Add helm deployments and a Makefile for the ExternalName example/test.

examples/externalname/values.yaml

+apps:
+  coffee-external:
+    externalName: coffee-svc.default.svc.cluster.local
+    config:
+      # For requests routed to coffee-external-svc:
+      # - The first byte timeout is three seconds.
+      # - The between bytes timeout is two seconds.
+      first-byte-timeout: 3s
+      between-bytes-timeout: 2s
+      probe:
+        # Health probe for coffee-external-svc:
+        # - Requests are send as shown in the request array.
+        # - Timeout three seconds.
+        # - Three of four good probes are required for the Endpoint to
+        #   count as healthy.
+        request:
+        - GET /coffee/healthz HTTP/1.1
+        - "Host: cafe.example.com"
+        - "Connection: close"
+        timeout: 3s
+        interval: 3s
+        window: 4
+        threshold: 3
+        initial: 3
+      # Configuration specific to ExternalName Services
+      dnsRetryDelay: 25s
+      domainUsageTimeout: 3h
+      firstLookupTimeout: 20s
+      resolverTimeout: 1m
+      resolverIdleTimeout: 10m
+      maxDNSQueries: 200
+
+  tea-external:
+    externalName: tea-svc.default.svc.cluster.local
+    servicePort: 81
+    targetPort: 80
+    config:
+      # For requests routed to tea-external-svc:
+      # - The Host header is set to cafe.example.com if it is missing from
+      #   the request.
+      # - The connect timeout (for opening new connections to an Endpoint)
+      #   is one second.
+      # - The first byte timeout (until the first byte of a backend response
+      #   header is received) is two seconds.
+      # - The between bytes timeout (while a response is being received)
+      #   is one second.
+      # - No more than 200 connections to an Endpoint may be opened.
+      host-header: cafe.example.com
+      connect-timeout: 1s
+      first-byte-timeout: 2s
+      between-bytes-timeout: 1s
+      max-connections: 200
+      probe:
+        # Health probe requests for Endpoints of tea-external-svc:
+        # - Request URL path is /tea/healthz
+        # - Health probes are good when the response code is 200.
+        # - Five second timeout to receive responses.
+        # - Probes are sent every five seconds.
+        # - Two of three probes must be good for the Endpoint to count as
+        #   healthy.
+        # - At startup, one probe is implicitly assumed to be good.
+        url: /tea/healthz
+        expected-response: 200
+        timeout: 5s
+        interval: 5s
+        initial: 2
+        window: 3
+        threshold: 2
+      # Configuration specific to ExternalName Services:
+      # - dnsRetryDelay (VCL duration): delay until a DNS lookup is retried
+      #   after a lookup gets negative results. Default 30s
+      # - domainUsageTimeout (VCL duration): delay until an unused domain
+      #   and its backends are removed. Default 2h
+      # - firstLookupTimeout (VCL duration): delay until a lookup is failed
+      #   when a domain is requested the first time and there is no response
+      #   from the name service. Default 10s
+      # - resolverTimeout (VCL duration): timeout for DNS lookups
+      # - resolverIdleTimeout (VCL duration): timeout for idle DNS connections
+      #   (no outstanding responses and no pending queries)
+      # - maxDNSQueries (integer >= 0 and <= 65535): maximum number of
+      #   outstanding DNS queries. Queries above the limit are queued.
+      # - followDNSRedirects (boolean): whether DNS queries follow redirects
+      #   (CNAME and DNAME). Default true
+      dnsRetryDelay: 20s
+      domainUsageTimeout: 1h
+      firstLookupTimeout: 15s
+      resolverTimeout: 45s
+      resolverIdleTimeout: 5m
+      maxDNSQueries: 100
+      followDNSRedirects: true
+
+  coffee:
+    image: nginxdemos/hello:plain-text
+    replicas: 2
+    labels:
+      app: coffee
+      example: externalname
+
+  tea:
+    image: nginxdemos/hello:plain-text
+    replicas: 3
+    labels:
+      app: tea
+      example: externalname
+
+ingress:
+  name: cafe-ingress
+  rules:
+  - host: cafe.example.com
+    paths:
+    - path: /tea
+      app: tea-external
+      servicePort: 81
+    - path: /coffee
+      app: coffee-external