Helm Values Generation Skill

Generate Helm values files that only override necessary defaults.

Core Principles

•Minimal diff: Output ONLY values that differ from chart defaults
•Proper types: Booleans as booleans, not strings
•Constraint validation: Verify values against chart's allowed options
•CLI args for metadata: name/namespace are CLI args, not values
•Verification-first: Read chart defaults before generating

Process

Step 1: Analyze Chart

Before generating values, understand the chart:

bash

# Get chart info
helm show values <chart> [--version <version>]

# Or for OCI charts
helm show values oci://registry/chart

# Check chart README for constraints
helm show readme <chart>

Gather:

code

[ ] Default values identified
[ ] Required values (no defaults) identified
[ ] Value constraints documented (enums, ranges)
[ ] Chart version pinned

Step 2: Generate Values

Structure:

yaml

# values.yaml
# Only override what differs from defaults

# Example: Overriding replica count (default: 1)
replicaCount: 3

# Example: Overriding image (default: nginx:latest)
image:
  repository: myregistry/myapp
  tag: "1.2.3"  # Quotes for version strings

# Example: Boolean (NOT "true" string)
autoscaling:
  enabled: true

What to EXCLUDE:

•Values matching chart defaults
•name: or namespace: (use helm install <name> -n <ns>)
•Commented-out defaults
•Redundant nested keys

Step 3: Type Handling

YAML Type	Example	Common Mistake
Boolean	`enabled: true`	`enabled: "true"`
Integer	`replicas: 3`	`replicas: "3"`
String version	`tag: "1.2.3"`	`tag: 1.2.3` (parsed as float)
Null	`value: null`	`value: ""`
List	`- item`	Forgetting `-`

Step 4: Validation

bash

# Lint values
helm lint <chart> -f values.yaml

# Template to verify
helm template <release> <chart> -f values.yaml

# Dry-run install
helm install <release> <chart> -f values.yaml --dry-run

Common Chart Patterns

Ingress:

yaml

ingress:
  enabled: true
  className: nginx
  hosts:
    - host: app.example.com
      paths:
        - path: /
          pathType: Prefix
  tls:
    - secretName: app-tls
      hosts:
        - app.example.com

Resources:

yaml

resources:
  requests:
    cpu: 100m
    memory: 128Mi
  limits:
    cpu: 500m
    memory: 512Mi

Service Account (with IRSA/Workload Identity):

yaml

serviceAccount:
  create: true
  annotations:
    eks.amazonaws.com/role-arn: arn:aws:iam::ACCOUNT:role/ROLE

Anti-patterns to Avoid

•Including name: or namespace: in values
•Copying all defaults with minor changes
•String booleans: "true" instead of true
•Unquoted version strings that look like numbers
•Hardcoded secrets (use external-secrets, sealed-secrets, etc.)
•Values that don't exist in the chart schema

Output Format

When generating values, output:

•Chart analysis: What chart, version, key constraints
•Values file: Only overridden values with comments
•Install command: Full helm install/upgrade command
•Validation command: How to verify before applying
•Notes: Any external dependencies (secrets, CRDs, etc.)

Example Workflow

User: "Generate Helm values for nginx-ingress"

Response:

yaml

# values.yaml for ingress-nginx
# Chart: ingress-nginx/ingress-nginx v4.10.0
# Only non-default values shown

controller:
  replicaCount: 2

  resources:
    requests:
      cpu: 100m
      memory: 90Mi
    limits:
      cpu: 500m
      memory: 256Mi

  service:
    type: LoadBalancer

bash

# Install command
helm install ingress-nginx ingress-nginx/ingress-nginx \
  --namespace ingress-nginx \
  --create-namespace \
  -f values.yaml

# Verify
helm template ingress-nginx ingress-nginx/ingress-nginx -f values.yaml | kubectl apply --dry-run=client -f -