How to add a condition to check a number of previous job chains for the execution of the current job chain

Scope

• Use Case
  • Make a job chain start at a certain point in time after an arbitrary number of other job chains completed successfully.
  • The predecessor job chains run in arbitrary sequence at arbitrary points in time.
• Example
  • Job Chain Z runs after 10 other job chains have completed.

Solution

• Download: final_chain.zip
• Extract the archive to a ./config/live/issues folder of your JobScheduler installation.
• The archive will extract the files to a sub-folder final_chain. 
• You can store the sample files to a any folder as you like, however, you will to adjust the job parameters accordingly.

Pattern

Implementation

Components

• The solution contains three job chains:
  • job_chain_A and job_chain_B represent the predecessor job chains.
  • job_chain_Z is the final job chain that checks if job_chain_A and job_chain_B have previously been executed successfully.
• The solution implements a job check_predecessor_job_chain_Z that has been added to the top of job chain_Z.
  • This job is parameterized with any number of parameters that start with the prefix "check_predecessor" and use an arbitrary suffix that is required in order to create unique parameter names. The value of each parameter is the final job of the respective job chain that is checked for successful execution:
    • Example
      • check_predecessor_A = issues/final_chain/do_something_job_chain_A
      • check_predecessor_B = issues/final_chain/do_something_job_chain_B
    • Should the sample files not have been extracted to the ./config/live/issues/final_chain folder then please adjust the parameter value to point to the respective directory.
  • This job implements a spooler_process() function that reads the parameters and checks the job history for successful execution of jobs as specified by the parameters.
  • Should all checks for previous successful execution provide a positive result, then the current order is moved to the next job chain node. Otherwise the current order is set back an will repeat several times depending on the setback configuration of this job.

Usage

• Positive Check
  • Add an order to job_chain_A by use of the JOC Add Order context menu.
    • The order should pass through the job chain without errors.
  • Add an order to job_chain_B by use of the JOC Add Order context menu.
    • The order should pass through the job chain without errors.
  • Add an order to job_chain_B by use of the JOC Add Order context menu.
• Negative Check
  • Modify the job do_something_job_chain_A to include an error, e.g. by adding the command exit 1 as the final line to the job script.
  • Add an order to job_chain_A.
    • The order should pass with an error.
  • Add an order to job_chain_Z
    • The order should pass with an error that is visible from the order log stating that the predecessor job did not complete successfully.
    • The order is set back and will repeat several times depending on the setback intervals that have been specified with the job check_predecessor_job_chain_Z.
  • Removing the modification to job do_something_job_chain_A and adding an order to job_chain_A that then runs successfully should result in a successful run of job_chain_Z.either by a new order added to job_chain_Z or by the next execution of the previous order that has been set back.