Slackin - Modernized 🚀

A modernized version of the public Slack invite system, updated for 2025 with the latest dependencies and Node.js features.

✨ What's New

This is a completely modernized version of the original slackin project with:

🔧 Technology Updates

• Express 5.1.0 (latest) - from Express 4.15.4
• Socket.io 4.8.1 (latest) - from Socket.io 2.0.3
• Node.js 18+ support - from Node.js 6.11.1
• ES Modules - converted from CommonJS
• Modern HTTP client - replaced superagent with undici
• Zero vulnerabilities - all dependencies updated and secure

🏗️ Architecture Improvements

• Removed Babel transpilation (native ES modules)
• Removed Gulp build system (no longer needed)
• Updated to modern async/await patterns
• Improved error handling and logging
• Built-in body parsing (Express 5.x)
• Graceful shutdown handling

🛡️ Security Enhancements

• Latest Express with security improvements
• Updated reCAPTCHA integration
• Modern IP address handling
• Secure dependency versions

📋 Requirements

• Node.js 18.0.0 or higher
• Slack API token with admin privileges
• Google reCAPTCHA site key and secret

📖 Need help getting tokens? See SETUP.md for detailed step-by-step instructions.

🆓 Free Plan Compatibility

✅ Slackin works on Slack FREE plans!

• Works with free Slack workspaces (with limitations)
• You must be a workspace admin to generate API tokens
• User count updates will be slower due to 2025 API rate limits
• Uses 1 of your 10 allowed app installations

📋 Full details: See Free Plan Summary in SETUP.md

🚀 Quick Start

Installation

# Clone the repository
git clone https://github.com/Aswintechie/slack-join.git
cd slack-join
# Install dependencies
npm install
# Set up environment variables
cp env.example .env
# Edit .env with your Slack and reCAPTCHA credentials# See SETUP.md for detailed instructions on getting tokens# Start the server
npm start

Environment Variables

Option 1: Using .env file (Recommended)

Copy the example environment file and edit it with your values:

cp env.example .env
# Edit .env with your actual values

Option 2: Export manually

Set these environment variables or pass them as command line arguments:

export SLACK_SUBDOMAIN=your-team-name
export SLACK_API_TOKEN=xoxp-your-token
export GOOGLE_CAPTCHA_SECRET=your-secret
export GOOGLE_CAPTCHA_SITEKEY=your-sitekey

🔑 Quick Token Reference

Token	Where to Get It	Example
SLACK_SUBDOMAIN	Your Slack URL: https://TEAM.slack.com	mycompany
SLACK_API_TOKEN	Slack API	xoxp-123...
GOOGLE_CAPTCHA_SECRET	reCAPTCHA Admin	6LcYYY...
GOOGLE_CAPTCHA_SITEKEY	reCAPTCHA Admin	6LcXXX...

📋 Detailed instructions: See SETUP.md for complete step-by-step guides.

Command Line Usage

# Basic usage
node bin/slackin.js team-name api-token captcha-secret captcha-sitekey
# With options
node bin/slackin.js \
--port 3000 \
--hostname 0.0.0.0 \
--channels "general,random" \
--cors \
team-name api-token captcha-secret captcha-sitekey

Development Mode

# Auto-restart on changes (Node 18+ built-in)
npm run dev

⚙️ Configuration Options

Option	Environment Variable	Description	Default
--port	PORT	Port to listen on	3000
--hostname	HOSTNAME	Hostname to bind to	0.0.0.0
--channels	SLACK_CHANNELS	Comma-separated channel list	All channels
--interval	SLACK_INTERVAL	Polling interval (ms)	5000
--cors	-	Enable CORS	false
--silent	-	Disable logging	false
--coc	-	Code of Conduct URL	none
--css	-	Custom CSS URL	none

