},
					// hold `/` in case the entire path is removed
					Substitution: `/\2`,
				}
			} else {
				action.PrefixRewrite = uri
			}
		}
		if in.Rewrite.GetAuthority() != "" {
			authority = in.Rewrite.GetAuthority()
		}
	}
	if authority != "" {
		action.HostRewriteSpecifier = &route.RouteAction_HostRewriteLiteral{
			HostRewriteLiteral: authority,
		}
	}

	if in.Mirror != nil {