[NIFI-3763] Add new processor to log user defined messages built with NiFi Expression Language

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.3.0
• Component/s: Core Framework
• Assignee: Unassigned
• Reporter: Peter Horvath
• Created: 01/May/17 19:04
• Updated: 15/May/17 19:22
• Resolved: 15/May/17 19:22

Description

Sometimes it would be very useful to have a NiFi processor, which can simply log messages as defined by the DataFlow Manager (DFM/operator).

Such functionality would be a powerful aid for debugging running NiFi dataflows. The DFM should be able to specify the single line log message using NiFi Expression Language. Similarly to the existing LogAttribute processor, the DataFlow Manager should be able to specify the log level (trace, debug, info, warn, error) at which the log line is written.

While the functionality can be achieved by combining UpdateAttribute and LogAttribute processor nodes, having to use three separate nodes (adding the log message as an attribute, logging the attribute, then removing the attribute from the flowfile's processing context) and a temporary attribute to convey the message is overly complex and clutters the flow diagram.

Issue Links

• links to: GitHub Pull Request #1737