# -*- coding: utf-8 -*- module SchemaComments class SchemaDumper < ActiveRecord::SchemaDumper private def tables(stream) result = super(stream) # ビューはtableの後に実行するようにしないと rake db:schema:load で失敗します。 mysql_views(stream) if adapter_name == "mysql" result end def mysql_view?(table) return false unless adapter_name == 'mysql' config = ActiveRecord::Base.configurations[Rails.env] match_count = @connection.select_value( "select count(*) from information_schema.TABLES where TABLE_TYPE = 'VIEW' AND TABLE_SCHEMA = '%s' AND TABLE_NAME = '%s'" % [ config["database"], table]) match_count.to_i > 0 end def table(table, stream) # MySQLは、ビューもテーブルとして扱うので、一個一個チェックします。 return if mysql_view?(table) columns = @connection.columns(table) begin tbl = StringIO.new # first dump primary key column if @connection.respond_to?(:pk_and_sequence_for) pk, _ = @connection.pk_and_sequence_for(table) elsif @connection.respond_to?(:primary_key) pk = @connection.primary_key(table) end tbl.print " create_table #{table.inspect}" if columns.detect { |c| c.name == pk } if pk != 'id' tbl.print %Q(, :primary_key => "#{pk}") end else tbl.print ", :id => false" end tbl.print ", :force => true" table_comment = @connection.table_comment(table) tbl.print ", :comment => '#{table_comment}'" unless table_comment.blank? tbl.puts " do |t|" # then dump all non-primary key columns 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 # AR has an optimization which handles zero-scale decimals as integers. This # code ensures that the dumper still dumps the column as a decimal. spec[:type] = if column.type == :integer && [/^numeric/, /^decimal/].any? { |e| e.match(column.sql_type) } 'decimal' else column.type.to_s end spec[:limit] = column.limit.inspect if column.limit != @types[column.type][:limit] && spec[:type] != 'decimal' spec[:precision] = column.precision.inspect if column.precision spec[:scale] = column.scale.inspect if column.scale spec[:null] = 'false' unless column.null spec[:default] = default_string(column.default) if column.has_default? spec[:comment] = '"' << (column.comment || '').gsub(/\"/, '\"') << '"' # ここでinspectを使うと最後の文字だけ文字化け(UTF-8のコード)になっちゃう (spec.keys - [:name, :type]).each{ |k| spec[k].insert(0, "#{k.inspect} => ")} spec end.compact # find all migration keys used in this table keys = [:name, :limit, :precision, :scale, :default, :null, :comment] & column_specs.map{ |k| k.keys }.flatten # figure out the lengths for each column based on above keys lengths = keys.map{ |key| column_specs.map{ |spec| spec[key] ? spec[key].length + 2 : 0 }.max } # the string we're going to sprintf our values against, with standardized column widths format_string = lengths.map{ |len| "%-#{len}s" } # find the max length for the 'type' column, which is special type_length = column_specs.map{ |column| column[:type].length }.max # add column type definition to our format string format_string.unshift " t.%-#{type_length}s " format_string *= '' column_specs.each do |colspec| values = keys.zip(lengths).map{ |key, len| colspec.key?(key) ? colspec[key] + ", " : " " * len } values.unshift colspec[:type] 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 adapter_name config = ActiveRecord::Base.configurations[Rails.env] config ? config['adapter'] : ActiveRecord::Base.connection.adapter_name end def mysql_views(stream) config = ActiveRecord::Base.configurations[Rails.env] view_names = @connection.select_values( "select TABLE_NAME from information_schema.TABLES where TABLE_TYPE = 'VIEW' AND TABLE_SCHEMA = '%s'" % config["database"]) view_names.each do |view_name| mysql_view(view_name, stream) end end def mysql_view(view_name, stream) ddl = @connection.select_value("show create view #{view_name}") ddl.gsub!(/^CREATE .+? VIEW /i, "CREATE OR REPLACE VIEW ") ddl.gsub!(/AS select/, "AS \n select\n") ddl.gsub!(/( AS \`.+?\`\,)/){ "#{$1}\n" } ddl.gsub!(/ from /i , "\n from \n") ddl.gsub!(/ where /i , "\n where \n") ddl.gsub!(/ order by /i , "\n order by \n") ddl.gsub!(/ having /i , "\n having \n") ddl.gsub!(/ union /i , "\n union \n") ddl.gsub!(/ and /i , "\n and ") ddl.gsub!(/ or /i , "\n or ") ddl.gsub!(/inner join/i , "\n inner join") ddl.gsub!(/left join/i , "\n left join") ddl.gsub!(/left outer join/i, "\n left outer join") stream.print(" ActiveRecord::Base.connection.execute(<<-EOS)\n") stream.print(ddl.split(/\n/).map{|line| ' ' << line.strip}.join("\n")) stream.print("\n EOS\n") end end end