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Events

Question: How can I wait for an event in a job chain?

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• Unzip all files of test_event.zip into the ./config folder of your active instance of the eventservice JobScheduler installation. After unzipping you will have all the objects needed to run the example in the live/test_events subfolder.
• Open the JS operations gui for the workload JobScheduler in your browser using http://scheduler_host:scheduler_port
• Find the {{test_event/job chain_example_wait_for_event }} job chain and click on it.
• Click in the job chain menu on "add order"
• You see the order will run until the step 3 is reached. As the EVENT event does not exist, the order will wait for 10s and then check again.
• Switch to the tab Jobs.
• Find the {{test_event/job_event_add }} job chain and click on it.
• In the Job menu press Start task immediately. This will create the EVENT event.
• Switch to the tab Job Chains.
• See the order proceeding with execution of the next step

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The test_event/job chain_example_wait_for_event }} event job chain has 2 dummy steps and the wait for event step. This step executes the {{ test_event/job_event_check job to look for the desired event specified in the scheduler_event_spec parameter. As the events are stored in a xml object you have to specify a xpath expression here.

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The test_event/job chain_example_wait_for_event_db }} db  job chain has 2 dummy steps and the wait for event step. This step executes the {{ test_event/job_event_check_db job to look for the desired event. The difference to to first example is, that this job uses the events database. You can either specify parameters for event_id, event_class and exit_code to test for a specific event or you can specify a condition for the events you are waiting for.

example:

 class_a.event_1:99 and not (class_b.event2 or class_b.event3)
  
 if the event_1 in class class_a exists with exit_code=99 and event2 and event3 from class_b do not exist, this expression evaluates to true.

You also can specify how to handle the existing or not existing of events with the paramters handle_existing_ah1. "error|success" or handle_not_existing_as"error|success"

example

 handle_existing_as=error will wait until the events do not exist

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