API job_chain object should provide methods to retrieve orders

Current Situation

• The API provides no possibility to retrieve orders from job chains.

Workaround

• Use of the XML command <show_job_chain/> to retrieve the orders of a job chain.
• Use of the XML command <modify_order/> to change order attributes and e.g. to start an order via <modify_order at="now"/>

Desired Situation

• Retrieve orders from a job chain:

   
  // use current job chain
  var job_chain = spooler_task.order.job_chain;
  // alternatively use any other job chain
  // var job_chain = spooler.job_chain("/my_chain");
  // retrieve list of orders
  var orders = job_chain.get_orders();
  for ( var i=0; i < orders.length; i++ ) {
    if( orders[i].id != spooler_task.order.id ) {
      orders[i].suspended = true;
    }
  }
  

• Retrieve specific order from a job chain:

  var job_chain = spooler.job_chain("/my_chain");
  var order = job_chain.get_order("my_order");
  

Maintainer Notes

• Modifications to an order that is not handled by the current task are not persistent, i.e. they will be lost in case of a JobScheduler restart. Therefore we will not develop this feature for the JobScheduler API.
• Instead, this feature will be resumed for use with Web Services.