lnbits/misc-aio/NOSTR_INTEGRATION.md

Nostr Integration for LNBits Users

This document describes the changes made to integrate Nostr keypairs with LNBits user accounts.

Overview

The integration adds Nostr keypair generation to user accounts, allowing each user to have a unique Nostr identity. The private key is stored securely in the database, while the public key is derived and made available through the API.

Changes Made

1. Database Migration

File: lnbits/core/migrations.py

• Added m034_add_nostr_private_key_to_accounts() migration
• Adds prvkey column to the accounts table for Nostr private keys

2. Model Updates

File: lnbits/core/models/users.py

• Added prvkey field to Account model for Nostr private key
• The existing pubkey field is now used to store the Nostr public key

3. CRUD Operations

File: lnbits/core/crud/users.py

• Updated get_user_from_account() to use the existing pubkey field (now contains Nostr public key)
• Updated get_accounts() SQL query to include prvkey field

4. API Endpoints

File: lnbits/core/views/user_api.py

• Modified user creation to automatically generate Nostr keypair and set the pubkey field
• Added new endpoint /users/api/v1/nostr/pubkeys to get all user public keys
• Endpoint requires admin privileges and returns:

  [
    {
      "user_id": "user_id",
      "username": "username", 
      "nostr_public_key": "public_key_hex"
    }
  ]
  

5. Command Line Interface

File: lnbits/commands.py

• Updated create_user command to generate Nostr keypair
• Displays the generated public key when creating users via CLI

API Usage

Creating a User (Automatically generates Nostr keypair)

POST /users/api/v1/user
Content-Type: application/json

{
  "username": "testuser",
  "email": "test@example.com",
  "password": "password123",
  "password_repeat": "password123"
}

Getting All User Public Keys

GET /users/api/v1/nostr/pubkeys
Authorization: Bearer <admin_token>

Response:
[
  {
    "user_id": "abc123",
    "username": "user1",
    "pubkey": "02a1b2c3d4e5f6..."
  },
  {
    "user_id": "def456", 
    "username": "user2",
    "pubkey": "03b2c3d4e5f6a1..."
  }
]

Getting Individual User (includes Nostr public key)

GET /users/api/v1/user/{user_id}

Response:
{
  "id": "abc123",
  "username": "user1",
  "email": "user1@example.com",
  "pubkey": "02a1b2c3d4e5f6...",  # This is the Nostr public key
  "created_at": "2024-01-01T00:00:00Z",
  "updated_at": "2024-01-01T00:00:00Z",
  ...
}

Security Considerations

1. Private Key Storage: Nostr private keys are stored in the prvkey field but are never exposed through the API
2. Public Key Storage: Nostr public keys are stored directly in the pubkey field for efficiency
3. Admin Access: The public key listing endpoint requires admin privileges
4. Consistent Naming: pubkey and prvkey provide clear, consistent field names

Migration

To apply the database changes:

1. Run the migration: python -m lnbits db migrate
2. The migration will add the prvkey column to existing accounts for Nostr private keys
3. New users will automatically get Nostr keypairs generated

Testing

Use the provided test script to verify the integration:

python test_nostr_integration.py

Dependencies

The integration uses the existing lnbits.utils.nostr module which provides:

• generate_keypair(): Generates new Nostr keypairs
• PrivateKey class: For key manipulation and public key derivation

Future Enhancements

Potential improvements could include:

1. NIP-19 encoding support (npub/nsec format)
2. Nostr event signing capabilities
3. Integration with Nostr relays for user discovery
4. User profile metadata storage