perf: command builder shouldn't be called multiple times

.gitignore

@@ -1,3 +1,4 @@
 .bundle
 *.gem
+*.json
 Gemfile.lock

Gemfile

@@ -15,3 +15,4 @@ gem 'rubocop-minitest', require: false
 gem 'rubocop-performance', require: false
 gem 'rubocop-rake', require: false
 gem 'stackprof', platform: :mri
+gem 'vernier', platform: :mri if RUBY_ENGINE == 'ruby' && Integer(RUBY_VERSION.split('.').first) > 2

lib/redis_client/cluster.rb

@@ -62,30 +62,37 @@ def blocking_call_v(timeout, command, &block)
     end
 
     def scan(*args, **kwargs, &block)
-      raise ArgumentError, 'block required' unless block
+      return to_enum(__callee__, *args, **kwargs) unless block_given?
 
+      command = @command_builder.generate(['SCAN', ZERO_CURSOR_FOR_SCAN] + args, kwargs)
       seed = Random.new_seed
-      cursor = ZERO_CURSOR_FOR_SCAN
       loop do
-        cursor, keys = router.scan('SCAN', cursor, *args, seed: seed, **kwargs)
+        cursor, keys = router.scan(command, seed: seed)
+        command[1] = cursor
         keys.each(&block)
         break if cursor == ZERO_CURSOR_FOR_SCAN
       end
     end
 
     def sscan(key, *args, **kwargs, &block)
-      node = router.assign_node(['SSCAN', key])
-      router.try_delegate(node, :sscan, key, *args, **kwargs, &block)
+      return to_enum(__callee__, key, *args, **kwargs) unless block_given?
+
+      command = @command_builder.generate(['SSCAN', key, ZERO_CURSOR_FOR_SCAN] + args, kwargs)
+      router.scan_single_key(command, arity: 1, &block)
     end
 
     def hscan(key, *args, **kwargs, &block)
-      node = router.assign_node(['HSCAN', key])
-      router.try_delegate(node, :hscan, key, *args, **kwargs, &block)
+      return to_enum(__callee__, key, *args, **kwargs) unless block_given?
+
+      command = @command_builder.generate(['HSCAN', key, ZERO_CURSOR_FOR_SCAN] + args, kwargs)
+      router.scan_single_key(command, arity: 2, &block)
     end
 
     def zscan(key, *args, **kwargs, &block)
-      node = router.assign_node(['ZSCAN', key])
-      router.try_delegate(node, :zscan, key, *args, **kwargs, &block)
+      return to_enum(__callee__, key, *args, **kwargs) unless block_given?
+
+      command = @command_builder.generate(['ZSCAN', key, ZERO_CURSOR_FOR_SCAN] + args, kwargs)
+      router.scan_single_key(command, arity: 2, &block)
     end
 
     def pipelined(exception: true)

lib/redis_client/cluster/noop_command_builder.rb

@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class RedisClient
+  class Cluster
+    module NoopCommandBuilder
+      module_function
+
+      def generate(args, _kwargs = nil)
+        args
+      end
+    end
+  end
+end

lib/redis_client/cluster/pipeline.rb

@@ -2,6 +2,7 @@
 
 require 'redis_client'
 require 'redis_client/cluster/errors'
+require 'redis_client/cluster/noop_command_builder'
 require 'redis_client/connection_mixin'
 require 'redis_client/middlewares'
 require 'redis_client/pooled'
@@ -229,7 +230,7 @@ def execute # rubocop:disable Metrics/AbcSize, Metrics/CyclomaticComplexity, Met
 
       def append_pipeline(node_key)
         @pipelines ||= {}
-        @pipelines[node_key] ||= ::RedisClient::Cluster::Pipeline::Extended.new(@command_builder)
+        @pipelines[node_key] ||= ::RedisClient::Cluster::Pipeline::Extended.new(::RedisClient::Cluster::NoopCommandBuilder)
         @pipelines[node_key].add_outer_index(@size)
         @size += 1
         @pipelines[node_key]

lib/redis_client/cluster/router.rb

@@ -104,12 +104,6 @@ def try_send(node, method, command, args, retry_count: 3, &block)
         end
       end
 
-      def try_delegate(node, method, *args, retry_count: 3, **kwargs, &block)
-        handle_redirection(node, nil, retry_count: retry_count) do |on_node|
-          on_node.public_send(method, *args, **kwargs, &block)
-        end
-      end
-
       def handle_redirection(node, command, retry_count:) # rubocop:disable Metrics/AbcSize, Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
         yield node
       rescue ::RedisClient::CircuitBreaker::OpenCircuitError
@@ -153,9 +147,7 @@ def handle_redirection(node, command, retry_count:) # rubocop:disable Metrics/Ab
         raise
       end
 
