I have started Apache NiFi in a container successfully with the command
docker run --name nifi -p 9090:9090 -d -e NIFI_WEB_HTTP_PORT='9090' apache/nifi:latest
and can connect to the UI on `http://localhost:9090/nifi` - however, my company only allows HTTPS connections between subnets and so I am using Nginx to reverse proxy the https calls to the NiFi container with the following config:
When I browse to `https://mercury-dev/nifi` from a remote machine, the NiFi UI starts to load, and then fails. The on-screen error says `An unexpected error has occurred. Please check the logs for additional details.` and the Chrome developer console reports:
/nifi-api/access/kerberos:1 Failed to load resource: the server responded with a status of 409 (Conflict)
/nifi-api/access/oidc/exchange:1 Failed to load resource: the server responded with a status of 409 (Conflict)
/nifi-api/flow/about:1 Failed to load resource: the server responded with a status of 500 (Internal Server Error)
/nifi-api/flow/process-groups/root:1 Failed to load resource: the server responded with a status of 500 (Internal Server Error)
When I log into the container and look at the log files, I see a number of errors saying, for example ERROR [NiFi Web Server-21] org.apache.nifi.web.util.WebUtils The provided context path [/nifi-api] was not whitelisted
I have found references in the NiFi documentation to whitelisting the host and content using the `nifi.web.proxy.host` and `nifi.web.proxy.context.path` properties, but I can't find description of how to do it.
Within the container there is no editor available to edit the properties file (and anyway, it's really bad practice)
The documentation mentions setting them through the Global menu on the UI, but I see no obvious option to do this.
I may be able to supply environment variables to the container command line, but can't find any reference to doing this and therefore what variable names to use.
How can I set these properties, or otherwise get this container running behind the HTTPS proxy?