perf: lessen memory consumptions in a emulated mget method (#360)

Author: supercaracal

lib/redis_client/cluster/key_slot_converter.rb

@@ -70,6 +70,17 @@ def extract_hash_tag(key)
 
         key[s + 1..e - 1]
       end
+
+      def hash_tag_included?(key)
+        key = key.to_s
+        s = key.index(LEFT_BRACKET)
+        return false if s.nil?
+
+        e = key.index(RIGHT_BRACKET, s + 1)
+        return false if e.nil?
+
+        s + 1 < e
+      end
     end
   end
 end

lib/redis_client/cluster/router.rb

@@ -336,7 +336,7 @@ def send_watch_command(command)
 
       def send_multiple_keys_command(cmd, method, command, args, &block) # rubocop:disable Metrics/AbcSize, Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
         key_step = @command.determine_key_step(cmd)
-        if command.size <= key_step + 1 || !::RedisClient::Cluster::KeySlotConverter.extract_hash_tag(command[1]).empty? # rubocop:disable Style/IfUnlessModifier
+        if command.size <= key_step + 1 || ::RedisClient::Cluster::KeySlotConverter.hash_tag_included?(command[1]) # rubocop:disable Style/IfUnlessModifier
           return try_send(assign_node(command), method, command, args, &block)
         end
 

test/redis_client/cluster/test_key_slot_converter.rb

@@ -48,6 +48,27 @@ def test_extract_hash_tag
           assert_equal(c[:want], got, msg)
         end
       end
+
+      def test_hash_tag_included?
+        [
+          { key: 'foo', want: false },
+          { key: 'foo{bar}baz', want: true },
+          { key: 'foo{bar}baz{qux}quuc', want: true },
+          { key: 'foo}bar{baz', want: false },
+          { key: 'foo{bar', want: false },
+          { key: 'foo}bar', want: false },
+          { key: 'foo{}bar', want: false },
+          { key: '{}foo', want: false },
+          { key: 'foo{}', want: false },
+          { key: '{}', want: false },
+          { key: '', want: false },
+          { key: nil, want: false }
+        ].each_with_index do |c, idx|
+          msg = "Case: #{idx}"
+          got = ::RedisClient::Cluster::KeySlotConverter.hash_tag_included?(c[:key])
+          assert_equal(c[:want], got, msg)
+        end
+      end
     end
   end
 end