n8n-nodes-fast2sms

A feature-rich n8n community node for the Fast2SMS platform — India's popular bulk SMS, OTP and DLT messaging API.

Send SMS, verify OTPs, manage DLT templates, track deliveries, and automate webhook-driven workflows — all from within n8n.

✨ Features at a Glance

| Category | Operations | Highlights | |----------|-----------|------------| | 📱 SMS | Send, Send Bulk, Send & Wait for Delivery | DLT, DLT Manual & Quick routes | | 🔐 OTP | Send, Verify, Resend | Configurable expiry & length | | 📋 DLT Manager | Get Templates, Get Senders, Get Entities | Cached lookups, guided variable UI | | 📝 DLT Registry | Add Entity, Add Sender, Add Template | Bulk upload via Excel URLs | | 📊 Reports | Delivery Report, SMS Logs, Summary | Paginated, date-filtered | | 💰 Account | Get Wallet Balance | Real-time balance & SMS count | | 🔔 Webhooks | Create, Update, Delete, Get, Set Status | SMS & OTP services | | ⚡ Trigger | Delivery Webhook Trigger | Real-time delivery callbacks |

🚀 Installation

Via n8n Community Nodes UI (Recommended)

1. Go to Settings → Community Nodes
2. Click Install a community node
3. Enter: n8n-nodes-fast2sms
4. Click Install

Via npm

cd ~/.n8n
npm install n8n-nodes-fast2sms

Via Docker

Add to your Dockerfile:

RUN cd /home/node/.n8n && npm install n8n-nodes-fast2sms

⚙️ Setup

1. Get your API Key from Fast2SMS Dashboard → Dev API
2. In n8n, go to Credentials → New Credential → Fast2SMS API
3. Paste your API key — that's it!

The credential test automatically verifies your key against the /dev/wallet endpoint.

📱 SMS Operations

Three Routes Supported

| Route | Best For | Sender ID | DLT Template | Price | |-------|---------|-----------|--------------|-------| | DLT | Production bulk SMS | Required | From DLT Manager | Account-specific | | DLT Manual | Custom template text | Required | User-provided | Account-specific | | Quick | Testing & dev | Auto (FSTSMS) | Not needed | ₹5.00/SMS |

Send SMS

Send to one or multiple recipients with automatic number validation, batching, and cost estimation.

• ✅ Smart batching — automatically splits large recipient lists into API-sized batches (100/batch)
• ✅ Number normalization — accepts +91, 0, or raw 10-digit formats
• ✅ Duplicate detection — removes duplicate numbers before sending
• ✅ Segment estimation — calculates SMS segments and estimated cost before sending
• ✅ GSM-7 / UCS-2 detection — correctly counts extension characters (€, [, ], etc.) that cost 2 septets

Send & Wait for Delivery

Sends the SMS and holds the workflow until the delivery report resolves — no polling node needed.

• Two-stage architecture: inline polling (≤60s) and putExecutionToWait (up to 1 hour)
• Configurable resolve conditions: all delivered, any terminal, or any failure
• Graceful timeout handling with partial results

Personalised / Per-Recipient Messages

Turn on "Personalise per Recipient" to send a unique message to each input item via the /dev/custom endpoint. Each row gets its own text, variables, and recipient — validated up-front before anything is sent.

🔐 OTP Operations

| Operation | Description | |-----------|-------------| | Send | Dispatch an OTP via a pre-configured OTP template | | Verify | Check if the user-submitted OTP is correct | | Resend | Re-send the last OTP to the same number |

• Configurable OTP length (4–10 digits) and expiry (1–10,080 minutes)
• Numeric-only variable validation enforced locally before the API call

📋 DLT Manager (Read Operations)

Browse your approved DLT assets without leaving n8n:

• Get Templates — list all templates, optionally filtered by Sender ID
• Get Sender IDs — list approved sender IDs with entity names
• Get Entities — de-duplicated entity list derived from senders
• Get Template by ID — look up a single template with its variable slots

All lookups are cached (5-minute TTL) so opening dropdowns doesn't burn API calls.

