Unable to set sample_rate for nginx from v1.1.4 onward

[tahnik]

I am using nginx-opentracing with a nodejs backend. At first I tried v1.1.2 of dd-opentracing which uses the sample_rate in dd-config.json if the dd.priority.sample is set to false. However, it doesn't set any x-datadog- headers so the sample rate is not correctly propagated to the backend. From v1.1.4 onward, the backend does get the headers and it correctly uses the sample rate based on the sampling_rules. However, nginx traces stays 100%. So nginx is not caring about the sample_rate or sampling_rules. How do I control the nginx sample rate in that case?

I know it sounds like an nginx-opentracing issue but it seems to be originating from dd-opentracing so I am opening the issue here.

Thank you.