SDK Methods

Complete reference for all ExtensionLogin SDK methods.

Creating a Client

ExtensionLogin(apiKey, options?)

Create an ExtensionLogin client instance.

javascript

import ExtensionLogin from 'extensionlogin';

const extLogin = ExtensionLogin('el_live_xxxxxx');

// With options
const extLogin = ExtensionLogin('el_live_xxxxxx', {
  apiUrl: 'https://api.extensionlogin.com/v1',
  trialDays: 7
});

Parameters:

Parameter	Type	Default	Description
`apiKey`	`string`	Required	Your ExtensionLogin API key
`options.apiUrl`	`string`	Production URL	API endpoint (for self-hosted)
`options.trialDays`	`number`	`7`	Number of days for free trials

Returns: ExtensionLoginClient

Background Service

startBackground()

Initialize the SDK in a background service worker. Must be called once when the extension starts.

javascript

// background.js
import ExtensionLogin from 'extensionlogin';

const extLogin = ExtensionLogin('el_live_xxxxxx');
extLogin.startBackground();

Returns: Promise<void>

What it does:

Records installation date if not already set
Sets up storage change listeners for events
Sets up message handlers for cross-context communication

User Methods

getUser()

Get the current user's status.

javascript

const user = await extLogin.getUser();

Returns: Promise<ExtensionLoginUser | null>

typescript

interface ExtensionLoginUser {
  id: string;
  email: string;
  name: string | null;
  paid: boolean;
  paidAt: Date | null;
  subscriptionStatus: 'active' | 'past_due' | 'canceled' | 'none';
  subscriptionCancelAt: Date | null;
  plan: ExtensionLoginPlan | null;
  installedAt: Date;
  trialStartedAt: Date | null;
  trialActive: boolean;
  trialDaysRemaining: number;
}

Example:

javascript

const user = await extLogin.getUser();

if (user) {
  console.log(`Welcome, ${user.name || user.email}!`);
  console.log('Paid:', user.paid);
  console.log('Trial active:', user.trialActive);
} else {
  console.log('No user logged in');
}

isAuthenticated()

Check if a user is currently logged in.

javascript

const isLoggedIn = await extLogin.isAuthenticated();

Returns: Promise<boolean>

Example:

javascript

if (await extLogin.isAuthenticated()) {
  showDashboard();
} else {
  showLoginForm();
}

hasPaidAccess()

Check if user has paid access (either paid subscription or active trial).

javascript

const canAccessPremium = await extLogin.hasPaidAccess();

Returns: Promise<boolean>

Example:

javascript

if (await extLogin.hasPaidAccess()) {
  showPremiumFeatures();
} else {
  showUpgradePrompt();
}

identify(userData)

Identify a user and send their data to connected CRMs.

javascript

const result = await extLogin.identify({
  email: '[email protected]',
  name: 'John Doe',
  metadata: { plan: 'pro' }
});

Parameters:

Field	Type	Required	Description
`email`	`string`	Yes	User's email address
`name`	`string`	No	Full name
`metadata`	`object`	No	Custom key-value data

Returns: Promise<IdentifyResult>

typescript

interface IdentifyResult {
  success: boolean;
  error?: string;
}

Example:

javascript

const result = await extLogin.identify({
  email: '[email protected]',
  name: 'John Doe',
  metadata: {
    source: 'extension',
    version: '1.0.0'
  }
});

if (result.success) {
  console.log('User identified successfully');
} else {
  console.error('Error:', result.error);
}

javascript

const result = await extLogin.login('[email protected]', 'password123');

Parameters:

Field	Type	Description
`email`	`string`	User's email address
`password`	`string`	User's password

Returns: Promise<LoginResult>

typescript

interface LoginResult {
  success: boolean;
  user?: ExtensionLoginUser;
  error?: string;
}

Example:

javascript

const result = await extLogin.login(email, password);

if (result.success) {
  console.log('Logged in:', result.user.email);
} else {
  console.error('Login failed:', result.error);
}

register(email, password, name?)

javascript

const result = await extLogin.register('[email protected]', 'password123', 'John Doe');

Parameters:

Field	Type	Required	Description
`email`	`string`	Yes	User's email address
`password`	`string`	Yes	User's password
`name`	`string`	No	User's display name

Returns: Promise<RegisterResult>

typescript

interface RegisterResult {
  success: boolean;
  user?: ExtensionLoginUser;
  error?: string;
}

logout()

Log out the current user.

javascript

await extLogin.logout();

Returns: Promise<void>

Example:

javascript

document.getElementById('logout-btn').addEventListener('click', async () => {
  await extLogin.logout();
  showLoginForm();
});

validateToken()

Validate the current token with the server and refresh user data.

javascript

const isValid = await extLogin.validateToken();

