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Introduction
Assume Consider the following scenario:
- A number of jobs are executed in sequence.
- If one or more jobs fail with exit return code 1 then the these jobs should be repeated for a number of times. For any other non-zero exit return codes, the order should be put to a failed state and should wait for user intervention, for example to resume or to cancel the failed order.
- A related scenario is described in the JS7 - How to retry a job and to catch specific exit codes article.
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Solution
The workflow below workflow implements the use case from the usnig the following instructions:
Download (.json upload): retry-on-return-code.workflow.json
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Explanation:
- This workflow implements:
- an outer Retry Block to repeat execution,
- an inner Job Instruction that fails with varying return codes,
- an inner If Instruction to decide about the handling of specific return codes.
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The job is implemented to complete with varying return codes that which are handled like this:
Explanation:
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- Within the Retry Block the JS7 - If Instruction is used to check the return code value, This value is available from with the built-in
$returnCode
variable. - The first If Instruction excludes by use of uses the
$returnCode != 0
predicate that to exclude any successful orders are excluded from the nested If Instruction. For details about predicates, see JS7 - Expressions for Variables. - The second If Instruction determines the error handling by use of using the
$returnCode == 1
predicate:- if the return code value is 1 then the left branch (true) of the If Instruction is used,
- for any other return code values the right branch (false) is used.
- Subsequently we find two occurrences of a JS7 - Fail Instruction.
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- The left Fail Instruction fails the order with a return code value 1.
- In addition, a message can be is added that becomes visible with the JOC Cockpit GUI for the failed order.
- As a consequence the failed order is immediately picked up by the outer Retry Instruction that will repeat execution of
job1
having applied the indicated delay.
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- The right Fail Instruction fails the order with a return code value 2.
- In addition, a message can be is added that becomes visible with the JOC Cockpit GUI for the failed order.
- The
uncatchable
checkbox is used to indicate that the failed order cannot be picked by the outer Retry Instruction. Instead, the order will remain with its current position in a failed state and waits for user interventionwait for user intervention.
Implications
In this scenario the job is configured to consider return codes 1 and 2 as signaling success. This allows the return code to be checked and appropriate action to be taken by either failing or retrying order execution.
At the same time this implies that the job is not considered to have failed. As a result:
- the JS7 - Task History classifies the job being successfully executed,
- a JS7 - Notifications will neither be created nor visible in the JS7 - Monitor view.
These implications might reflect what some users need. For an alternative solution that fails the offending job and that creates notifications see JS7 - How to retry a job and to catch specific exit codes.