grpc-web連接阿里雲ASM（isito 1.6）配置

參照 https://github.com/istio/istio/pull/10064

grpc-web連接ASM需要兩步

1、配置 Service的端口名爲grpc-web前綴，使istio可識別爲grpc-web服務

apiVersion: v1
kind: Service
metadata:
  labels:
    app: iam-pod
  name: iam-svc
  namespace: release
spec:
  ports:
    - name: grpc-web-port
      port: 10010
      protocol: TCP
      targetPort: 10010
  selector:
    app: iam-pod

2、配置 VirtualService 的corsPolicy屬性

需注意在istio1.6中需設置allowOrigins: - regex: .* 而不是 allowOrigin: - "*"

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: api-vsvc
  namespace: release
spec:
  gateways:
    - api-gateway
  hosts:
    - '*'
  http:
    - corsPolicy:
        allowCredentials: true
        allowHeaders:
          - grpc-timeout
          - content-type
          - keep-alive
          - user-agent
          - cache-control
          - content-type
          - content-transfer-encoding
          - custom-header-1
          - x-accept-content-transfer-encoding
          - x-accept-response-streaming
          - x-user-agent
          - x-grpc-web
          - device-tag
          - token
        allowMethods:
          - POST
          - GET
          - OPTIONS
          - PUT
          - DELETE
        allowOrigins:
          - regex: .*
        exposeHeaders:
          - custom-header-1
          - grpc-status
          - grpc-message
        maxAge: 1728s
      match:
        - port: 8080
      route:
        - destination:
            host: iam-svc
            port:
              number: 10010