Handling global cache exceptions in a graphical data map

Add a Cache Failure transform to your Cache transform group to handle exceptions that might be raised as a result of a Cache transform.

Before you begin

You must complete the following task:

Create a graphical data map by using the Graphical Data Mapping editor. For information, see Creating a message map.
Add a Cache transform to the graphical data map; see Accessing a global cache by using a Mapping node.

About this task

If you want a graphical data map to handle exceptions that are returned as a result of a Cache transform, instead of stopping the map, you can add a Cache Failure transform to the Cache transform group. The Cache Failure transform is an optional transform in each of the Cache transform groups, and can be added or removed as required. If an exception is raised by the Cache transform, and you did not add a corresponding Cache Failure transform, the map operation is stopped and the exception is passed by the Mapping node to the message flow, where it can be caught by a TryCatch node or passed to the input node.

To add a Cache Failure transform to a Cache transform group by using the Graphical Data Mapping editor, complete the following steps:

Procedure

With a graphical data map (.map) file open in the Graphical Data Mapping editor, right-click a Cache Put, Cache Get, or Cache Remove transform, and then select Cache > Failure.

Note: You can also add a Cache Failure transform by placing the mouse over the Cache transform and selecting the Cache Failure icon ().

A Cache Failure transform is added to your Cache transform group.
Connect the Cache Failure transform to specify how any exceptions from the Cache transform are processed when the map is run. If the Cache Failure transform is present and is connected to one or more output objects, then the exception is caught and processed by the Cache Failure transform.
Important: If the Cache Failure transform is present but is not connected, the following actions are taken:
- The exception is caught by the Cache Failure transform and is ignored.
- The map is marked with a warning.
Double-click the Cache Failure transform to open the nested map and further define the transform. For more information, see Cache Failure.

Results

You added a Cache Failure transform to a Cache transform group in your graphical data map and configured the Cache Failure transform to handle exceptions that are returned by the Cache transform. If you want the execution of the map to stop when the Cache transform receives an exception, remove the Cache Failure transform from the Cache transform group.