helm/values at 48395b06a54cff32ba69a2c8ddb2672a824d145e - helm

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Álvaro Torres Cogollo 8ffdc81970 feat: New --values-tpl flag with limited template support Use --values-tpl to dynamically generate values based on previously merged configuration. Templates have access to .Values with basic template functions. This is especially useful when you don't have control over upstream chart templates and want to avoid forking just to add tpl support. Templates are rendered after all other value sources (--values, --set) and have access to the merged .Values context: ```bash helm install myapp ./chart --values-tpl dynamic.yaml.tpl helm install myapp ./chart \ --values base.yaml \ --set environment=production \ --values-tpl computed.yaml.tpl ``` ```yaml region: us-east-1 environment: dev replicas: {{ if eq .Values.environment "production" }}5{{ else }}1{{ end }} resourceTier: {{ .Values.environment \| upper }} endpoint: "https://{{ .Values.region }}.example.com" ``` 1. Chart defaults (`values.yaml`) 2. All `--values` files 3. All `--set` flags 4. All `--values-tpl` files (rendered with access to steps 1-3) Problem:* Each cluster is in a different AWS region/account, and you need different ECR registries. You want to: - Avoid committing per-cluster files (values-prod-us.yaml, values-prod-eu.yaml, etc.) - Not edit upstream chart templates to add tpl support - Keep ArgoCD unaware of chart-specific paths (image.registry, etc.) Solution: Single template file in git, cluster-specific values via ArgoCD: ```yaml image: registry: "{{ .Values.accountId }}.dkr.ecr.{{ .Values.region }}.amazonaws.com" repository: myapp tag: "1.0.0" service: extraEnvironment: # Arbitrary path in values CLUSTER_NAME: "{{ .Values.clusterName }}" ``` ```yaml spec: helm: parameters: - name: clusterName value: prod-us-east - name: region value: us-east-1 - name: accountId value: "123456789" valueTplFiles: - values-custom.yaml.tpl ``` ```yaml spec: helm: parameters: - name: clusterName value: prod-eu-west - name: region value: eu-west-1 - name: accountId value: "987654321" valueTplFiles: - values-custom.yaml.tpl ``` - Access to `.Values` from previous merge steps - Sprig functions: `default`, `upper`, `lower`, `trim`, etc. - Format functions: `toYaml`, `toJson`, `toToml`, `fromYaml`, `fromJson`, `fromToml` - Conditionals: `if`/`else`, `range` - Remote templates: `http://`, `https://`, etc. - `include` (requires chart template context) - `tpl` (requires chart template context) - `lookup` (requires Kubernetes client) Signed-off-by: Álvaro Torres Cogollo <atorrescogollo@gmail.com>	2 weeks ago
..
options.go	feat: New --values-tpl flag with limited template support	2 weeks ago
options_test.go	feat: New --values-tpl flag with limited template support	2 weeks ago

Álvaro Torres Cogollo 8ffdc81970 feat: New --values-tpl flag with limited template support

Use --values-tpl to dynamically generate values based on previously
merged configuration. Templates have access to .Values with basic
template functions.

This is especially useful when you don't have control over upstream
chart templates and want to avoid forking just to add tpl support.

Templates are rendered after all other value sources (--values, --set)
and have access to the merged .Values context:

```bash
helm install myapp ./chart --values-tpl dynamic.yaml.tpl

helm install myapp ./chart \
  --values base.yaml \
  --set environment=production \
  --values-tpl computed.yaml.tpl
```

```yaml
region: us-east-1
environment: dev

replicas: {{ if eq .Values.environment "production" }}5{{ else }}1{{ end }}
resourceTier: {{ .Values.environment | upper }}
endpoint: "https://{{ .Values.region }}.example.com"
```

1. Chart defaults (`values.yaml`)
2. All `--values` files
3. All `--set*` flags
4. All `--values-tpl` files (rendered with access to steps 1-3)

**Problem:** Each cluster is in a different AWS region/account, and you need
different ECR registries. You want to:
- Avoid committing per-cluster files (values-prod-us.yaml, values-prod-eu.yaml, etc.)
- Not edit upstream chart templates to add tpl support
- Keep ArgoCD unaware of chart-specific paths (image.registry, etc.)

**Solution:** Single template file in git, cluster-specific values via ArgoCD:

```yaml
image:
  registry: "{{ .Values.accountId }}.dkr.ecr.{{ .Values.region }}.amazonaws.com"
  repository: myapp
  tag: "1.0.0"

service:
  extraEnvironment:  # Arbitrary path in values
    CLUSTER_NAME: "{{ .Values.clusterName }}"
```

```yaml
spec:
  helm:
    parameters:
    - name: clusterName
      value: prod-us-east
    - name: region
      value: us-east-1
    - name: accountId
      value: "123456789"
    valueTplFiles:
    - values-custom.yaml.tpl
```

```yaml
spec:
  helm:
    parameters:
    - name: clusterName
      value: prod-eu-west
    - name: region
      value: eu-west-1
    - name: accountId
      value: "987654321"
    valueTplFiles:
    - values-custom.yaml.tpl
```

- Access to `.Values` from previous merge steps
- Sprig functions: `default`, `upper`, `lower`, `trim`, etc.
- Format functions: `toYaml`, `toJson`, `toToml`, `fromYaml`, `fromJson`, `fromToml`
- Conditionals: `if`/`else`, `range`
- Remote templates: `http://`, `https://`, etc.

- `include` (requires chart template context)
- `tpl` (requires chart template context)
- `lookup` (requires Kubernetes client)

Signed-off-by: Álvaro Torres Cogollo <atorrescogollo@gmail.com>

options.go

feat: New --values-tpl flag with limited template support

options_test.go

feat: New --values-tpl flag with limited template support