cli_generator.rb in departure-2.0.0

- old
+ new

@@ -1,51 +1,38 @@
+require 'departure/dsn'
+require 'departure/option'
 require 'departure/alter_argument'
+require 'departure/connection_details'
+require 'departure/user_options'
 
 module Departure
 
-  # Represents the 'DSN' argument of Percona's pt-online-schema-change
-  # See https://www.percona.com/doc/percona-toolkit/2.0/pt-online-schema-change.html#dsn-options
-  class DSN
-
-    # Constructor
-    #
-    # @param database [String, Symbol]
-    # @param table_name [String, Symbol]
-    def initialize(database, table_name)
-      @database = database
-      @table_name = table_name
-    end
-
-    # Returns the pt-online-schema-change DSN string. See
-    # https://www.percona.com/doc/percona-toolkit/2.0/pt-online-schema-change.html#dsn-options
-    def to_s
-      "D=#{database},t=#{table_name}"
-    end
-
-    private
-
-    attr_reader :table_name, :database
-  end
-
   # Generates the equivalent Percona's pt-online-schema-change command to the
   # given SQL statement
-  class CliGenerator # Command
-    BASE_COMMAND = 'pt-online-schema-change'
-    BASE_OPTIONS = %w(
-      --execute
-      --statistics
-      --recursion-method=none
-      --alter-foreign-keys-method=auto
-    )
+  #
+  # --no-check-alter is used to allow running CHANGE COLUMN statements. For
+  #   more details, check: www.percona.com/doc/percona-toolkit/2.2/pt-online-schema-change.html#cmdoption-pt-online-schema-change--[no]check-alter
+  #
+  class CliGenerator
+    COMMAND_NAME = 'pt-online-schema-change'.freeze
+    DEFAULT_OPTIONS = Set.new(
+      [
+        Option.new('execute'),
+        Option.new('statistics'),
+        Option.new('alter-foreign-keys-method', 'auto'),
+        Option.new('no-check-alter')
+      ]
+    ).freeze
 
-    # Constructor
+    # TODO: Better doc.
     #
+    # Constructor. Specify any arguments to pass to pt-online-schema-change
+    # passing the PERCONA_ARGS env var when executing the migration
+    #
     # @param connection_data [Hash]
-    def initialize(connection_data)
-      @connection_data = connection_data
-      init_base_command
-      add_connection_details
+    def initialize(connection_details)
+      @connection_details = connection_details
     end
 
     # Generates the percona command. Fills all the connection credentials from
     # the current AR connection, but that can be amended via ENV-vars:
     # PERCONA_DB_HOST, PERCONA_DB_USER, PERCONA_DB_PASSWORD, PERCONA_DB_NAME
@@ -55,13 +42,13 @@
     # @param table_name [String]
     # @param statement [String] MySQL statement
     # @return [String]
     def generate(table_name, statement)
       alter_argument = AlterArgument.new(statement)
-      dsn = DSN.new(database, table_name)
+      dsn = DSN.new(connection_details.database, table_name)
 
-      "#{self} #{dsn} #{alter_argument}"
+      "#{command} #{all_options} #{dsn} #{alter_argument}"
     end
 
     # Generates the percona command for a raw MySQL statement. Fills all the
     # connection credentials from the current AR connection, but that can
     # amended via ENV-vars: PERCONA_DB_HOST, PERCONA_DB_USER,
@@ -70,65 +57,29 @@
     #
     # @param statement [String] MySQL statement
     # @return [String]
     def parse_statement(statement)
       alter_argument = AlterArgument.new(statement)
-      dsn = DSN.new(database, alter_argument.table_name)
+      dsn = DSN.new(connection_details.database, alter_argument.table_name)
 
-      "#{self} #{dsn} #{alter_argument}"
+      "#{command} #{all_options} #{dsn} #{alter_argument}"
     end
 
     private
 
-    attr_reader :connection_data
+    attr_reader :connection_details
 
-    # Sets up the command with its options
-    def init_base_command
-      @command = [BASE_COMMAND, BASE_OPTIONS.join(' ')]
+    def command
+      "#{COMMAND_NAME} #{connection_details}"
     end
 
-    # Adds the host, user and password, if present, to the command
-    def add_connection_details
-      @command.push("-h #{host}")
-      @command.push("-u #{user}")
-      @command.push("-p #{password}") if password.present?
-    end
-
-    # Returns the command as a string that can be executed in a shell
+    # Returns all the arguments to execute pt-online-schema-change with
     #
     # @return [String]
-    def to_s
-      @command.join(' ')
-    end
-
-    # Returns the database host name, defaulting to localhost. If PERCONA_DB_HOST
-    # is passed its value will be used instead
-    #
-    # @return [String]
-    def host
-      ENV['PERCONA_DB_HOST'] || connection_data[:host] || 'localhost'
-    end
-
-    # Returns the database user. If PERCONA_DB_USER is passed its value will be
-    # used instead
-    #
-    # @return [String]
-    def user
-      ENV['PERCONA_DB_USER'] || connection_data[:username]
-    end
-
-    # Returns the database user's password. If PERCONA_DB_PASSWORD is passed its
-    # value will be used instead
-    #
-    # @return [String]
-    def password
-      ENV['PERCONA_DB_PASSWORD'] || connection_data[:password]
-    end
-
-    # TODO: Doesn't the abstract adapter already handle this somehow?
-    # Returns the database name. If PERCONA_DB_NAME is passed its value will be
-    # used instead
-    def database
-      ENV['PERCONA_DB_NAME'] || connection_data[:database]
+    def all_options
+      env_variable_options = UserOptions.new
+      global_configuration_options = UserOptions.new(Departure.configuration.global_percona_args)
+      options = env_variable_options.merge(global_configuration_options).merge(DEFAULT_OPTIONS)
+      options.to_a.join(' ')
     end
   end
 end