Redis configuration extraction #8439

config/initializers/load_resque.rb

@@ -2,17 +2,9 @@ require 'resque'
 require 'resque/failure/base'
 require 'resque/failure/multiple'
 require 'resque/failure/redis'
+require_dependency 'redis_factory'
 
 # Load automatically all resque files from lib/resque
 Dir[Rails.root.join("lib/resque/*.rb")].each {|f| require f}
 
-conf = Cartodb.config[:redis].symbolize_keys
-redis_conf = conf.select { |k, v| [:host, :port, :tcp_keepalive].include?(k) }
-redis_conf[:connect_timeout] = 2
-redis_conf[:read_timeout] = 3
-redis_conf[:write_timeout] = 5
-if redis_conf[:tcp_keepalive] and redis_conf[:tcp_keepalive].is_a? Hash
-  redis_conf[:tcp_keepalive] = redis_conf[:tcp_keepalive].symbolize_keys
-end
-
-Resque.redis = Redis.new(redis_conf)
+Resque.redis = RedisFactory.new_connection

config/initializers/redis.rb

@@ -1,3 +1,5 @@
+require_dependency 'redis_factory'
+
 if Cartodb.config[:redis].blank?
   raise <<-MESSAGE
 Please, configure Redis in your config/app_config.yml file like this:
@@ -9,45 +11,11 @@ Please, configure Redis in your config/app_config.yml file like this:
 MESSAGE
 end
 
-# Redis interfaces definition:
-conf = Cartodb.config[:redis].symbolize_keys
-
-# TODO: because of #8439 we're testing different Redis timeouts for connection, R and W.
-# After getting a final solution timeout configuration should be read from the file again
-redis_conf = conf.select { |k, v| [:host, :port, :driver, :tcp_keepalive].include?(k) }
-redis_conf[:connect_timeout] = 2
-redis_conf[:read_timeout] = 3
-redis_conf[:write_timeout] = 5
-
-if ENV['REDIS_PORT']
-  redis_conf[:port] = ENV['REDIS_PORT']
-end
-
-if redis_conf[:tcp_keepalive] and redis_conf[:tcp_keepalive].is_a? Hash
-  redis_conf[:tcp_keepalive] = redis_conf[:tcp_keepalive].symbolize_keys
-end
-if redis_conf[:driver] and redis_conf[:driver].is_a? String
-  redis_conf.merge! :driver => redis_conf[:driver].to_sym
-end
-
-default_databases = {
-  tables_metadata:     0,
-  api_credentials:     3,
-  users_metadata:      5,
-  redis_migrator_logs: 6
-}
-
-databases = if conf[:databases].blank?
-  default_databases
-else
-  conf[:databases].symbolize_keys
-end
-
-$tables_metadata     = Redis.new(redis_conf.merge(db: databases[:tables_metadata]))
-$api_credentials     = Redis.new(redis_conf.merge(db: databases[:api_credentials]))
-$users_metadata      = Redis.new(redis_conf.merge(db: databases[:users_metadata]))
-$redis_migrator_logs = Redis.new(redis_conf.merge(db: databases[:redis_migrator_logs]))
-$geocoder_metrics    = Redis.new(redis_conf.merge(db: databases[:users_metadata]))
+$tables_metadata     = RedisFactory.new_connection(db_id: :tables_metadata)
+$api_credentials     = RedisFactory.new_connection(db_id: :api_credentials)
+$users_metadata      = RedisFactory.new_connection(db_id: :users_metadata)
+$redis_migrator_logs = RedisFactory.new_connection(db_id: :redis_migrator_logs)
+$geocoder_metrics    = RedisFactory.new_connection(db_id: :users_metadata)
 
 # When in the "test" environment we don't expect a Redis
 # server to be up and running at this point. Later code

lib/redis_factory.rb

@@ -0,0 +1,53 @@
+class RedisFactory
+  # db_id: configuration databases entry key (:tables_metadata, :api_credentials...)
+  def self.new_connection(db_id: nil)
+    configuration = get_conf
+    configuration[:db] = databases[db_id] if db_id.present?
+    Redis.new(configuration)
+  end
+
+  def self.get_conf
+    # TODO: because of #8439 we're testing different Redis timeouts for connection, R and W.
+    # After getting a final solution timeout configuration should be read from the file again
+    redis_conf = conf.select { |k, _| [:host, :port, :driver, :tcp_keepalive].include?(k) }
+    redis_conf[:connect_timeout] = 2
+    redis_conf[:read_timeout] = 3
+    redis_conf[:write_timeout] = 5
+
+    if ENV['REDIS_PORT']
+      redis_conf[:port] = ENV['REDIS_PORT']
+    end
+
+    if redis_conf[:tcp_keepalive] and redis_conf[:tcp_keepalive].is_a? Hash
+      redis_conf[:tcp_keepalive] = redis_conf[:tcp_keepalive].symbolize_keys
+    end
+    if redis_conf[:driver] and redis_conf[:driver].is_a? String
+      redis_conf.merge! :driver => redis_conf[:driver].to_sym
+    end
+
+    redis_conf
+  end
+
+  def self.databases
+    if conf[:databases].blank?
+      @@default_databases
+    else
+      conf[:databases].symbolize_keys
+    end
+  end
+
+  @@default_databases = {
+    tables_metadata:     0,
+    api_credentials:     3,
+    users_metadata:      5,
+    redis_migrator_logs: 6
+  }.freeze
+
+  def self.conf
+    # Note that `symbolize_keys` creates a new instance, which is relevant to avoid side effects
+    Cartodb.config[:redis].symbolize_keys
+  end
+
+  private_class_method :get_conf
+  private_class_method :databases
+end