Exercise_5.07

Assignment

Make the Ping-pong application serverless.

Reading this might be helpful.

TIP: Your application should listen on port 8080 or better yet have a PORT environment variable to configure this.

Solution

Binaries

Pingpong

• Application was modified by adding introducing a PING_PORT environment variable to start the application on. Source code can be found here.
• Image was pushed to Docker Hub repo viksil/pingpong:5.07.

Log output

• Application was modified by adding introducing a LOG_PORT environment variable to start the application on. Source code can be found here.
• Image was pushed to Docker Hub repo viksil/log_output:5.07.

Log reader

• Application was modified by adding introducing a READ_PORT environment variable to start the application on. Source code can be found here.
• Image was pushed to Docker Hub repo viksil/log_output_reader:5.07.

Manifests

Postgres

• Unchanged manifests from Exercise 2.07 were used, since serverless services are stateless, but postgres database must be deployed as a StatefulSet.

Pingpong

• Service and Deployment manifest were merged into a Knative Service manifest.
• spec.template.spec.containers.image was changed to viksil/pingpong:5.07
• environment variable PING_PORT with value "8080" was added.
• Unchanged Secret manifest from Exercise 4.01 was used.

apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: pingpong
spec:
  template:
    spec:
      containers:
      - image: viksil/pingpong:5.07
        imagePullPolicy: Always
        resources:
          limits:
            cpu: "30m"
            memory: "130Mi"
        ports:
        - containerPort: 8080
        env:
          - name: DB_URL
            valueFrom:
              secretKeyRef:
                name: pingpong-secret
                key: DB_URL
          - name: PING_PORT
            value: "8080"
        readinessProbe:
          initialDelaySeconds: 180 
          periodSeconds: 10
          httpGet:
              path: /healthz
              port: 8080

Log output

• Service and Deployment manifest were merged into a Knative Service manifest.
• spec.template.spec.containers.image was changed to viksil/log_output:5.07.
• environment variable LOG_PORT with value "8080" was added.

apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: log-output
spec:
  template:
    spec:
      containers:
      - image: viksil/log_output:5.07
        imagePullPolicy: Always
        resources:
          limits:
            cpu: "30m"
            memory: "130Mi"
        env:
          - name: LOG_PORT
            value: "8080"
        ports:
        - containerPort: 8080

Log reader

ConfigMap

apiVersion: v1
kind: ConfigMap
metadata:
  name: log-output-cfgmap
data:
  message: "hello world"
  information.txt: |
    this text is from file
  pingpong_hostname: "pingpong.default.172.27.0.2.sslip.io"
  log_hostname: "log-output.default.172.27.0.2.sslip.io"

Service

• Service and Deployment manifest were merged into a Knative Service manifest.
• spec.template.spec.containers.image was changed to viksil/log_output_reader:5.07.
• environment variable READ_PORT with value "8080" was added.

apiVersion: serving.knative.dev/v1
kind: Service
metadata:
  name: log-reader
spec:
  template:
    spec:
      volumes:
        - name: configmap-volume
          configMap:
            name: log-output-cfgmap
            items:
            - key: "information.txt"
              path: "information.txt" 
      containers:
      - image: viksil/log_output_reader:5.07
        imagePullPolicy: Always
        ports:
        - containerPort: 8080
        env:
        - name: MESSAGE
          valueFrom:
            configMapKeyRef:
              name: log-output-cfgmap
              key: message
        - name: PINGPONG_HOST
          valueFrom:
            configMapKeyRef:
              name: log-output-cfgmap
              key: pingpong_hostname
        - name: LOG_HOST
          valueFrom:
            configMapKeyRef:
              name: log-output-cfgmap
              key: log_hostname
        - name: READ_PORT
          value: "8080"
        volumeMounts:
        - name: configmap-volume
          mountPath: /usr/local/config
          readOnly: true
        readinessProbe:
          initialDelaySeconds: 270
          periodSeconds: 10
          httpGet:
              path: /healthz
              port: 8080

Commands

Frontend