データベース定義書を作るタスク(rails用)

dbdoc.rake

require 'rake'

Table  = Struct.new(:name, :comment, :columns, :indexes)
Column = Struct.new(:name, :type, :not_null, :default, :primary_key, :comment)
Index  = Struct.new(:name, :columns, :primary, :unique)

def get_schema_info(klass)
  table = Table.new
  table.name = klass.table_name
  table.columns = []
  table.indexes = []
  table.comment = klass.connection.retrieve_table_comment(klass.table_name) if defined? MigrationComments

  column_comments = (defined? MigrationComments)? klass.connection.retrieve_column_comments(klass.table_name) : {}
  cols = klass.columns
  cols.each do |col|
    column = Column.new
    column.name        = col.name
    column.type        = col.sql_type.to_s
    column.default     = klass.column_defaults[column.name] unless col.default.nil? || column.type == "jsonb"
    column.not_null    = col.null
    column.primary_key = (klass.primary_key && (klass.primary_key.is_a?(Array) ? klass.primary_key.collect{|c|c.to_sym}.include?(col.name.to_sym) : col.name.to_sym == klass.primary_key.to_sym))
    column.comment     = column_comments[col.name.to_sym]
    table.columns << column
  end

  indexes = klass.connection.indexes(klass.table_name)
  indexes.sort_by{|index| index.name}.each do |idx|
    index = Index.new
    index.name = idx.name
    index.columns = idx.columns.join(',')
    index.unique = idx.unique
    table.indexes << index
  end

  table
end
task dbdoc: :environment do
  klasses = Dir["app/models/**/*.rb"].
    reject{|f| f["concerns/"] }.
    map{|f| f.gsub(/^app\/models\/(.+?)\.rb$/, '\1') }.
    map{|m| ActiveSupport::Inflector.camelize(m) }.
    map{|k| ActiveSupport::Inflector.constantize(k) }
  datum = klasses.map{|k| get_schema_info(k) }

  package = Axlsx::Package.new
  styles = package.workbook.styles
  title  = styles.add_style(bg_color: 'c0c0c0', b: true, font_name: 'MS P Gothic')
  header = styles.add_style(bg_color: 'c0c0c0', b: true, font_name: 'MS P Gothic', font_size: 'large')
  cols   = styles.add_style(font_name: 'MS P Gothic')
  #sheet = package.workbook.add_worksheet(name: 'テーブル一覧')
  datum.each do |table|
    sheet = package.workbook.add_worksheet(name: table.name)
    sheet.add_row(['テーブル情報'], style: title)
    sheet.add_row([])
    sheet.add_row(['テーブル名', '備考'], style: header)
    sheet.add_row([table.name, table.comment], style: cols)
    sheet.add_row([])
    sheet.add_row(['カラム情報'], style: title)
    sheet.add_row([])
    sheet.add_row(['No', 'カラム名', 'データ型', 'Not Null', 'デフォルト値', '備考'], style: header)
    table.columns.each_with_index do |col, idx|
      sheet.add_row([idx + 1, col.name, col.type, col.not_null, col.default, col.comment], style: cols)
    end
    sheet.add_row([])
    sheet.add_row(['インデックス情報'], style: title)
    sheet.add_row([])
    sheet.add_row(['No', 'インデックス名', 'カラム', 'ユニーク'], style: header)
    table.indexes.each_with_index do |index, idx|
      sheet.add_row([idx + 1, index.name, index.columns, index.unique], style: cols)
    end
  end

  package.serialize('データベース定義書.xlsx')
end