Configurare un servizio mesh di Envoy con file collaterale su GKE

Questa pagina descrive come configurare un mesh di servizi collaterali Envoy su con GKE.

Prerequisiti

Come punto di partenza, questa guida presuppone che tu abbia già:

Configura il servizio

Crea un servizio HTTP di esempio:

kubectl apply -f - <<EOF
kind: Namespace
apiVersion: v1
metadata:
  name: sidecar-example
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: whereami
  namespace: sidecar-example
spec:
  replicas: 2
  selector:
    matchLabels:
      app: whereami
  template:
    metadata:
      labels:
        app: whereami
    spec:
      containers:
      - name: whereami
        image: gcr.io/google-samples/whereami:v1.2.20
        ports:
        - containerPort: 8080
---
apiVersion: v1
kind: Service
metadata:
  name: whereami
  namespace: sidecar-example
spec:
  selector:
    app: whereami
  ports:
  - port: 8080
    targetPort: 8080
EOF

Crea un HTTPRoute di base per il servizio:

apiVersion: gateway.networking.k8s.io/v1beta1
kind: HTTPRoute
metadata:
  name: whereami-route
  namespace: sidecar-example
spec:
  parentRefs:
  - name: whereami
    kind: Service
    group: ""
  rules:
  - backendRefs:
    - name: whereami
      port: 8080
EOF

In alternativa, il seguente manifest descrive un servizio gRPC di esempio:

apiVersion: v1
kind: Service
metadata:
  name: sample-service
  namespace: sample-ns
  annotations:
    networking.gke.io/app-protocols: '{"50051": "HTTP2"}' # 50051 is backendref.port
spec:
  ports:
  - port: 50051
    targetPort: 50051

Configura il client

Crea un client:

kubectl apply -f - <<EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    run: client
  name: client
  namespace: sidecar-example
spec:
  replicas: 1
  selector:
    matchLabels:
      run: client
  template:
    metadata:
      labels:
        run: client
    spec:
      containers:
      - name: client
        image: curlimages/curl
        command:
        - sh
        - -c
        - while true; do sleep 1; done
EOF

Verifica che il pod client disponga automaticamente di un container collaterale Envoy inserito:
```
kubectl get pods -n sidecar-example -l run=client
```
L'output è simile al seguente:
```
NAME                    READY   STATUS    RESTARTS   AGE
client-xxxx             2/2     Running   0          20s
```
Attendi che il client sia pronto e che Status sia in esecuzione prima continua.

Verifica la configurazione del mesh di servizi collaterali di Envoy. Il seguente comando invia una richiesta al servizio whereami dal client

CLIENT_POD=$(kubectl get pod -n sidecar-example -l run=client -o=jsonpath='{.items[0].metadata.name}')

# The VIP where the following request will be sent. Because all requests
# from the client container are redirected to the Envoy proxy sidecar, you
# can use any IP address, including 10.0.0.2, 192.168.0.1, and others.
VIP='10.0.0.1'

TEST_CMD="curl -v -H 'host: whereami.sidecar-example.svc.cluster.local' $VIP"

kubectl exec -it $CLIENT_POD -n sidecar-example -c client -- /bin/sh -c "$TEST_CMD"

L'output è simile a questo:

< Trying 10.0.0.1:80...
< Connected to 10.0.0.1 (10.0.0.1) port 80 (#0)
< GET / HTTP/1.1
< Host: whereami
< User-Agent: curl/7.82.0-DEV
< Accept: */*
<
< Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< content-type: application/json
< content-length: 318
< access-control-allow-origin: *
< server: envoy
< date: Tue, 12 Apr 2022 22:30:13 GMT
<
{
  "cluster_name": "${CLUSTER_NAME}",
  "location": "${LOCATION}",
  "host_header": "whereami",
  ...
}