Merge Task Variables - Null vs. Undefined

Breaking Change Notice (2023.2.0)

This breaking change notice applies to the 2023.2 IAP release.

Use of Null and Undefined Values in Merge & Child Job Tasks

In the 2023.2 feature release, Itential has standardized how jobs compile and handle task variables at runtime. This change not only allows users to identify the true inputs and outputs to a task, but affects how IAP decodes inputs for the merge and childjob task at runtime.

Beginning with the 2023.2 IAP release, the merge task now returns a value of null when there is an "Undefined Key in Task with Multiple Outputs (JST Task)", and undefined is now returned when a Child Job Task has an "Undefined Job Variable"

Depending on the version from which you are migrating will determine if there is a breaking change in your workflow. Please consult the matrix tables in past release versions to determine what changes you need to make.

What should I do?

Since the use of null or undefined is not recommended in workflow design, this breaking change notice will not apply to everyone.

For those who do utilize null or undefined in their worklows, it is important to know that different task types will determine how null or undefined values are treated. The matrix (table) below outlines the expected result for several tasks, including the merge task.

• Step 1: Choose the undefined scenario listed in the top-most header row and the outgoing task type listed in the first column.
• Step 2: Move along the row of the task type and down the column of the scenario.
• Step 3: The entry where the two meet is how it resolves the input for the task. For example, Merge Task × Undefined Task Input = null.

Related Reading

• Null vs. Undefined in Workflows