Monitors

Introduction

The Monitors (also called Pre-/Post-Processing Monitors) are used with Jobs to provide pre-processing and post-processing capabilities by scripting. The pre-/post-processing monitors are executed before a task is being executed by the JobScheduler. Similarly the post-processing monitors are executed once a task is completed. 

• A job can have multiple Pre-/Post-Processing Monitors ordered starting from 0 onward to be executed by the JobScheduler.
  • A Pre-Processing Monitor can be created to 
    • validate required conditions for a particular task to be started or 
    • set a parameter value dynamically, e.g. today's date.
  • At the same time a Post-Processing Monitor can check the job's execution status, return code, total execution time etc..
• The Pre-/Post-Processing Monitors can be programmed independent from the job's programming language e.g. a Shell script job can have a Pre-/Post-Processing Monitor written in JavaScript. 

Scripted Conditions

• The scripts can include
  • Java classes
  • JavaScript code
• Scripted conditions are a powerful means for flexibility:
  • JavaScript code can be added directly to Jobs and Monitors and is interpreted at run-time. No build cycle is required.
  • Java classes can be added that make use of of the ecosystem of available Java libraries.
• The JobScheduler exposes its objects, methods and properties by use of the API Interface.
  • Find details and examples with the Reference Documentation.
• Scripted conditions can be applied by implementing a spooler_process_before() function for a preprocessor monitor with jobs in a job chain that will
  • return the value true if the job should start,
  • return the value false if the job should not start,
  • move Orders to the next state in a job chain if the current job should be skipped

See also

• How to configure a named monitor
• How to configure an enforced monitor
• How to add conditions for job execution with date calculation