The NiFi EvaluateJsonPath processor lets you specify a JSON path, which will be applied to the content of a flow file. For most situations that works great, but what if you want to retrieve a value where the property you want to read depends on a flow file attribute? EvaluateJsonPath doesn’t support the expression language on dynamic attributes. Use an ExecuteScript processor instead.
We can load data into a data hub from a variety of upstream data sources. What if we want to delete documents that have been deleted upstream? In the ideal case we’re using a Change Data Capture system and we get notifications about those deletions, but sometimes we don’t have that. How can we detect what’s been deleted if we don’t get notified?