             self.categories = sorted(categories)
             i = 0
-            for change in lst:
+            if self.reverse:
+                change_list = reversed(lst)
+            else:
+                change_list = lst
+            for change in change_list:
                 row = self.change_rows.get(change.key)
                 if not row:
                     row = ChangeRow(change, self.categories, self.display_project,
@@ -163,6 +176,11 @@ class ChangeListView(urwid.WidgetWrap):
             self.listbox.body.remove(row)
             del self.change_rows[key]
 
+    def clearChangeList(self):
+        for key, value in self.change_rows.iteritems():
+            self.listbox.body.remove(value)
+        self.change_rows = {}
+
     def getNextChangeKey(self, change_key):
         row = self.change_rows.get(change_key)
         try:
@@ -225,6 +243,30 @@ class ChangeListView(urwid.WidgetWrap):
                 sync.SyncSubscribedProjectsTask(sync.HIGH_PRIORITY))
             self.app.status.update()
             return None
+        if keymap.SORT_BY_NUMBER in commands:
+            if not len(self.listbox.body):
+                return None
+            self.sort_by = 'number'
+            self.clearChangeList()
+            self.refresh()
+            return None
+        if keymap.SORT_BY_UPDATED in commands:
+            if not len(self.listbox.body):
+                return None
+            self.sort_by = 'updated'
+            self.clearChangeList()
+            self.refresh()
+            return None
+        if keymap.SORT_BY_REVERSE in commands:
+            if not len(self.listbox.body):
+                return None
+            if self.reverse:
+                self.reverse = False
+            else:
+                self.reverse = True
+            self.clearChangeList()
+            self.refresh()
+            return None
         return key
 
     def onSelect(self, button, change_key):