Envoy sidecar example to do url rewrite

gistfile1.txt

# to test:
# curl http://envoy-test.apps.86cc.example.opentlc.com/config-server
# apache output:
# 127.0.0.1 - - [27/Feb/2020:01:33:48 +0000] "GET / HTTP/1.1" 403 3985 "-" "curl/7.29.0"
# 
# curl http://envoy-test.apps.86cc.example.opentlc.com/config-server/foo
# 127.0.0.1 - - [27/Feb/2020:01:35:58 +0000] "GET /foo HTTP/1.1" 404 196 "-" "curl/7.29.0"
# 
# curl http://envoy-test.apps.86cc.example.opentlc.com/config-server/foo/bar
# 127.0.0.1 - - [27/Feb/2020:01:36:35 +0000] "GET /foo/bar HTTP/1.1" 404 196 "-" "curl/7.29.0"
# 
# curl envoy-test.apps.86cc.example.opentlc.com/config-server/foo/bar/this/is/a/test?id=23566
# 127.0.0.1 - - [27/Feb/2020:09:04:03 +0000] "GET /foo/bar/this/is/a/test?id=23566 HTTP/1.1" 404 196 "-" "curl/7.29.0"
# 
# Template contents below.  To run "oc process -f filename.yaml | oc create -f -"
# If parameter override is needed, do the following:
# "oc process -f envoy-test.yaml NAMESPACE=foo WILDCARD_DNS=apps.example.com | oc create -f -"
# 
# 
apiVersion: v1
kind: Template
labels:
  template: "envoy-test-template"
metadata:
  name: envoy-test-template
  annotations:
    description: "Demo of envoy url rewriting"
    tags: "envoy"
objects:
- apiVersion: v1
  data:
    envoy.yaml: |
      static_resources:
        listeners:
        - address:
            socket_address:
              address: 0.0.0.0
              port_value: 8081
          filter_chains:
          - filters:
            - name: envoy.http_connection_manager
              config:
                stat_prefix: ingress_http
                route_config:
                  name: local_route
                  virtual_hosts:
                  - name: local_service
                    domains: ["*"]
                    routes:
                    - match: { prefix: "/config-server/" }
                      route: { prefix_rewrite: "/", cluster: local_service }
                    - match: { prefix: "/config-server" }
                      route: { prefix_rewrite: "/", cluster: local_service }
                    - match: { prefix: "/" }
                      route: { prefix_rewrite: "/", cluster: local_service }
                http_filters:
                - name: envoy.router
                http_filters:
                - name: envoy.router
                  typed_config: {}
        clusters:
        - name: local_service
          type: STRICT_DNS
          connect_timeout: 1s
          hosts:
          - socket_address:
              address: 127.0.0.1
              port_value: 8080
      admin:
        access_log_path: "/dev/null"
        address:
          socket_address:
            address: 0.0.0.0
            port_value: 8085
  kind: ConfigMap
  metadata:
    name: envoy-config
    namespace: "${NAMESPACE}"
    labels:
      app: envoy-test
- apiVersion: extensions/v1beta1
  kind: Deployment
  metadata:
    annotations:
      deployment.kubernetes.io/revision: "1"
    labels:
      app: envoy-test
    name: envoy-test
    namespace: "${NAMESPACE}"
  spec:
    progressDeadlineSeconds: 600
    replicas: 1
    revisionHistoryLimit: 0
    selector:
      matchLabels:
        app: envoy-test
    strategy:
      rollingUpdate:
        maxSurge: 25%
        maxUnavailable: 25%
      type: RollingUpdate
    template:
      metadata:
        labels:
          app: envoy-test
      spec:
        containers:
        - image: docker-registry.default.svc:5000/openshift/httpd
          imagePullPolicy: IfNotPresent
          name: httpd
          resources:
            limits:
              cpu: 200m
              memory: 200Mi
            requests:
              cpu: 100m
              memory: 100Mi
          terminationMessagePath: /dev/termination-log
          terminationMessagePolicy: File
        - image: envoyproxy/envoy-dev:d4533b6da770e1a1a90a7dd766a83d3f37d5d1d6
          imagePullPolicy: IfNotPresent
          name: envoy
          ports:
          - containerPort: 8081
            name: http
            protocol: TCP
          - containerPort: 8085
            name: http-admin
            protocol: TCP            
          resources:
            limits:
              cpu: 200m
              memory: 200Mi
            requests:
              cpu: 100m
              memory: 100Mi
          terminationMessagePath: /dev/termination-log
          terminationMessagePolicy: File
          volumeMounts:
          - mountPath: /etc/envoy
            name: envoy-config
        dnsPolicy: ClusterFirst
        restartPolicy: Always
        schedulerName: default-scheduler
        securityContext: {}
        terminationGracePeriodSeconds: 30
        volumes:
        - configMap:
            defaultMode: 420
            name: envoy-config
          name: envoy-config
- apiVersion: v1
  kind: Service
  metadata:
    labels:
      app: envoy-test
    name: envoy-test
    namespace: "${NAMESPACE}"
  spec:
    ports:
    - name: 8081-tcp
      port: 8081
      protocol: TCP
      targetPort: 8081
    - name: 8085-tcp
      port: 8085
      protocol: TCP
      targetPort: 8085
    selector:
      app: envoy-test
    sessionAffinity: None
    type: ClusterIP
- apiVersion: route.openshift.io/v1
  kind: Route
  metadata:
    labels:
      app: envoy-test
    name: envoy-admin
    namespace: "${NAMESPACE}"
  spec:
    host: envoy-admin.${WILDCARD_DNS}
    port:
      targetPort: 8085
    to:
      kind: Service
      name: envoy-test
      weight: 100
    wildcardPolicy: None
- apiVersion: route.openshift.io/v1
  kind: Route
  metadata:
    labels:
      app: envoy-test
    name: envoy-test
    namespace: "${NAMESPACE}"
  spec:
    host: envoy-test.${WILDCARD_DNS}
    path: /config-server
    port:
      targetPort: 8081
    to:
      kind: Service
      name: envoy-test
      weight: 100
    wildcardPolicy: None
parameters:
  - name: WILDCARD_DNS
    displayName: Wildcard DNS
    description: The wildcard dns entry for routes on this cluster
    required: true
  - name: NAMESPACE
    displayName: Target Namespace
    description: The target namespace for object creation
    required: true