istio virtualservice：使用正则过滤流量

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: query-ip
spec:
  hosts:
  - "*"
  gateways:
  - bookinfo-gateway
  http:
  - match:
    - headers:
        user-agent:
          regex: .*(?i)(curl|python|go|java|javascript|php|ruby|perl).*
    route:
    - destination:
        host: query-ip.query-ip.svc.cluster.local
        port:
          number: 1080 ## service port     
  - match:
    - headers:
        user-agent:
          prefix: git
    route:
    - destination:
        host: gitbook.default.svc.cluster.local
        port:
          number: 10080 ## service port