Returns: Promise<boolean>

Example:

javascript

// Check if token is still valid on extension startup
const isValid = await extLogin.validateToken();
if (!isValid) {
  // Token expired or invalid, show login
  showLoginForm();
}

getToken()

Get the current authentication token.

javascript

const token = await extLogin.getToken();

Returns: Promise<string | null>

Trial Methods

startTrial()

Start a free trial for the current user.

javascript

const result = await extLogin.startTrial();

Returns: Promise<TrialResult>

typescript

interface TrialResult {
  success: boolean;
  user?: ExtensionLoginUser;
  error?: string;
}

Example:

javascript

const result = await extLogin.startTrial();

if (result.success) {
  console.log('Trial started!');
  console.log('Days remaining:', result.user.trialDaysRemaining);
} else {
  console.error('Error:', result.error);
}

Google OAuth Methods

initGoogleAuth(redirectUrl)

Initialize the Google OAuth flow. Returns an auth URL to open.

javascript

const result = await extLogin.initGoogleAuth('https://yourextension.com/callback');

Parameters:

Field	Type	Description
`redirectUrl`	`string`	URL to redirect after OAuth

Returns: Promise<InitGoogleAuthResult>

typescript

interface InitGoogleAuthResult {
  success: boolean;
  authUrl?: string;
  state?: string;
  error?: string;
}

completeGoogleAuth(code, state, redirectUrl)

Complete the Google OAuth flow by exchanging the authorization code.

javascript

const result = await extLogin.completeGoogleAuth(code, state, redirectUrl);

Parameters:

Field	Type	Description
`code`	`string`	Authorization code from Google
`state`	`string`	State parameter from initGoogleAuth
`redirectUrl`	`string`	Same redirect URL used in initGoogleAuth

Returns: Promise<LoginResult>

Payment Methods

Methods for handling subscriptions and payments with Stripe.

getPlans()

Get available subscription plans configured in the dashboard.

javascript

const result = await extLogin.getPlans();
if (result.success) {
  console.log('Available plans:', result.plans);
}

Returns: Promise<GetPlansResult>

typescript

interface GetPlansResult {
  success: boolean;
  plans?: ExtensionLoginPlan[];
  error?: string;
}

interface ExtensionLoginPlan {
  id: string;
  name: string;
  priceInCents: number;
  currency: string;
  interval: 'month' | 'year' | 'once';
  intervalCount: number;
  features?: string[];
  stripePriceId?: string;
}

openPaymentPage(planId, options?)

Create a Stripe checkout session and get the URL to open.

javascript

const result = await extLogin.openPaymentPage('plan_monthly', {
  successUrl: chrome.runtime.getURL('success.html'),
  cancelUrl: chrome.runtime.getURL('popup.html')
});

if (result.success) {
  // Open checkout in new tab
  chrome.tabs.create({ url: result.checkoutUrl });
}

Parameters:

Field	Type	Required	Description
`planId`	`string`	Yes	Plan ID from getPlans()
`options.successUrl`	`string`	No	Redirect URL after successful payment
`options.cancelUrl`	`string`	No	Redirect URL if user cancels

Returns: Promise<CheckoutResult>

typescript

interface CheckoutResult {
  success: boolean;
  checkoutUrl?: string;
  sessionId?: string;
  error?: string;
}

getSubscriptionStatus()

Get detailed subscription status for the current user.

javascript

const result = await extLogin.getSubscriptionStatus();

if (result.success) {
  const sub = result.subscription;
  console.log('Status:', sub.status);
  console.log('Plan:', sub.plan?.name);
  console.log('Renews:', sub.currentPeriodEnd);
}

Returns: Promise<SubscriptionResult>

typescript

interface SubscriptionResult {
  success: boolean;
  subscription?: SubscriptionDetails;
  error?: string;
}

interface SubscriptionDetails {
  active: boolean;
  status: 'active' | 'past_due' | 'canceled' | 'trialing' | 'none';
  plan: ExtensionLoginPlan | null;
  currentPeriodStart: Date | null;
  currentPeriodEnd: Date | null;
  cancelAt: Date | null;
  cancelAtPeriodEnd: boolean;
  trialEnd: Date | null;
}

openBillingPortal(returnUrl?)

Open the Stripe billing portal for subscription management.

javascript

const result = await extLogin.openBillingPortal(
  chrome.runtime.getURL('popup.html')
);

if (result.success) {
  chrome.tabs.create({ url: result.portalUrl });
}

Parameters:

Field	Type	Required	Description
`returnUrl`	`string`	No	URL to return to after portal

Returns: Promise<BillingPortalResult>

typescript

interface BillingPortalResult {
  success: boolean;
  portalUrl?: string;
  error?: string;
}

cancelSubscription()

Cancel the current subscription at the end of the billing period.

javascript

const result = await extLogin.cancelSubscription();

if (result.success) {
  console.log('Subscription will end on:', result.cancelAt);
}

