Refactor keys and queries in datastore service and implementation.

filter/dscache/dscache_test.go

Index: filter/dscache/dscache_test.go
diff --git a/filter/dscache/dscache_test.go b/filter/dscache/dscache_test.go
index 6b0240d04f4f2f90c5785e9b586c83d9d85f9fba..5cdad302e3d131f00ff9bfdb408550abc727bac8 100644
--- a/filter/dscache/dscache_test.go
+++ b/filter/dscache/dscache_test.go
@@ -66,15 +66,16 @@ func TestDSCache(t *testing.T) {
 		dsUnder := datastore.Get(c)
 		mc := memcache.Get(c)
 
-		itmFor := func(i int, k datastore.Key) memcache.Item {
+		itmFor := func(i int, k *datastore.Key) memcache.Item {
 			return mc.NewItem(MakeMemcacheKey(i, k))
 		}
 
-		shardsForKey := func(k datastore.Key) int {
-			if k.Kind() == "shardObj" {
-				return int(k.IntID())
+		shardsForKey := func(k *datastore.Key) int {
+			last := k.Last()

[iannucci, 2015/09/18 04:31:52]

Key changed a bit. Now instead of k.Kind(), you get the last token with Last(),
and then that has Kind, StringID and IntID. You can also get the full list of
all the tokens in the key. Or you can recurse down it with Parent, but I wanted
to make that usecase a bit more awkward, because it involves a lot of extra
(avoidable) allocations

+			if last.Kind == "shardObj" {
+				return int(last.IntID)
 			}
-			if k.Kind() == "noCacheObj" {
+			if last.Kind == "noCacheObj" {
 				return 0
 			}
 			return DefaultShards