Authentication - Agentic Avatars SDK

Authentication

Learn how to authenticate API requests using API keys and JWT tokens.

Two Authentication Methods

The Control API uses two different authentication methods:

1. Kaltura Session (KS) (for session creation)

2. JWT Token (for session control)

Kaltura Session (KS) Authentication

Used for: Creating new sessions

Header: Authorization: KS <ks>

Example:

curl -X POST https://api.avatar.us.kaltura.ai/v1/avatar-session/create \
  -H "Authorization: KS your-kaltura-session-here" \
  -H "Content-Type: application/json" \
  -d '{"visualConfig": {"id": "visual-123"}}'

Getting Your Kaltura Session

You can generate a Kaltura Session (KS) using the Kaltura API. See the Kaltura Session Creation Guide for detailed instructions.

Alternatively, contact your Kaltura representative for assistance.

Storing Your Kaltura Session

Security

NEVER expose your Kaltura Session in:

Client-side code
Frontend applications
Public repositories
Browser DevTools

ALWAYS store it:

In environment variables
In secure secret managers
On your backend server only

Good practices:

# .env file
AVATAR_KS=your-kaltura-session-here

// Node.js
const KS = process.env.AVATAR_KS;

# Python
import os
KS = os.environ.get('AVATAR_KS')

JWT Token Authentication

Used for: All session operations (except creation)

Header: Authorization: Bearer {token}

Example:

curl -X POST https://api.avatar.us.kaltura.ai/v1/avatar-session/:sessionId/say-text \
  -H "Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9..." \
  -H "Content-Type: application/json" \
  -d '{"text": "Hello!"}'

How to Get a Token

The JWT token is returned when you create a session:

const response = await fetch('https://api.avatar.us.kaltura.ai/v1/avatar-session/create', {
  method: 'POST',
  headers: {
    Authorization: `KS ${process.env.AVATAR_KS}`,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    visualConfig: { id: 'visual-123' },
  }),
});

const data = await response.json();
console.log('Token:', data.token); // JWT token here
console.log('Session ID:', data.sessionId);

Token Properties

Scope: Valid only for the specific session
Expiration: Tied to session lifetime
Permissions: Full control over the session
Single use: One token per session

Using the Token

// After creating session
const { sessionId, token } = await createSession();

// Use token for all operations
await fetch(`https://api.avatar.us.kaltura.ai/v1/avatar-session/${sessionId}/say-text`, {
  method: 'POST',
  headers: {
    Authorization: `Bearer ${token}`,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({ text: 'Hello!' }),
});

Authentication Flow

┌──────────────┐
│   Backend    │
│              │
│ 1. Store     │
│    KS        │
└──────┬───────┘
       │
       │ Create session with KS
       ▼
┌──────────────┐
│ Avatar API   │
│              │
│ 2. Validate  │
│    KS        │
│              │
│ 3. Generate  │
│    JWT token │
└──────┬───────┘
       │
       │ Return sessionId + token
       ▼
┌──────────────┐
│   Backend    │
│              │
│ 4. Send to   │
│    frontend  │
└──────┬───────┘
       │
       │ sessionId + token
       ▼
┌──────────────┐
│   Frontend   │
│              │
│ 5. Use token │
│    for       │
│    display   │
└──────────────┘

Complete Example

Backend Server

import express from 'express';
import fetch from 'node-fetch';

const app = express();
app.use(express.json());

// Kaltura Session stored securely
const AVATAR_KS = process.env.AVATAR_KS;
const AVATAR_BASE_URL = 'https://api.avatar.us.kaltura.ai/v1/avatar-session';

// Session storage (in-memory for demo, use database in production)
const sessions = new Map();

// Create session endpoint
app.post('/api/avatar/create-session', async (req, res) => {
  try {
    // Call Kaltura API with KS
    const response = await fetch(`$\{AVATAR_BASE_URL\}/create`, {
      method: 'POST',
      headers: {
        Authorization: `KS $\{AVATAR_KS\}`, // Secure on server
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        visualConfig: { id: req.body.visualId },
        voiceConfig: req.body.voiceId ? { id: req.body.voiceId } : undefined,
      }),
    });

    if (!response.ok) {
      throw new Error(`API error: ${response.status}`);
    }

    const data = await response.json();

    // Store session info
    sessions.set(data.sessionId, {
      token: data.token,
      createdAt: new Date(),
    });

    // Return to frontend (token is safe to send)
    res.json({
      sessionId: data.sessionId,
      token: data.token,
    });
  } catch (error) {
    console.error('Failed to create session:', error);
    res.status(500).json({ error: 'Failed to create session' });
  }
});

