HumanBehavior SDK automatically identifies and tracks users across sessions using persistent user IDs and properties.

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Automatic User Identification

The SDK handles user identification using cookies. A unique user ID is generated and stored in a cookie on first visit, and persists for 1 year. Initializing the SDK handles user authentication automatically.

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User Identification Methods

Use this method when you have access to a tracker instance. This is the most common approach. 
// After successful login/signup, identify the user with their current session
const endUserId = await tracker.identifyUser({
  userProperties: {
    email: user.email,
    name: user.name,
    plan: user.plan
  }
});

console.log('User identified with ID:', endUserId);
Returns: Promise<string> - The endUserId of the identified user

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2. identifyUserGlobally() - Global Function

Use this function when you don’t have direct access to a tracker instance, or for global user identification. 
import { identifyUserGlobally } from 'humanbehavior-js';

// Identify user globally (works from anywhere in your app)
const endUserId = await identifyUserGlobally({
  email: user.email,
  name: user.name,
  userId: user.id,
  plan: user.plan
});

console.log('User identified globally with ID:', endUserId);
Returns: Promise<string> | null - The endUserId if successful, null if tracker not found

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Framework-Specific Examples

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NextAuth.js Example

// In your NextAuth configuration
import { HumanBehaviorTracker } from 'humanbehavior-js';

export default NextAuth({
  events: {
    async signIn({ user, account }) {
      // Initialize HumanBehavior tracker
      const tracker = HumanBehaviorTracker.init(process.env.NEXT_PUBLIC_HUMAN_BEHAVIOR_API_KEY);
      
      // Identify user with current endUserId
      const endUserId = await tracker.identifyUser({
        userProperties: {
          email: user.email,
          name: user.name,
          userId: user.id,
          provider: account?.provider
        }
      });
      
      console.log('User identified:', endUserId);
    }
  }
});

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Firebase Auth Example

// In your Firebase auth state listener
import { HumanBehaviorTracker } from 'humanbehavior-js';

onAuthStateChanged(auth, async (user) => {
  if (user) {
    // Initialize HumanBehavior tracker
    const tracker = HumanBehaviorTracker.init(process.env.NEXT_PUBLIC_HUMAN_BEHAVIOR_API_KEY);
    
    // Identify user with current endUserId
    const endUserId = await tracker.identifyUser({
      userProperties: {
        email: user.email,
        name: user.displayName,
        image: user.photoURL,
        userId: user.uid,
        provider: user.providerData[0]?.providerId
      }
    });
    
    console.log('User identified:', endUserId);
  }
});

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Google Auth Example

// In your Google Auth sign-in handler
import { HumanBehaviorTracker } from 'humanbehavior-js';

const handleGoogleSignIn = async () => {
  try {
    // Your Google Auth logic here
    const user = await signInWithGoogle();
    
    if (user) {
      // Initialize HumanBehavior tracker
      const tracker = HumanBehaviorTracker.init(process.env.NEXT_PUBLIC_HUMAN_BEHAVIOR_API_KEY);
      
      // Identify user with current endUserId
      const endUserId = await tracker.identifyUser({
        userProperties: {
          email: user.email,
          name: user.displayName,
          image: user.photoURL,
          userId: user.uid,
          provider: 'google'
        }
      });
      
      console.log('User identified:', endUserId);
    }
  } catch (error) {
    console.error('Google sign-in failed:', error);
  }
};

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Client-side Identification

You can also identify users client-side after successful authentication or for client-only applications:
Placement: Call identifyUser after successful login or signup, not during page initialization.
// After successful login/signup, identify the user with their current session
const endUserId = await tracker.identifyUser({
  userProperties: {
    email: user.email,
    name: user.name,
    plan: user.plan
  }
});

console.log('User identified with ID:', endUserId);

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User Logout

When a user logs out, you should clear any user-specific data. The SDK doesn’t have a built-in logout method, so handle this in your authentication logic: 
// Handle user logout
const handleLogout = () => {
  // Your logout logic here
  // Clear user data, redirect, etc.
  
  // Note: The SDK automatically maintains the session ID
  // You don't need to call any specific logout method
};

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Complete Example

AuthComponents.jsx
import { HumanBehaviorTracker } from 'humanbehavior-js';

function LoginForm() {
    const handleLogin = async (formData) => {   
      // ... Your authentication logic here ...

      // Upon successful authentication, identify user in the current session
      if (loginSuccessful) {
        const tracker = HumanBehaviorTracker.init(process.env.NEXT_PUBLIC_HUMAN_BEHAVIOR_API_KEY);
        
        const endUserId = await tracker.identifyUser({
          userProperties: {
            email: user.email,
            name: user.name,
            plan: 'premium'
          }
        });
        
        console.log('User successfully identified:', endUserId);
      }
    }
    
    return (
        <form onSubmit={handleLogin}>
            {/* Your form fields */}
        </form>
    );
}

function LogOutButton() {
  const handleLogout = () => {
    // ... Your logout logic here ...
    // Clear user data, redirect, etc.
  }

  return (
    <button onClick={handleLogout}>Log Out</button>
  );
}

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Privacy & Segmentation

  • User properties are available in your analytics dashboard for segmentation and filtering
  • You can update user info at any time (e.g., after signup, plan change)
  • The SDK supports privacy regulations and pseudonymous IDs

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Properties & Options

Property/OptionTypeDescription
endUserIdstringUnique user ID (auto-generated and stored in a cookie by default).
identifyUser()functionIdentify user with properties (returns Promise<string>).
identifyUserGlobally()functionGlobal user identification function (returns Promise).
userPropertiesobjectAny key-value pairs (e.g., email, name, plan, etc.).
cookiestringStores user ID for 365 days.
identifyUser({ userProperties }) fields:
FieldTypeDescription
AnyanyYou can provide any user property fields.
Example:
emailstringUser’s email address.
namestringUser’s name.
userIdstringYour internal user ID.
planstringUser’s plan or segment.

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Method Comparison

MethodWhen to UseReturnsNotes
tracker.identifyUser()You have tracker instancePromise<string>Most common, direct access
identifyUserGlobally()No tracker access, global usagePromise<string or null>Works from anywhere, requires global tracker