DbIndexes - activerecord index handlier

db_indexes.rb

require(File.dirname(__FILE__) + '/../config/environment') unless defined?(Rails)

class DbIndexes
  
  def initialize(app, message = "Database Indexes")
    @app = app
    @message = message
  end

  def call env
    request = Rack::Request.new env
    status, headers, response = @app.call(env)
    begin
      table = request.params['table_name']
      column = request.params['column_name']
      act = request.params['act']

      if table and column
        index_workflow(act, table, column)
      end
    rescue
      response.body += 'Something wrong :('
    end
    body = request.xhr? ? response.body : response_body(response.body)
    [status, headers, body]
  end

  private

    def response_body(response)
      response += '<div id="dbIndexes">'
      response += '<h4 class="switcher">Tables indexes:</h4>
                   <dl class="area">'

      get_indexes.each{|obj|  response += "<dt>#{obj.table}</dt><dd>#{obj.name}</dd>"}
      response += '</dl>'
      response += '
        <h3 class="area"> Add/remove index </h3>
        <form method="get" action="" class="area">
          <input type="text" name="table_name" id="table_name"/>
          <input type="text" name="column_name" id="column_name"/><br />
          <input type="radio" name="act" value="create">Add<br />
          <input type="radio" name="act" value="destroy">Delete<br />
          <input type="submit" value="Do" name="commit"/>
        </form>'
        response += '</div>'

        response += '<script type="text/javascript">
          $("#dbIndexes > .area").hide();

          $("#dbIndexes > .switcher").click(function(){
            $("#dbIndexes > .area").toggle()
          }).css({"cursor":"pointer"});

          $("#dbIndexes").css({
            "margin": "5px",
            "padding": "10px",
            "border": "1px dotted blue",
            "width": "450px"
          });
          $("#dbIndexes >h4").css({
            "margin": "0"
          });
        </script>
        '
    end

    def get_indexes
      t = ActiveRecord::Base.connection.tables.\
        collect(&:to_sym).
        reject{|i| i.eql?(:schema_migrations) || i.eql?(:sessions)}
      i = t.collect{|i| ActiveRecord::Base.connection.indexes i}
      return i.reject!(&:blank?)[0]
    end


    def index_workflow(act, table_name, column_name)
      table = table_name.to_sym
      c = column_name
      column = c =~ /,/ ? c.split(', ').collect(&:to_sym) : c.to_sym

      if act.eql?('create')
        ActiveRecord::Migration.add_index(table,column)
      elsif act.eql?('destroy')
        ActiveRecord::Migration.remove_index(table,column)
      end
    end

end