From f29d1fb0b20d31c39ea4d092ecd4eb1e4d2f5e1b Mon Sep 17 00:00:00 2001
From: Salvatore Sanfilippo <antirez@gmail.com>
Date: Mon, 11 Apr 2011 18:26:00 +0200
Subject: [PATCH] assert_empty in redis-trib

---
 src/redis-trib.rb | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/redis-trib.rb b/src/redis-trib.rb
index 8456ed29..98ed0a0e 100755
--- a/src/redis-trib.rb
+++ b/src/redis-trib.rb
@@ -43,6 +43,14 @@ class ClusterNode
         end
     end
 
+    def assert_empty
+        if !(@r.cluster("info").split("\r\n").index("cluster_known_nodes:1")) ||
+            (@r.info['db0'])
+            puts "Error: Node #{self} is not empty. Either the node already knows other nodes (check with nodes-info) or contains some key in database 0."
+            exit 1
+        end
+    end
+
     def r
         @r
     end
@@ -63,7 +71,7 @@ class RedisTrib
             node = ClusterNode.new(n)
             node.connect
             node.assert_cluster
-            # node.assert_empty
+            node.assert_empty
         }
     end
 end