--- a/app/models/tweet.rb	Wed Dec 13 02:28:34 2017 +0900
+++ b/app/models/tweet.rb	Wed Dec 13 02:51:27 2017 +0900
@@ -1,20 +1,24 @@
 class Tweet
+  def initialize(twitter_id)
+    @clients = {}
+    @twitter_id = twitter_id
+  end
+
   def cache_expires_time
     (15 + rand(15)).minutes
   end
 
   def timeline
-    start_client_config_id = @client_config_id
+    initial_config_id = client_config_id
 
     @timeline ||=
       Rails.cache.fetch({ :timeline => @twitter_id }, :expires_in => cache_expires_time) do
         begin
-          @client.user_timeline(@twitter_id, :count => 100, :exclude_replies => false, :include_rts => true, :tweet_mode => :extended)
+          client.user_timeline(@twitter_id, :count => 100, :exclude_replies => false, :include_rts => true, :tweet_mode => :extended)
         rescue Twitter::Error::TooManyRequests
-          next_client_config_id = @client_config_id + 1
-          init_client next_client_config_id
+          @client_config_id += 1
 
-          if @client_config_id == start_client_config_id
+          if initial_config_id == client_config_id
             raise
           else
             retry
@@ -34,21 +38,18 @@
       end
   end
 
-  def initialize(twitter_id)
-    @client = init_client
-    @twitter_id = twitter_id
+  def client
+    @clients[client_config_id] ||=
+      Twitter::REST::Client.new do |config|
+        $cfg[:twitter][client_config_id].each do |cfg_key, cfg_value|
+          config.public_send("#{cfg_key}=", cfg_value)
+        end
+      end
   end
 
-  def init_client(config_id = 0)
-    @client_config_id = config_id
-    config_hash_key = "twitter#{config_id}".to_sym
-
-    return init_client(0) if $cfg[config_hash_key].nil? && config_id != 0
+  def client_config_id
+    @client_config_id ||= 0
 
-    @client = Twitter::REST::Client.new do |config|
-      $cfg[config_hash_key].each do |cfg_key, cfg_value|
-        config.public_send("#{cfg_key}=", cfg_value)
-      end
-    end
+    @client_config_id % $cfg[:twitter].size
   end
 end