Deploying and monitoring with the Open Liberty application stack

This sample repository contains a custom Dockerfile and app-deploy.yaml which can be used to build and deploy an Open Liberty stack application and connect it to Prometheus for monitoring.

quick-start-security

The default quick-start-security configuration is removed and replaced with a configuration that has environment variables for the username and password.

<quickStartSecurity userName="${stack.username}" userPassword="${stack.password}" />

Secret Injection

To set the username and password environment variables, the app is injecting values from a pre-defined Secret called "mySecret". This must exist in the cluster namespace before deploying.

env:
  - name: STACK_USERNAME
  valueFrom:
    secretKeyRef:
      key: username
      name: mySecret
  - name: STACK_PASSWORD
  valueFrom:
    secretKeyRef:
      key: password
      name: mySecret

Service Monitor

To allow for easy detection from Prometheus, this app defines a Service Monitor that will use the credentials from "mySecret" to connect to the deployment's /metrics endpoint.

monitoring:
  endpoints:
  - basicAuth:
      password:
        key: password
        name: mysecret
      username:
        key: username
        name: mysecret
    interval: 5s
    tlsConfig:
      insecureSkipVerify: true
  labels:
    monitoring: ''

Prometheus will need to be configured with the correct serviceMonitorNamespaceSelector to scrape the namespace where this app is deployed and also with the correct serviceMonitorSelector to scrape service monitors with the label "monitoring."