Cloned from launchpad blueprint https://blueprints.launchpad.net/glance/+spec/cross-service-request-id.

Description:

Create a unified request identifier associated with an API request that crosses OpenStack service boundaries. This will enable more effective debugging of requests that span multiple services. For example, a Nova instance create request may touch other services including Glance. A single id will simplify the process of tracking down errors.

See related email discussion: https://lists.launchpad.net/openstack/msg13082.html

Proposal:
-The first OpenStack service to touch a request will tag it with a "correlation_id". This will effectively be a global identifier. Inter-service requests will contain this ID in an HTTP header, "X_CORRELATION_ID". This value will be a UUID.

-Each service that touches the request will carry along this header value and use it in log messages and external notifications.

-Each service may have its own internal request identifier (request_id in Nova and Glance) and should also log this value in conjunction with the global identifier.

Question - How to guard against users supplying their own request id value? Check for uniqueness? Only accept request ID headers from certain source IPs?

Refer to https://blueprints.launchpad.net/nova/+spec/cross-service-request-id for further discussions.

Specification URL (additional information):

None