Bumi Accessibility LSP Server

A Language Server Protocol (LSP) server for accessibility linting that can be used with any LSP-compatible editor, including JetBrains IDEs (IntelliJ IDEA, WebStorm, PHPStorm, etc.).

Developer: Flat Electronics Canada Limited
License: MIT
GitHub: https://github.com/bumi-ca/accessibility-scanner-core

Features

- 19 accessibility rules covering WCAG 2.0, 2.1, and 2.2
- Support for HTML, JSX/TSX, Vue, Angular, and Razor files
- Real-time diagnostics as you type
- Quick fixes for common accessibility issues
- ARIA completions for roles and attributes
- Configurable WCAG conformance level (A, AA, AAA)

Installation

$3

``bash
npm install -g @flatelectronics/accessibility-lsp-server
`

$3

`bash
cd lsp-server
npm install
npm run build
`

Usage

$3

The server communicates via stdin/stdout:

`bash
bumi-lsp


or


node dist/server.js
`

$3

JetBrains IDEs require the LSP4IJ plugin to connect to LSP servers.

#### Step 1: Install LSP4IJ Plugin

1. Open your JetBrains IDE (IntelliJ IDEA, WebStorm, etc.)
2. Go to Settings/Preferences > Plugins
3. Click Marketplace tab
4. Search for "LSP4IJ"
5. Click Install and restart the IDE

#### Step 2: Configure Bumi LSP Server

1. Go to Settings/Preferences > Languages & Frameworks > Language Servers
2. Click the + button to add a new server
3. Configure the server:

- Name: Bumi Accessibility
- Command: bumi-lsp (if installed globally) or the full path to node /path/to/lsp-server/dist/server.js
- File patterns: .html;.htm;.jsx;.tsx;.vue;.cshtml;*.razor

4. Click OK to save

#### Step 3: Verify Installation

1. Open an HTML or JSX file
2. Add an tag without an alt attribute
3. You should see a diagnostic warning from Bumi

$3

Using nvim-lspconfig:

`lua
local lspconfig = require('lspconfig')
local configs = require('lspconfig.configs')

if not configs.bumi then
configs.bumi = {
default_config = {
cmd = { 'bumi-lsp' },
filetypes = { 'html', 'javascriptreact', 'typescriptreact', 'vue' },
root_dir = lspconfig.util.root_pattern('package.json', '.git'),
settings = {
bumi = {
enabled = true,
wcag = {
version = '2.2',
level = 'AA'
}
}
}
}
}
end

lspconfig.bumi.setup{}
`

$3

Using LSP package:

`json
{
"clients": {
"bumi": {
"command": ["bumi-lsp"],
"enabled": true,
"selector": "source.html, source.jsx, source.tsx, text.html.vue",
"settings": {
"bumi": {
"enabled": true,
"wcag": {
"version": "2.2",
"level": "AA"
}
}
}
}
}
}
`

$3

Using lsp-mode:

`elisp
(require 'lsp-mode)

(lsp-register-client
(make-lsp-client
:new-connection (lsp-stdio-connection '("bumi-lsp"))
:activation-fn (lsp-activate-on "html" "javascriptreact" "typescriptreact" "vue")
:server-id 'bumi))

(add-hook 'html-mode-hook #'lsp)
(add-hook 'web-mode-hook #'lsp)
`

Configuration

The server accepts configuration via the bumi namespace:

`json
{
"bumi": {
"enabled": true,
"wcag": {
"version": "2.2",
"level": "AA"
},
"rules": {
"disabled": []
}
}
}
`

$3

| Setting | Type | Default | Description |
|---------|------|---------|-------------|
| bumi.enabled | boolean | true | Enable/disable the linter |
| bumi.wcag.version | string | "2.2" | WCAG version: "2.0", "2.1", or "2.2" |
| bumi.wcag.level | string | "AA" | Conformance level: "A", "AA", or "AAA" |
| bumi.rules.disabled | array | [] | List of rule IDs to disable |

Rules

The server includes 19 accessibility rules:

| Rule ID | WCAG | Level | Version | Description |
|---------|------|-------|---------|-------------|
| IMG_MISSING_ALT | 1.1.1 | A | 2.0 | Image missing alt attribute |
| IMG_SUSPICIOUS_ALT | 1.1.1 | A | 2.0 | Suspicious alt text patterns |
| BUTTON_NO_NAME | 4.1.2 | A | 2.0 | Button without accessible name |
| LINK_EMPTY | 2.4.4 | A | 2.0 | Empty link element |
| LINK_GENERIC_TEXT | 2.4.4 | A | 2.0 | Generic link text |
| INPUT_MISSING_LABEL | 1.3.1, 3.3.2 | A | 2.0 | Form input missing label |
| HEADING_EMPTY | 1.3.1, 2.4.6 | A | 2.0 | Empty heading element |
| HEADING_SKIP_LEVEL | 1.3.1 | A | 2.0 | Skipped heading level |
| HTML_MISSING_LANG | 3.1.1 | A | 2.0 | Missing lang attribute |
| ARIA_INVALID_ROLE | 4.1.2 | A | 2.0 | Invalid ARIA role |
| ARIA_HIDDEN_FOCUSABLE | 4.1.2 | A | 2.0 | Focusable element with aria-hidden |
| TABINDEX_POSITIVE | 2.4.3 | A | 2.0 | Positive tabindex value |
| AUTOCOMPLETE_MISSING | 1.3.5 | AA | 2.1 | Missing autocomplete attribute |
| FORM_NO_SUBMIT | 2.1.1 | A | 2.0 | Form without submit button |
| TABLE_MISSING_HEADERS | 1.3.1 | A | 2.0 | Table missing headers |
| IFRAME_MISSING_TITLE | 2.4.1, 4.1.2 | A | 2.0 | Iframe missing title |
| VIDEO_MISSING_CAPTIONS | 1.2.2 | A | 2.0 | Video without captions track |
| AUDIO_MISSING_CONTROLS | 1.4.2 | A | 2.0 | Audio without controls |
| TARGET_SIZE_MINIMUM | 2.5.8 | AA | 2.2 | Target size may be too small |

Quick Fixes

The server provides automatic quick fixes for:

- Adding alt="" to images
- Adding aria-label to empty buttons
- Changing positive tabindex to tabindex="0"
- Adding title to iframes
- Adding controls to audio elements

Completions

The server provides completions for:

- ARIA roles (role="button", role="navigation", etc.)
- ARIA attributes (aria-label, aria-labelledby, etc.)
- Common accessibility attributes (alt, tabindex, etc.)

Troubleshooting

$3

1. Ensure Node.js 18+ is installed
2. Check the server path is correct
3. Verify the server is executable: chmod +x dist/server.js`

$3

1. Check the file type is supported
2. Verify LSP4IJ plugin is installed (JetBrains)
3. Check server logs for errors

$3

1. Ensure LSP4IJ plugin is updated to latest version
2. Restart the IDE after configuration changes
3. Check Help > Show Log in Finder/Explorer for errors

Contributing

Contributions are welcome! Please see our GitHub repository for guidelines.

License

MIT License - Copyright (c) 2026 Flat Electronics Canada Limited