Story #13790

Updated by Peter Amstutz about 2 years ago

Record time to first byte for:

* all
Report latencies for requests
* by requests forwarded to local Rails API server
* by requests that involve contacting federated clusters (parameterize by remote?)
* by requests served directly from postgres by controller (do we have any that do that yet?)
* by HTTP method
* by endpoint (/arvados/v1/collections, /arvados/v1/containers etc)
* by result (200, 404, etc)

Use prometheus client for Go.