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Helm Charts

All applications use Helm for templating Kubernetes manifests. A shared library chart (portfolio-common) provides base templates, while each application has a thin wrapper chart.

Chart Structure​

devops-portfolio-manager/
├── portfolio-common/          # Library chart (shared templates)
│   ├── Chart.yaml
│   └── templates/
│       ├── _deployment.tpl
│       ├── _service.tpl
│       ├── _ingress.tpl
│       ├── _hpa.tpl
│       └── _servicemonitor.tpl
├── bookmarked/
│   ├── Chart.yaml             # depends on portfolio-common
│   ├── values.yaml            # app-specific config
│   └── templates/
│       ├── deployment.yaml    # one-liner include
│       └── service.yaml       # one-liner include
├── educationelly/
│   └── ...
└── ... (one directory per app)

Library Chart Pattern​

Application templates are one-liners that delegate to the library chart:

# bookmarked/templates/deployment.yaml
{{- include "portfolio-common.deployment" (dict "component" "client" "context" $) }}

The library chart template reads values from the app's values.yaml and generates a complete Deployment manifest with standardized labels, resource limits, health checks, and image pull configuration.

Values Structure​

Each app's values.yaml follows a consistent structure:

replicaCount: 1

client:
  image:
    repository: maxjeffwell/bookmarked-client
    tag: "20250205-143022-a1b2c3d"
  port: 80

server:
  image:
    repository: maxjeffwell/bookmarked-server
    tag: "20250205-143022-a1b2c3d"
  port: 8080

autoscaling:
  enabled: true
  minReplicas: 1
  maxReplicas: 3
  targetCPUUtilizationPercentage: 70

ingress:
  host: bookmarked.el-jefe.me

Init Containers​

The library chart conditionally renders init containers when defined in an app's values.yaml:

# In portfolio-common/_deployment.tpl
{{- if $.Values.initContainers }}
initContainers:
  {{- toYaml $.Values.initContainers | nindent 8 }}
{{- end }}

This is used by apps that depend on external services being available at startup. For example, the AI gateway and GraphQL gateway use an init container to wait for Kafka:

# gateway/values.yaml
initContainers:
  - name: wait-for-kafka
    image: busybox:1.37
    command: ['sh', '-c', 'until nc -z kafka-bootstrap.microservices.svc 9092; do sleep 5; done']

The init container blocks pod startup until the dependency is reachable, preventing race conditions where the application tries to connect before the dependency is ready.

Dependency Resolution​

Each app chart declares portfolio-common as a file dependency:

# bookmarked/Chart.yaml
dependencies:
  - name: portfolio-common
    version: "0.1.0"
    repository: "file://../portfolio-common"

This means helm dependency update resolves the library chart from the local filesystem — no chart registry needed.