require 'stringio' require 'bigdecimal' module ActiveRecord # This class is used to dump the database schema for some connection to some # output format (i.e., ActiveRecord::Schema). class SchemaDumper #:nodoc: private_class_method :new # A list of tables which should not be dumped to the schema. # Acceptable values are strings as well as regexp. # This setting is only used if ActiveRecord::Base.schema_format == :ruby cattr_accessor :ignore_tables @@ignore_tables = [] def self.dump(connection=ActiveRecord::Base.connection, stream=STDOUT) new(connection).dump(stream) stream end def dump(stream) header(stream) tables(stream) trailer(stream) stream end private def initialize(connection) @connection = connection @types = @connection.native_database_types @info = @connection.select_one("SELECT * FROM schema_info") rescue nil end def header(stream) define_params = @info ? ":version => #{@info['version']}" : "" stream.puts <
"#{pk}") end else tbl.print ", :id => false" end tbl.print ", :force => true" tbl.puts " do |t|" column_specs = columns.map do |column| raise StandardError, "Unknown type '#{column.sql_type}' for column '#{column.name}'" if @types[column.type].nil? next if column.name == pk spec = {} spec[:name] = column.name.inspect spec[:type] = column.type.inspect spec[:limit] = column.limit.inspect if column.limit != @types[column.type][:limit] && column.type != :decimal spec[:precision] = column.precision.inspect if !column.precision.nil? spec[:scale] = column.scale.inspect if !column.scale.nil? spec[:null] = 'false' if !column.null spec[:default] = default_string(column.default) if !column.default.nil? (spec.keys - [:name, :type]).each{ |k| spec[k].insert(0, "#{k.inspect} => ")} spec end.compact keys = [:name, :type, :limit, :precision, :scale, :default, :null] & column_specs.map{ |spec| spec.keys }.inject([]){ |a,b| a | b } lengths = keys.map{ |key| column_specs.map{ |spec| spec[key] ? spec[key].length + 2 : 0 }.max } format_string = lengths.map{ |len| "%-#{len}s" }.join("") column_specs.each do |colspec| values = keys.zip(lengths).map{ |key, len| colspec.key?(key) ? colspec[key] + ", " : " " * len } tbl.print " t.column " tbl.print((format_string % values).gsub(/,\s*$/, '')) tbl.puts end tbl.puts " end" tbl.puts indexes(table, tbl) tbl.rewind stream.print tbl.read rescue => e stream.puts "# Could not dump table #{table.inspect} because of following #{e.class}" stream.puts "# #{e.message}" stream.puts end stream end def default_string(value) case value when BigDecimal value.to_s when Date, DateTime, Time "'" + value.to_s(:db) + "'" else value.inspect end end def indexes(table, stream) indexes = @connection.indexes(table) indexes.each do |index| stream.print " add_index #{index.table.inspect}, #{index.columns.inspect}, :name => #{index.name.inspect}" stream.print ", :unique => true" if index.unique stream.puts end stream.puts unless indexes.empty? end end end