[Minor] Fix configwizard behaviour when DB is empty

lualib/lua_stat.lua

@@ -101,30 +101,30 @@ return nconverted
 local keys = redis.call('SMEMBERS', KEYS[1]..'_keys')
 
 for _,k in ipairs(keys) do
-  local learns = redis.call('HGET', k, 'learns')
+  local learns = redis.call('HGET', k, 'learns') or 0
   local neutral_prefix = string.gsub(k, KEYS[1], 'RS')
 
   redis.call('HSET', neutral_prefix, KEYS[2], learns)
   redis.call('SADD', KEYS[1]..'_keys', neutral_prefix)
   redis.call('SREM', KEYS[1]..'_keys', k)
-  redis.call('DEL', k)
-  redis.call('SET', KEYS[1]..'_version', '2')
+  redis.call('DEL', KEYS[1])
+  redis.call('SET', k ..'_version', '2')
 end
 ]]
 
   conn:add_cmd('EVAL', {lua_script, '2', symbol_spam, 'learns_spam'})
-  ret = conn:exec()
+  ret,res = conn:exec()
 
   if not ret then
-    logger.errx('error converting metadata for symbol %s', symbol_spam)
+    logger.errx('error converting metadata for symbol %s: %s', symbol_spam, res)
     return false
   end
 
   conn:add_cmd('EVAL', {lua_script, '2', symbol_ham, 'learns_ham'})
-  ret = conn:exec()
+  ret, res = conn:exec()
 
   if not ret then
-    logger.errx('error converting metadata for symbol %s', symbol_ham)
+    logger.errx('error converting metadata for symbol %s', symbol_ham, res)
     return false
   end
 

lualib/rspamadm/configwizard.lua

@@ -395,6 +395,13 @@ local function check_redis_classifier(cls, changes)
   end
 
   local function get_version(conn)
+    conn:add_cmd("SMEMBERS", {"RS_keys"})
+
+    local ret,members = conn:exec()
+
+    -- Empty db
+    if not ret or #members == 0 then return false,0 end
+
     -- We still need to check versions
     local lua_script = [[
 local ver = 0
@@ -469,8 +476,8 @@ return ttl
     local r,ver = get_version(conn)
     if not r then return false end
     if ver ~= 2 then
-      printf("You have configured new schema for %s/%s but your DB has old data",
-        symbol_spam, symbol_ham)
+      printf("You have configured new schema for %s/%s but your DB has old version: %s",
+        symbol_spam, symbol_ham, ver)
       try_convert(false)
     else
       printf("You have configured new schema for %s/%s and your DB already has new layout (v. %s). DB conversion is not needed.",