/chart-java

Helm chart for Java microservices

Primary LanguageMakefileMIT LicenseMIT

chart-java

Build Status

This chart is intended for simple Java microservices.

We will take small PRs and small features to this chart but more complicated needs should be handled in your own chart.

NOTE: /health/readiness and /health/liveness exposed by spring boot 2.3.0 actuator are used for readiness and liveness checks.

This chart adds below templates from chart-library based on the chosen configuration:

Example configuration

applicationPort: 8080
environment:
  REFORM_TEAM: cnp
  REFORM_SERVICE_NAME: rhubarb-backend
  REFORM_ENVIRONMENT: preview
  ROOT_APPENDER: CNP
  CONFIG_TEMPLATE: "{{ .Release.Name }}-config"
configmap:
  VAR_A: VALUE_A
  VAR_B: VALUE_B
secrets: 
  ENVIRONMENT_VAR:
      secretRef: some-secret-reference
      key: connectionString
  ENVIRONMENT_VAR_OTHER:
      secretRef: some-secret-reference-other
      key: connectionStringOther
      disabled: true #ENVIRONMENT_VAR_OTHER will not be set to environment
keyVaults:
  "cmc":
    secrets:
      - smoke-test-citizen-username
      - smoke-test-user-password
  "s2s":
    secrets:
      - microservicekey-cmcLegalFrontend
applicationInsightsInstrumentKey: "some-key"

If you wish to use pod identity for accessing the key vaults instead of a service principal you need to set a flag aadIdentityName: <identity-name> e.g.

aadIdentityName: cmc
keyVaults:
  "cmc":
    usePodIdentity: true
    secrets:
      - smoke-test-citizen-username
      - smoke-test-user-password

Startup probes

Startup probes are defined in the library template and should be configured for slow starting applications. The default values below (defined in the chart) should be sufficient for most applications but can be overriden as required.

startupPath: '/health/liveness'
startupDelay: 5
startupTimeout: 3
startupPeriod: 10
startupFailureThreshold: 3

To configure startup probes for a slow starting application:

  • Set the value of (startupFailureThreshold x startupPeriodSeconds) to cover the longest startup time required by the application
  • If livenessDelay is currently configured, set the value to 0

Example configuration

The below example will allow the application 360 seconds to complete startup.

java:
  livenessDelay: 0
  startupPeriod: 120
  startupFailureThreshold: 3

Also see example pull request.

HPA Horizontal Pod Autoscaler

To adjust the number of pods in a deployment depending on CPU utilization AKS supports horizontal pod autoscaling. To enable horizontal pod autoscaling you can set the autoscaling section.

autoscaling:        # Default is true
  enabled: true 
  maxReplicas: 5    # Optional setting, will use the value of replicas + 2 if not set
  minReplicas: 2    # Optional setting, will use the value of replicas if not set
  targetCPUUtilizationPercentage: 80 # Default is 80% target CPU utilization

Postgresql

If you need to use a Postgresql database for testing then you can enable it by setting the following flag in your application config with:

java:
  environment:
    DB_HOST: "{{ .Release.Name }}-postgresql"
    DB_USER_NAME: "{{ .Values.postgresql.auth.username}}"
    DB_PASSWORD: "{{ .Values.postgresql.auth.password}}"

postgresql:
  #Whether to deploy the Postgres Chart or not
  enabled: true

Smoke and functional tests

From version 2.15.0 of this chart you can configure your functional and smoke tests to run just after deployment or at scheduled times as cron jobs.

java:
  testsConfig:
    keyVaults:
      cmc:
        excludeEnvironmentSuffix: false
        secretRef: "kvcreds"
        secrets:
          smoke-test-citizen-username: SMOKE_TEST_CITIZEN_USER
          smoke-test-user-password: SMOKE_TEST_CITIZEN_PASS
    environment:
      TEST_URL: http://plum-recipe-backend-java
      SLACK_CHANNEL: "platops-build-notices"
      SLACK_NOTIFY_SUCCESS: "true"
      CLUSTER_NAME: "aat-01-aks"

  smoketests:
    image: hmctspublic.azurecr.io/spring-boot/template-test
    enabled: true
    environment:
      TEST_URL: http://plum-recipe-backend-java-overridden

  functionaltests:
    image: hmctspublic.azurecr.io/spring-boot/template-test
    enabled: true

  smoketestscron:
    image: hmctspublic.azurecr.io/spring-boot/template-test
    enabled: true
    environment:
      TEST_URL: http://plum-recipe-backend-java-overridden2

  functionaltestscron:
    image: hmctspublic.azurecr.io/spring-boot/template-test
    enabled: true
    environment:
      TEST_URL: http://plum-recipe-backend-java-overridden2
      SOME_ENV: some-val

Development and Testing

Default configuration (e.g. default image and ingress host) is setup for preview. This is suitable for local development and testing.

  • Ensure you have logged in with az cli and are using preview subscription (use az account show to display the current one).
  • For local development see the Makefile for available targets.
  • To execute an end-to-end build, deploy and test run make.
  • to clean up deployed releases, charts, test pods and local charts, run make clean

helm test will deploy a busybox container alongside the release which performs a simple HTTP request against the service health endpoint. If it doesn't return HTTP 200 the test will fail. NOTE: it does NOT run with --cleanup so the test pod will be available for inspection.

Azure DevOps Builds

Builds are run against the 'nonprod' AKS cluster.

Pull Request Validation

A build is triggered when pull requests are created. This build will run helm lint, deploy the chart using ci-values.yaml and run helm test.

Release Build

Triggered when the repository is tagged (e.g. when a release is created). Also performs linting and testing, and will publish the chart to ACR on success.