rlsp-yaml
YAML language support powered by rlsp-yaml — fast, schema-aware, built in Rust.
Features
Core editing:
- Hover information (schema-aware descriptions and formatted examples)
- Completion (structural + schema-driven with snippet support)
- Document symbols (outline view)
- Folding ranges
- Selection ranges (AST-based expand/shrink)
- On-type formatting (auto-indent after colons and block scalars)
- Rename symbol (anchors/aliases)
- Go-to-definition and find references (anchors/aliases)
- Document links (URL detection +
!include file paths)
- Code actions (flow/block conversion, tab fix, unused anchor delete, quoted bool, block scalar)
- Code lens (schema title/URL at top of document)
- Semantic highlighting (keys, values, anchors, aliases, tags, comments)
- Full-document and range formatting
- Color picker integration for CSS color values
Validation:
- YAML syntax errors
- Duplicate key detection
- Unused anchor warnings
- Flow style warnings
- Key ordering enforcement (opt-in)
- Custom tag validation
- JSON Schema validation (required properties, type checking, enum constraints)
Schema support:
- SchemaStore.org integration (auto-detects schemas by filename)
- Kubernetes schema auto-detection
- Schema association via modeline (
# yaml-language-server: $schema=<url>)
- Schema association via workspace settings (glob-based mapping)
- HTTP schema fetching with caching
Installation
Install from the VS Code Marketplace.
The extension bundles a prebuilt rlsp-yaml binary — no separate installation required.
Build from source:
git clone https://github.com/chdalski/rlsp
cd rlsp/rlsp-yaml/integrations/vscode
pnpm install
pnpm run build
Then run pnpm run package to produce a .vsix file and install it with Extensions: Install from VSIX in VS Code.
Configuration
Key settings (configured under rlsp-yaml.* in VS Code settings):
| Setting |
Default |
Description |
schemaStore |
true |
Enable SchemaStore.org integration |
schemas |
{} |
Map schema URLs to glob patterns |
kubernetesVersion |
"master" |
Kubernetes schema version |
keyOrdering |
false |
Enforce alphabetical key ordering |
formatPrintWidth |
80 |
Line width for formatting |
formatSingleQuote |
false |
Use single quotes in formatted output |
customTags |
[] |
Custom YAML tags to recognize |
httpProxy |
"" |
HTTP proxy URL for schema fetching |
See docs/configuration.md for the full settings reference — modelines, validators, formatting, and schema fetching.
Commands
All commands are available via the Command Palette (Ctrl+Shift+P / Cmd+Shift+P):
| Command |
Description |
rlsp-yaml: Restart Server |
Restart the language server |
rlsp-yaml: Show Output |
Open the server output channel |
rlsp-yaml: Show Version |
Display the running server version |
