Lifecycle Hooks

Sometimes it's necessary to trigger specific pipeline actions at certain times during pipeline execution. For example, if you wanted to send multiple notification types after a particular pipeline step or at the conclusion of a pipeline if the build was failure.

JTE supports this type of Aspect Oriented Programming style event handling through annotation markers that can be placed on methods defined within Library Steps.

Hook Types

The following lifecycle hook annotations are available:

Annotation	Trigger
@Validate	Beginning of a Pipeline Run, before the Pipeline Template
@Init	After all @Validate hooks, before the Pipeline Template
@BeforeStep	During template execution, before every Library Step
@AfterStep	During template execution, after every Library Step
@CleanUp	After template execution
@Notify	During template execution after every Library Step and after template execution

Hook Context

Lifecycle Hook annotations can be placed on any method inside a step.

Every step has an autowired hookContext variable which provides steps with relevant information about what triggered the hook.

Property	Type	Description
library	String	The library that contributed the step that triggered the Lifecycle Hook. Is null when the Lifecycle Hook wasn't triggered by a step.
step	String	The name of the Library Step that triggered the Lifecycle Hook. Is null when the Lifecycle Hook wasn't triggered by a step.
methodName	String	The name of the method within the step that was invoked to trigger the Lifecycle Hook. Is null when the Lifecycle Hook wasn't triggered by a step.
exceptionThrown	Boolean	When the hook is triggered by a step, this refers to if the step triggering step threw an exception. When the hook is triggered by template completion, refers to if there is an uncaught exception that will fail the pipeline.

Conditional Hook Execution

Sometimes you'll only want to invoke the Hook when certain conditions are met, such as a build failure or in relation to another step (like before static code analysis).

Each annotation accepts a Closure parameter. If the return object of this closure is truthy then the hook will be executed.

While executing, the code within the Closure parameter will be able to resolve the hookContext variable, the library configuration of the library that loads the step via the config variable, and the currentBuild variable made available in Jenkins Pipelines.

Example Hook Usage

library_step.groovy

@BeforeStep({ hookContext.step.equals("build") })
void call(){
  // execute something right before the Library Step called build is executed.
}

Note

The closure parameter is optional. If omitted, the hook will always be executed.