📝 DLT Registry (Write Operations)

Register new DLT assets programmatically:

| Operation | What It Does | |-----------|-------------| | Add Entity | Register a new entity with screenshot proof | | Add Sender | Register a sender ID under an entity | | Add Sender (Excel) | Bulk-register senders via an Excel URL | | Add Template | Register a message template with screenshots | | Add Template (Excel) | Bulk-register templates via an Excel URL |

All URLs are validated to be publicly reachable http(s):// links.

📊 Reports & Logs

| Operation | Description | |-----------|-------------| | Get Delivery Report | Per-recipient delivery status for a request ID | | Get SMS Logs | Paginated logs with date range filtering | | Get Summary | Aggregate delivery stats for a date range |

Delivery reports can be returned as one item per recipient (split mode) or as a single summary object.

🔔 Webhook Management

Full CRUD for Fast2SMS delivery webhooks:

• Create — register a callback URL with event filters
• Get / Get Many — list registered webhooks
• Update — modify URL, events, headers, or payload format
• Delete — remove a webhook
• Set Status — activate / deactivate without deleting

Supports both SMS and OTP webhook services.

⚡ Trigger Node

The Fast2SMS Trigger node receives real-time delivery callbacks:

• Automatic mode — creates/deletes the webhook for you when the workflow activates
• Manual mode — bring your own webhook ID
• HMAC verification — optional shared-secret authentication with timing-safe comparison
• Payload normalization — snake_case API fields mapped to camelCase with ISO timestamps

🎯 Variable System

The DLT route uses positional {#var#} template variables. This node makes them safe and easy:

| Mode | Description | |------|-------------| | Guided | One labeled input box per variable, auto-named from template context | | Pipe-delimited | Classic value1|value2|value3 format | | List | JSON array of values |

Built-in validation catches:

• Wrong variable count
• Pipe characters inside values (escaping or stripping)
• Control characters that break SMS encoding
• Empty variables
• Template rendering verification (round-trip check)

🔒 Security

This package follows security best practices:

• 🔐 API keys — never logged, never in URLs; header-only authentication
• 🛡️ Timing-safe comparison — webhook HMAC verification uses SHA-256 + timingSafeEqual
• 🚫 Path traversal prevention — webhook IDs validated against strict [A-Za-z0-9_-]+ pattern
• 🔑 Cache isolation — template cache keyed by SHA-256 hash of API key (cross-tenant safe)
• 📝 Header redaction — sensitive headers stripped from webhook payloads
• ⚠️ GET method warning — opt-in only, with clear data exposure warnings

📋 Compatibility

| Requirement | Version | |-------------|---------| | n8n | ≥ 1.69.0 | | Node.js | ≥ 20.15 | | Runtime dependencies | Zero — only n8n-workflow as peer |

🧪 Testing

# Run the full test suite
npm test

# Watch mode
npm run test:watch

# Coverage report
npm run test:coverage

154 tests covering phone normalization, variable validation, segment counting, datetime parsing, webhook path security, and more.

📦 Development

# Clone the repo
git clone https://github.com/AakashRawat04/n8n-nodes-fast2sms.git
cd n8n-nodes-fast2sms

# Install dependencies
npm install

# Build
npm run build

# Lint
npm run lint

# Link to your local n8n for testing
npm link
cd ~/.n8n
npm link n8n-nodes-fast2sms

📄 License

MIT — use it however you like.

🤝 Contributing

Contributions are welcome! Please:

1. Fork the repo
2. Create a feature branch (git checkout -b feat/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feat/amazing-feature)
5. Open a Pull Request

📚 Resources

• Fast2SMS Documentation
• Fast2SMS Dashboard
• n8n Community Nodes Documentation
• npm Package