// Control endpoint (uses token)
app.post('/api/avatar/say-text', async (req, res) => {
  try {
    const { sessionId, token, text } = req.body;

    // Verify session exists
    if (!sessions.has(sessionId)) {
      return res.status(404).json({ error: 'Session not found' });
    }

    // Call Kaltura API with token
    const response = await fetch(`$\{AVATAR_BASE_URL\}/${sessionId}/say-text`, {
      method: 'POST',
      headers: {
        Authorization: `Bearer ${token}`,
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({ text }),
    });

    if (!response.ok) {
      throw new Error(`API error: ${response.status}`);
    }

    const data = await response.json();
    res.json(data);
  } catch (error) {
    console.error('Failed to say text:', error);
    res.status(500).json({ error: 'Failed to say text' });
  }
});

Frontend Client

// Create session (token from backend)
const { sessionId, token } = await fetch('/api/avatar/create-session', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    visualId: 'visual-123',
    voiceId: 'voice-456',
  }),
}).then((r) => r.json());

console.log('Session ID:', sessionId);
console.log('Token:', token);

// Use token for display
import { KalturaAvatarSession } from '@unisphere/models-sdk-js';

const session = new KalturaAvatarSession(token, {
  baseUrl: 'https://api.avatar.us.kaltura.ai/',
});
session.attachAvatar('avatar-container');

// Control from backend
await fetch('/api/avatar/say-text', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
    sessionId,
    token,
    text: 'Hello from the backend!',
  }),
});

Error Responses

401 Unauthorized

Kaltura Session:

{
  "success": false,
  "error": "Invalid Kaltura Session"
}

Causes:

Kaltura Session is missing
Kaltura Session is invalid
Kaltura Session is expired

Solutions:

Verify Kaltura Session is correct
Check Authorization: KS <ks> header is set
Contact Kaltura for new session

Token:

{
  "success": false,
  "error": "Invalid or expired token"
}

Causes:

Token is missing
Token is invalid
Session has ended
Token has expired

Solutions:

Verify token is correct
Check Authorization: Bearer {token} header
Create a new session if needed

403 Forbidden

{
  "success": false,
  "error": "Insufficient permissions"
}

Causes:

Kaltura Session doesn't have required permissions
Token doesn't match session

Security Best Practices

1. Kaltura Session Security

DO:

Store in environment variables
Use secret managers (AWS Secrets Manager, Azure Key Vault)
Rotate sessions regularly
Limit session scope if possible

DON'T:

Commit to version control
Include in client code
Share via email or chat
Log in plain text

2. Token Security

DO:

Send tokens over HTTPS only
Store tokens temporarily
Clear tokens when session ends
Validate tokens server-side

DON'T:

Store tokens long-term
Share tokens between users
Log tokens in plain text

3. HTTPS Only

Always use HTTPS in production:

// Bad - HTTP
const baseUrl = 'http://api.avatar.example.com';

// Good - HTTPS
const baseUrl = 'https://api.avatar.example.com';

4. Request Validation

Validate all requests before calling the API:

app.post('/api/avatar/say-text', async (req, res) => {
  // Validate input
  if (!req.body.text || req.body.text.length > 1000) {
    return res.status(400).json({ error: 'Invalid text' });
  }

  // Validate session exists
  if (!sessions.has(req.body.sessionId)) {
    return res.status(404).json({ error: 'Session not found' });
  }

  // Call API
  // ...
});

Next Steps

Create Session - Create your first session
Say Text - Make the avatar speak
API Examples - Complete working examples

Authentication​

Two Authentication Methods​

1. Kaltura Session (KS) (for session creation)​

2. JWT Token (for session control)​

Kaltura Session (KS) Authentication​

Getting Your Kaltura Session​

Storing Your Kaltura Session​

JWT Token Authentication​

How to Get a Token​

Token Properties​

Using the Token​

Authentication Flow​

Complete Example​

Backend Server​

Frontend Client​

Error Responses​

401 Unauthorized​

403 Forbidden​

Security Best Practices​

1. Kaltura Session Security​

2. Token Security​

3. HTTPS Only​

4. Request Validation​

Next Steps​

Authentication

Two Authentication Methods

1. Kaltura Session (KS) (for session creation)

2. JWT Token (for session control)

Kaltura Session (KS) Authentication

Getting Your Kaltura Session

Storing Your Kaltura Session

JWT Token Authentication

How to Get a Token

Token Properties

Using the Token

Authentication Flow

Complete Example

Backend Server

Frontend Client

Error Responses

401 Unauthorized

403 Forbidden

Security Best Practices

1. Kaltura Session Security

2. Token Security

3. HTTPS Only

4. Request Validation

Next Steps