Vector: Prometheus sink doesn't bind/listen until it receives events

[rrichardson]

vector 0.11.0 (gb031ead x86_64-unknown-linux-gnu 2020-09-30) 
(Current master as of 2020-09-30) 

Vector Configuration File

[sinks.prometheus]
  type = "prometheus"
  inputs = ["log_to_metric"] # required
  address = "0.0.0.0:9091" # required
  namespace = "vector" # required

Expected Behavior

Vector should begin listening on port 9091 for inbound requests from prometheus.

Actual Behavior

Vector does not begin listening on port 9091 for inbound requests from prometheus.

Additional Context

Looking at the code that was refactored 3 days ago, the start_server_if_needed() function is now executed at the top of a while loop that is processing incoming events.
I think it should be at the top of the

References

The change was made here:

3933

[rrichardson]

Note that if a prometheus sink receives events consistently, it might not experience this problem. However, I am running vector as a daemonset in k8s, and, in some cases, it won't be running on the same node as the services which generate logs which spawn these events. So what I get is Prometheus alerting me in the middle of the night that some of it's endpoints cannot be scraped.