Task failure handler || XebiaLabs documentation

Valid since:
XL Release 8.1.0

As of XL Release 8.1.0 a new property was added on the task level called Handling failure. This means that you can enable failure handling on any task in a phase. You can use this to execute a Jython script when the task fails its execution or just to skip the task.

Task attachments

Skip task: If the task fails, it is automatically skipped.
Define additional action: This option allows you to write your own Jython script to be executed if the task is going to fail. You can also use a script to do a clean up, retry, or conditionally skip or fail a task.

Scripts

Important: Modification of a task status, such as: skip task, retry task, or other outcomes, must be the last line of your script.

If you do not modify the task status in your script, the task will be in the failed state after the script has run.

The script will run until it finishes or until the timeout is reached. You can modify the duration of the timeout in conf/xl-release.confby changing this property:

      xl.timeouts.failureHandlerTimeout=60 seconds

If the handler script produces an error or a time out occurs, the task will be marked as failed.

While the failure handler script is running, you can manually abort the task by clicking on the right of the task, and selecting Abort.

Script examples

These are some examples of how you can use the Handling failures feature.

Retry a task a number of times

If your release process contains a third party dependency that is error prone and the task must be retried before you can conclude if something is broken:

Create a release variable of type Number, named attempt, and set the default value to 0.
Set the operation to Define additional action.
Set the following script:

if (releaseVariables['attempt'] < 3):
  releaseVariables['attempt'] = releaseVariables['attempt'] + 1
  taskApi.retryTask(getCurrentTask().getId(), "Retrying task from failure handler.")
else:
  taskApi.skipTask(getCurrentTask().getId(), "Skipped task from failure handler.")

Set a variable to be used on a precondition

Depending on the status of a tasks, you can execute or skip the subsequent task or group of tasks by setting the value of a variable and using it in a precondition:

Create an executeTask variable of type Boolean with the default value set to True (click on checkbox).
Set the operation to Define additional action.
Configure the script:
- If the first task fails and you want to skip the subsequent task, set the following script:
```
releaseVariables['executeTask'] = False
```
- If the first task fails and you want to execute the subsequent task, set the following script:
```
releaseVariables['executeTask'] = True
```
Set the precondition on a task or task group: ${executeTask}.

Skip a phase in advance

You can skip a complete phase if an error occurred in previous phases:

Set the operation to Define additional action.
Set the following script:

thisTask = getCurrentTask()
nextPhase = phaseApi.searchPhasesByTitle("next phase", getCurrentRelease().id)[0]
for t in nextPhase.tasks:
  taskApi.skipTask(t.id, "Skipped from failure handler.")
taskApi.skipTask(thisTask.id, "Skipped task from failure handler.")

Disabling the feature

If you want to disable this feature for a specific type of task, add the following line to the conf/deployit-defaults.propertiesfile:

  xlrelease.GateTask.failureHandlerEnabled=false

This snippet sample disables Handling failures for the Gate Task.

To disable this feature for all task types, add the following line to conf/deployit-defaults.propertiesfile:

  xlrelease.Task.failureHandlerEnabled=false

This snippet sample disables Handling failures for all task types.

Important: The code provided in this topic is sample code that is not officially supported by XebiaLabs. If you have questions, please contact the XebiaLabs support team.