[NIFI-9483] Evaluate Addition of log4j-to-slf4j

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.16.0, 1.15.2
• Component/s: Extensions
• Assignee: David Handermann
• Reporter: David Handermann
• Created: 13/Dec/21 23:07
• Updated: 20/Dec/21 17:43
• Resolved: 20/Dec/21 17:03

Description

Several extension components include transitive dependencies on Log4j 2. NiFi uses the SLF4J API for logging in application code, and Logback as the runtime implementation. 

The Log4j 2 system supports SLF4J for runtime message routing, which would ensure that all log messages route through SLF4J and Logback, as opposed to falling back to the default Log4j 2 appender.  Current extension components should be evaluated to determine whether an explicit dependency on log4j-to-slf4j is necessary to ensure proper runtime log handling for libraries that rely on the Log4j 2 API.

Issue Links

• links to: GitHub Pull Request #5616