code: func maybeEnterProjectNamespace(c context.Context, req proto.Message) (context.Context, error) {
  	if pbm, ok := req.(endpoints.ProjectBoundMessage); ok {
  		project := types.ProjectName(pbm.GetMessageProject())
  		log.Fields{
  			"project": project,
  		}.Debugf(c, "Request is entering project namespace.")
  		if err := coordinator.WithProjectNamespace(&c, project, coordinator.NamespaceAccessNoAuth); err != nil {
  			return c, err
  		}
  	}
  	return c, nil
  }
docs: // maybeEnterProjectNamespace enters a datastore namespace based on the request
  // message type.