[NIFI-5247] NiFi toolkit signal handling changes, Dockerfile enhancements

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.6.0, 1.7.0
• Fix Version/s: 1.7.0
• Component/s: Docker, Tools and Build
• Assignee: Unassigned
• Reporter: Peter Wilcsinszky
• Created: 29/May/18 07:30
• Updated: 01/Jun/18 17:23
• Resolved: 01/Jun/18 17:23

Description

1. Signal handling issues

In order for processes to handle signals properly in Docker we have to implement explicit signal handling for the first process in the container. In the case of the NiFi toolkit the easiest solution is to replace the bash shell with the Java process and let it handle the signal using the exec system call. More detailed explanation of the issue: http://veithen.github.io/2014/11/16/sigterm-propagation.html

Relevant issues: NIFI-3505 and NIFI-2689 that already added exec to the run invocation of the nifi.sh start script.

This changes makes stopping containers fast and graceful.

2. TLS toolkit commands and basic tooling in the container

In order to be able to request certificates from a running CA server instance some tooling is needed inside the container. These tools are openssl for checking ssl certificates and endpoints, and jq for config.json processing. A complete use case is available in the following NiFi helm chart: https://github.com/pepov/apache-nifi-helm/blob/master/templates/statefulset.yaml#L75

 

 

 

Issue Links

• links to: GitHub Pull Request #2746