Feature Request: Allow the client to specify the X-Request-Id header for correlating requests across services

[timhallinflux]

Feature Request

Proposal:
InfluxDB logs requests with a correlation Id and returns the correlation Id to the client in the Request-Id HTTP header for correlating requests and responses.

For example, an HTTP GET on http://localhost:8086/ping results in a log message like the following:

[httpd] 172.17.0.1 - - [19/Jul/2017:18:38:08 +0000] "GET /ping HTTP/1.1" 204 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36" 68beb75a-6cb1-11e7-8001-000000000000 1811

The correlation Id 68beb75a-6cb1-11e7-8001-000000000000 is returned in the Request-Id header.

To track requests across disparate services, it would be ideal if InfluxDB honored the X-Request-Id header so that the caller could pass a correlation Id as part of the request. If the header exists, use this correlation Id for logging and the Request-Id header in the response. If it does not exist, generate the correlation Id for the request as it is done now.

Current behavior:
X-Request-Id cannot be specified by the caller.

Desired behavior: [What you would like to happen]
Allow X-Request-Id to be sent by the caller and return it in the Request-Id header in the response.

Use case:
Required for correlating service-to-service calls when building applications which leverage InfluxDB