[NIFI-7922] Add support for GET request in ListenHTTP for health check

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.13.0
• Component/s: Extensions
• Assignee: Peter Gyori
• Reporter: Peter Gyori
• Created: 14/Oct/20 14:08
• Updated: 16/Dec/20 19:11
• Resolved: 16/Nov/20 11:24

Description

Add support for GET request in ListenHTTP processor, so that when put behind a load balancer, the LB can make a health check to verify that the service is available.
The health check service should be available on <ListenHTTP_service_URI>/healthcheck.
It should be available via the listening port specified in the processor's property, but it should optionally be configured to be available on a different port.
Accessing the health check service via a dedicated port should use 1-way SSL at most, even if the main service uses 2-way SSL, since some load balancers do not support client certificate handling:
 - If the processor is set not to use SSL, SSL should not be used on the health check port, either.
 - If the processor is set to use one-way SSL, one-way SSL should be used on the health check port.
 - If the processor is set to use two-way SSL, one-way SSL should be used on the health check port.

Issue Links

• links to: GitHub Pull Request #4603