-      def scan(*command, seed: nil, **kwargs) # rubocop:disable Metrics/AbcSize
-        command = @command_builder.generate(command, kwargs)
-
+      def scan(command, seed: nil) # rubocop:disable Metrics/AbcSize
         command[1] = ZERO_CURSOR_FOR_SCAN if command.size == 1
         input_cursor = Integer(command[1])
 
@@ -180,6 +172,16 @@ def scan(*command, seed: nil, **kwargs) # rubocop:disable Metrics/AbcSize
         raise
       end
 
+      def scan_single_key(command, arity:, &block)
+        node = assign_node(command)
+        loop do
+          cursor, values = handle_redirection(node, nil, retry_count: 3) { |n| n.call_v(command) }
+          command[2] = cursor
+          arity < 2 ? values.each(&block) : values.each_slice(arity, &block)
+          break if cursor == ZERO_CURSOR_FOR_SCAN
+        end
+      end
+
       def assign_node(command)
         handle_node_reload_error do
           node_key = find_node_key(command)

lib/redis_client/cluster/transaction.rb

@@ -2,6 +2,7 @@
 
 require 'redis_client'
 require 'redis_client/cluster/errors'
+require 'redis_client/cluster/noop_command_builder'
 require 'redis_client/cluster/pipeline'
 
 class RedisClient
@@ -18,7 +19,7 @@ def initialize(router, command_builder, node: nil, slot: nil, asking: false)
         @router = router
         @command_builder = command_builder
         @retryable = true
-        @pipeline = ::RedisClient::Pipeline.new(@command_builder)
+        @pipeline = ::RedisClient::Pipeline.new(::RedisClient::Cluster::NoopCommandBuilder)
         @pending_commands = []
         @node = node
         prepare_tx unless @node.nil?

lib/redis_client/cluster_config.rb

@@ -5,6 +5,7 @@
 require 'redis_client/cluster'
 require 'redis_client/cluster/errors'
 require 'redis_client/cluster/node_key'
+require 'redis_client/cluster/noop_command_builder'
 require 'redis_client/command_builder'
 
 class RedisClient
@@ -64,7 +65,7 @@ def initialize( # rubocop:disable Metrics/ParameterLists
     end
 
     def inspect
-      "#<#{self.class.name} #{startup_nodes.values}>"
+      "#<#{self.class.name} #{startup_nodes.values.map { |v| v.reject { |k| k == :command_builder } }}>"
     end
 
     def read_timeout
@@ -187,6 +188,7 @@ def build_startup_nodes(configs)
     def augment_client_config(config)
       config = @client_config.merge(config)
       config = config.merge(host: @fixed_hostname) unless @fixed_hostname.empty?
+      config[:command_builder] = ::RedisClient::Cluster::NoopCommandBuilder # prevent twice call
       config
     end
   end

test/prof_stack2.rb

@@ -0,0 +1,78 @@
+# frozen_string_literal: true
+
+require 'vernier'
+require 'redis_cluster_client'
+require 'testing_constants'
+
+module ProfStack2
+  SIZE = 40
+  ATTEMPTS = 1000
+
+  module_function
+
+  def run
+    client = make_client
+    prepare(client)
+
+    case mode = ENV.fetch('PROFILE_MODE', :single).to_sym
+    when :single
+      execute(client, mode) do |client|
+        ATTEMPTS.times { |i| client.call('GET', "key#{i}") }
+      end
+    when :transaction
+      execute(client, mode) do |client|
+        ATTEMPTS.times do |i|
+          client.multi do |tx|
+            SIZE.times do |j|
+              n = SIZE * i + j
+              tx.call('SET', "{group:#{i}}:key:#{n}", n)
+            end
+          end
+        end
+      end
+    when :pipeline
+      execute(client, mode) do |client|
+        ATTEMPTS.times do |i|
+          client.pipelined do |pi|
+            SIZE.times do |j|
+              n = SIZE * i + j
+              pi.call('GET', "key#{n}")
+            end
+          end
+        end
+      end
+    end
+  end
+
+  def execute(client, mode)
+    Vernier.profile(out: "vernier_#{mode}.json") do
+      yield(client)
+    end
+  end
+
+  def make_client
+    ::RedisClient.cluster(
+      nodes: TEST_NODE_URIS,
+      replica: true,
+      replica_affinity: :random,
+      fixed_hostname: TEST_FIXED_HOSTNAME,
+      # concurrency: { model: :on_demand, size: 6 },
+      # concurrency: { model: :pooled, size: 6 },
+      concurrency: { model: :none },
+      **TEST_GENERIC_OPTIONS
+    ).new_client
+  end
+
+  def prepare(client)
+    ATTEMPTS.times do |i|
+      client.pipelined do |pi|
+        SIZE.times do |j|
+          n = SIZE * i + j
+          pi.call('SET', "key#{n}", "val#{n}")
+        end
+      end
+    end
+  end
+end
+
+ProfStack2.run