🏃‍♂️ Running in Production

Using PM2

npm install -g pm2
# Create ecosystem file
cat > ecosystem.config.js << 'EOF'module.exports = { apps: [{ name: 'slackin', script: 'bin/slackin.js', env: { NODE_ENV: 'production', PORT: 3000, SLACK_SUBDOMAIN: 'your-team', SLACK_API_TOKEN: 'xoxp-your-token', GOOGLE_CAPTCHA_SECRET: 'your-secret', GOOGLE_CAPTCHA_SITEKEY: 'your-sitekey' } }]}EOF# Start with PM2
pm2 start ecosystem.config.js

Using Docker

FROM node:18-alpine
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production
COPY . .
USER node
EXPOSE 3000
CMD ["node", "bin/slackin.js"]

Using systemd

[Unit]Description=Slackin Slack Invite System
After=network.target
[Service]Type=simple
User=node
WorkingDirectory=/opt/slackin
ExecStart=/usr/bin/node bin/slackin.js
Restart=always
RestartSec=10
Environment=NODE_ENV=production
Environment=PORT=3000
Environment=SLACK_SUBDOMAIN=your-team
Environment=SLACK_API_TOKEN=xoxp-your-token
Environment=GOOGLE_CAPTCHA_SECRET=your-secret
Environment=GOOGLE_CAPTCHA_SITEKEY=your-sitekey
[Install]WantedBy=multi-user.target

🔧 API Endpoints

• GET / - Slack invite page
• POST /invite - Submit invite request
• GET /iframe - Embeddable iframe
• GET /iframe/dialog - Iframe dialog version
• GET /badge.svg - SVG status badge
• GET /data - JSON status data

🌐 Integration

Embed as iframe

<iframesrc="https://your-domain.com/iframe" width="174" height="30"
frameborder="0"></iframe>

Status Badge

![Slack](https://your-domain.com/badge.svg)

🛠️ Development

Project Structure

slack-join/
├── bin/
│ └── slackin.js # CLI entry point
├── lib/
│ ├── index.js # Main server logic
│ ├── slack.js # Slack API integration
│ ├── slack-invite.js # Invite functionality
│ ├── vd-wrapper.js # Virtual DOM wrapper
│ ├── splash.js # Main page template
│ ├── iframe.js # Iframe template
│ ├── badge.js # SVG badge generator
│ ├── log.js # Logging utilities
│ └── assets/ # Static assets
├── package.json # Dependencies and scripts
└── README.md # This file

Key Dependencies

• express ^5.1.0 - Web framework
• socket.io ^4.8.1 - Real-time communication
• undici ^7.11.0 - Modern HTTP client
• virtual-dom ^2.1.1 - Virtual DOM for templates
• email-regex ^1.0.0 - Email validation
• cors ^2.8.5 - CORS handling

🔄 Migration from Original Slackin

If you're migrating from the original slackin:

1. Node.js: Update to Node.js 18+
2. Dependencies: Run npm install (all updated automatically)
3. Environment: Same environment variables work
4. API: All endpoints remain compatible
5. Build: No build step required (removed Babel/Gulp)

🚨 Breaking Changes from Original

• Node.js 18+ required (was 6.11.1)
• ES Modules (may affect custom integrations)
• Updated Slack API usage (ensure your token has correct scopes)
• Modern reCAPTCHA (v2 - ensure your keys are compatible)

📝 Environment Variables Reference

# Required
SLACK_SUBDOMAIN=your-slack-team # Your Slack workspace name
SLACK_API_TOKEN=xoxp-... # Slack API token (admin required)
GOOGLE_CAPTCHA_SECRET=... # reCAPTCHA secret key 
GOOGLE_CAPTCHA_SITEKEY=... # reCAPTCHA site key# Optional
PORT=3000 # Server port
HOSTNAME=0.0.0.0 # Bind hostname
SLACK_CHANNELS=general,random # Allowed channels
SLACK_INTERVAL=5000 # Polling interval (ms)
EMAIL_SLACK_LIST=user@domain.com # Restricted email list

🤝 Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Test with npm test
5. Submit a pull request

📄 License

MIT License - see LICENSE file for details

🙏 Acknowledgments

• Original slackin by @rauchg
• Modernization updates for 2025 compatibility
• Express.js, Socket.io, and Node.js communities

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Ready to invite the world to your Slack? 🌍✨