From 16266c6e700513fd60abafc88de205951cbea90e Mon Sep 17 00:00:00 2001
From: Charles Haley <>
Date: Sun, 19 Sep 2010 20:11:39 +0100
Subject: [PATCH] Change field_keys to sortable_keys

---
 src/calibre/library/caches.py         | 2 +-
 src/calibre/library/field_metadata.py | 6 ++++--
 src/calibre/library/server/content.py | 2 +-
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/calibre/library/caches.py b/src/calibre/library/caches.py
index 073f98583c..770a362a1d 100644
--- a/src/calibre/library/caches.py
+++ b/src/calibre/library/caches.py
@@ -621,7 +621,7 @@ class ResultCache(SearchQueryParser):
 
     def multisort(self, fields=[], subsort=False):
         fields = [(self.sanitize_sort_field_name(x), bool(y)) for x, y in fields]
-        keys = self.field_metadata.field_keys()
+        keys = self.field_metadata.sortable_keys()
         fields = [x for x in fields if x[0] in keys]
         if subsort and 'sort' not in [x[0] for x in fields]:
             fields += [('sort', True)]
diff --git a/src/calibre/library/field_metadata.py b/src/calibre/library/field_metadata.py
index 971d91b248..e4a4f5270d 100644
--- a/src/calibre/library/field_metadata.py
+++ b/src/calibre/library/field_metadata.py
@@ -348,8 +348,10 @@ class FieldMetadata(dict):
     def keys(self):
         return self._tb_cats.keys()
 
-    def field_keys(self):
-        return [k for k in self._tb_cats.keys() if self._tb_cats[k]['kind']=='field']
+    def sortable_keys(self):
+        return [k for k in self._tb_cats.keys()
+                if self._tb_cats[k]['kind']=='field' and
+                   self._tb_cats[k]['datatype'] is not None]
 
     def iterkeys(self):
         for key in self._tb_cats:
diff --git a/src/calibre/library/server/content.py b/src/calibre/library/server/content.py
index 95794a8c1d..acfc1f9ab1 100644
--- a/src/calibre/library/server/content.py
+++ b/src/calibre/library/server/content.py
@@ -56,7 +56,7 @@ class ContentServer(object):
 
     def sort(self, items, field, order):
         field = self.db.data.sanitize_sort_field_name(field)
-        if field not in self.db.field_metadata.field_keys():
+        if field not in self.db.field_metadata.sortable_keys():
             raise cherrypy.HTTPError(400, '%s is not a valid sort field'%field)
         keyg = CSSortKeyGenerator([(field, order)], self.db.field_metadata)
         items.sort(key=keyg, reverse=not order)