code: function knexMysqlKoa(options) {
    return function *knexMysqlKoa(next) {
      this.knex = knex(options);
      this.res.once("finish", done.bind(this, this.knex));
      yield next;
    };
  }
docs: Set a MySQL flavored Knex connection that can be accessed via Koa or Express middleware.
  
  @return {Function}
  Koa middleware.