Helm Schema Validator

A VS Code extension that validates your Helm values.yaml files against the JSON schema from a selected Helm chart. Shows inline diagnostics (squiggles) and errors in the Problems panel with accurate line/column ranges.

Features

• Select repository, chart, and version via Quick Pick / Command Palette
• Validate YAML files against values.schema.json from the chart (or override schema)
• Inline diagnostics with correct line/column positions
• Status bar shows current selection and validation status
• Helm CLI integration (optional) for repo/chart discovery
• Index.yaml fallback when Helm CLI is unavailable
• Configurable cache for index and chart downloads

Usage

1. Configure repositories

Option A – Import from Helm (recommended if Helm is installed)

1. Run helm repo add for your desired repositories
2. Run Helm Schema Validator: Import Repos from Helm from the Command Palette (Ctrl+Shift+P / Cmd+Shift+P)
3. Repositories are added to helmSchemaValidator.repositories

Option B – Manual configuration

Add to your settings (settings.json):

{
  "helmSchemaValidator.repositories": [
    { "name": "bitnami", "url": "https://charts.bitnami.com/bitnami" },
    { "name": "ingress-nginx", "url": "https://kubernetes.github.io/ingress-nginx" }
  ]
}

2. Select chart and version

1. Open a YAML file (e.g. values.yaml)
2. Click the Helm status bar item (bottom-left) or run Helm Schema Validator: Show Selectors
3. Choose Select Repository → Select Chart → Select Version
4. The extension fetches the chart, extracts values.schema.json, and validates

3. Validate

Validation runs automatically:

• When you open a YAML file
• On document changes (debounced)
• When you change the selected repository/chart/version
• When you run Helm Schema Validator: Validate Current File

4. Override schema (optional)

To use a custom schema instead of the chart’s:

{
  "helmSchemaValidator.schemaPath": "/path/to/values.schema.json"
}

Or use a URL:

{
  "helmSchemaValidator.schemaPath": "https://example.com/values.schema.json"
}

Commands

Configuration

Schema sources

The extension resolves the schema in this order:

1. Override – If helmSchemaValidator.schemaPath is set, use that
2. Chart schema – If the chart contains values.schema.json, use it
3. No schema – Show: "No values.schema.json found in chart; cannot validate."

The extension does not generate schemas; the chart must include values.schema.json or you must provide an override.

Screenshots

• Screenshot: Status bar showing Helm selection
• Screenshot: Quick Pick for repository selection
• Screenshot: Inline diagnostics in values.yaml

Troubleshooting

"No Helm repositories found"

• Run Helm Schema Validator: Import Repos from Helm (if Helm is installed)
• Or add repositories in helmSchemaValidator.repositories

"No values.schema.json found in chart"

• The chart does not include values.schema.json
• Provide helmSchemaValidator.schemaPath to use a custom schema
• Some charts do not ship a schema; use a community schema if available

"Repository URL not found"

• Ensure the selected repository exists in helmSchemaValidator.repositories
• If using Helm CLI, run helm repo update

"Chart download failed"

• Check network connectivity
• Verify the chart version exists in the repository
• Run Helm Schema Validator: Clear Cache and try again

Helm CLI not found

• The extension falls back to fetching index.yaml from the repo URL
• Ensure repositories are configured in settings
• Install Helm and add it to PATH for better discovery

Diagnostics at wrong position

• If exact node location is not found, diagnostics fall back to the document start
• The extension uses the YAML AST for precise mapping; report issues if mapping is wrong

License

Copyright © 2026 Rohit Phatak. All rights reserved. This software is proprietary. Unauthorized copying, modification, distribution, or use is prohibited without explicit permission from the author.