test/redis_client/test_cluster.rb

@@ -92,8 +92,6 @@ def test_blocking_call
       end
 
       def test_scan
-        assert_raises(ArgumentError) { @client.scan }
-
         10.times { |i| @client.call('SET', "key#{i}", i) }
         wait_for_replication
         want = (0..9).map { |i| "key#{i}" }
@@ -117,9 +115,9 @@ def test_hscan
         10.times do |i|
           10.times { |j| @client.call('HSET', "key#{i}", "field#{j}", j) }
           wait_for_replication
-          want = (0..9).map { |j| "field#{j}" }
+          want = (0..9).map { |j| ["field#{j}", j.to_s] }
           got = []
-          @client.hscan("key#{i}", 'COUNT', '5') { |field| got << field }
+          @client.hscan("key#{i}", 'COUNT', '5') { |pair| got << pair }
           assert_equal(want, got.sort)
         end
       end
@@ -128,9 +126,9 @@ def test_zscan
         10.times do |i|
           10.times { |j| @client.call('ZADD', "key#{i}", j, "member#{j}") }
           wait_for_replication
-          want = (0..9).map { |j| "member#{j}" }
+          want = (0..9).map { |j| ["member#{j}", j.to_s] }
           got = []
-          @client.zscan("key#{i}", 'COUNT', '5') { |member| got << member }
+          @client.zscan("key#{i}", 'COUNT', '5') { |pair| got << pair }
           assert_equal(want, got.sort)
         end
       end

test/redis_client/test_cluster_config.rb

@@ -38,38 +38,38 @@ def test_startup_nodes
         {
           config: ::RedisClient::ClusterConfig.new,
           want: {
-            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379 }
+            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379, command_builder: ::RedisClient::Cluster::NoopCommandBuilder }
           }
         },
         {
           config: ::RedisClient::ClusterConfig.new(replica: true),
           want: {
-            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379 }
+            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379, command_builder: ::RedisClient::Cluster::NoopCommandBuilder }
           }
         },
         {
           config: ::RedisClient::ClusterConfig.new(fixed_hostname: 'endpoint.example.com'),
           want: {
-            '127.0.0.1:6379' => { host: 'endpoint.example.com', port: 6379 }
+            '127.0.0.1:6379' => { host: 'endpoint.example.com', port: 6379, command_builder: ::RedisClient::Cluster::NoopCommandBuilder }
           }
         },
         {
           config: ::RedisClient::ClusterConfig.new(timeout: 1),
           want: {
-            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379, timeout: 1 }
+            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379, timeout: 1, command_builder: ::RedisClient::Cluster::NoopCommandBuilder }
           }
         },
         {
           config: ::RedisClient::ClusterConfig.new(nodes: ['redis://1.2.3.4:1234', 'rediss://5.6.7.8:5678']),
           want: {
-            '1.2.3.4:1234' => { host: '1.2.3.4', port: 1234 },
-            '5.6.7.8:5678' => { host: '5.6.7.8', port: 5678, ssl: true }
+            '1.2.3.4:1234' => { host: '1.2.3.4', port: 1234, command_builder: ::RedisClient::Cluster::NoopCommandBuilder },
+            '5.6.7.8:5678' => { host: '5.6.7.8', port: 5678, ssl: true, command_builder: ::RedisClient::Cluster::NoopCommandBuilder }
           }
         },
         {
           config: ::RedisClient::ClusterConfig.new(custom: { foo: 'bar' }),
           want: {
-            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379, custom: { foo: 'bar' } }
+            '127.0.0.1:6379' => { host: '127.0.0.1', port: 6379, custom: { foo: 'bar' }, command_builder: ::RedisClient::Cluster::NoopCommandBuilder }
           }
         }
       ].each_with_index do |c, idx|
@@ -182,13 +182,15 @@ def test_client_config_for_node
         nodes: ['redis://username:password@1.2.3.4:1234', 'rediss://5.6.7.8:5678'],
         custom: { foo: 'bar' }
       )
-      assert_equal({
-                     host: '9.9.9.9',
-                     port: 9999,
-                     username: 'username',
-                     password: 'password',
-                     custom: { foo: 'bar' }
-                   }, config.client_config_for_node('9.9.9.9:9999'))
+      want = {
+        host: '9.9.9.9',
+        port: 9999,
+        username: 'username',
+        password: 'password',
+        custom: { foo: 'bar' },
+        command_builder: ::RedisClient::Cluster::NoopCommandBuilder
+      }
+      assert_equal(want, config.client_config_for_node('9.9.9.9:9999'))
     end
 
     def test_client_config_id