Returns: Promise<CancelResult>

typescript

interface CancelResult {
  success: boolean;
  cancelAt?: Date;
  error?: string;
}

refreshSubscription()

Manually refresh subscription status and emit events if changed.

javascript

// Call after successful checkout to update local state
await extLogin.refreshSubscription();

Returns: Promise<void>

Events

The SDK provides event emitters for reacting to auth state changes.

onLogin

Fires when a user logs in.

javascript

extLogin.onLogin.addListener((user) => {
  console.log('User logged in:', user.email);
});

onLogout

Fires when a user logs out.

javascript

extLogin.onLogout.addListener(() => {
  console.log('User logged out');
});

onPaid

Fires when a user's paid status changes to true.

javascript

extLogin.onPaid.addListener((user) => {
  console.log('User paid:', user.email);
  unlockPremiumFeatures();
});

onTrialStarted

Fires when a user starts a trial.

javascript

extLogin.onTrialStarted.addListener((user) => {
  console.log('Trial started for:', user.email);
  console.log('Days remaining:', user.trialDaysRemaining);
});

onSubscriptionChange

Fires when subscription status changes (after payment, cancellation, etc.).

javascript

extLogin.onSubscriptionChange.addListener((subscription) => {
  console.log('Subscription status:', subscription.status);
  if (subscription.active) {
    unlockPremiumFeatures();
  } else {
    lockPremiumFeatures();
  }
});

Removing Listeners

javascript

const handler = (user) => console.log(user);

// Add listener
extLogin.onLogin.addListener(handler);

// Remove listener
extLogin.onLogin.removeListener(handler);

TypeScript Types

Full TypeScript definitions:

typescript

import ExtensionLogin from 'extensionlogin';
import type {
  ExtensionLoginUser,
  ExtensionLoginPlan
} from 'extensionlogin';

// Create client
const extLogin = ExtensionLogin('el_live_xxx');

// User type
interface ExtensionLoginUser {
  id: string;
  email: string;
  name: string | null;
  paid: boolean;
  paidAt: Date | null;
  subscriptionStatus: 'active' | 'past_due' | 'canceled' | 'none';
  subscriptionCancelAt: Date | null;
  plan: ExtensionLoginPlan | null;
  installedAt: Date;
  trialStartedAt: Date | null;
  trialActive: boolean;
  trialDaysRemaining: number;
}

// Plan type
interface ExtensionLoginPlan {
  id: string;
  name: string;
  priceInCents: number;
  currency: string;
  interval: 'month' | 'year' | 'once';
  intervalCount: number;
  features?: string[];
  stripePriceId?: string;
}

// Subscription details type
interface SubscriptionDetails {
  active: boolean;
  status: 'active' | 'past_due' | 'canceled' | 'trialing' | 'none';
  plan: ExtensionLoginPlan | null;
  currentPeriodStart: Date | null;
  currentPeriodEnd: Date | null;
  cancelAt: Date | null;
  cancelAtPeriodEnd: boolean;
  trialEnd: Date | null;
}

// Checkout options type
interface CheckoutOptions {
  successUrl?: string;
  cancelUrl?: string;
}

Usage Patterns

javascript

import ExtensionLogin from 'extensionlogin';

const extLogin = ExtensionLogin('el_live_xxx');

// Check user on popup open
async function init() {
  const user = await extLogin.getUser();
  if (user) {
    showDashboard(user);
  } else {
    showLogin();
  }
}

// Handle login
async function handleLogin(email, name) {
  const result = await extLogin.identify({ email, name });
  if (result.success) {
    const user = await extLogin.getUser();
    showDashboard(user);
  }
}

init();

Background Script Usage

javascript

import ExtensionLogin from 'extensionlogin';

const extLogin = ExtensionLogin('el_live_xxx');
extLogin.startBackground();

// Listen for auth events
extLogin.onLogin.addListener((user) => {
  // Notify other parts of extension
  chrome.runtime.sendMessage({ type: 'USER_LOGGED_IN', user });
});

extLogin.onLogout.addListener(() => {
  chrome.runtime.sendMessage({ type: 'USER_LOGGED_OUT' });
});

Checking Premium Access

javascript

async function checkAccess() {
  const user = await extLogin.getUser();

  if (!user) {
    return { access: false, reason: 'not_logged_in' };
  }

  if (user.paid) {
    return { access: true, reason: 'paid' };
  }

  if (user.trialActive) {
    return {
      access: true,
      reason: 'trial',
      daysRemaining: user.trialDaysRemaining
    };
  }

  return { access: false, reason: 'no_subscription' };
}

Payment Flow

javascript

import ExtensionLogin from 'extensionlogin';

const extLogin = ExtensionLogin('el_live_xxx');

// Display available plans
async function showPlans() {
  const result = await extLogin.getPlans();
  if (result.success) {
    result.plans.forEach(plan => {
      const price = (plan.priceInCents / 100).toFixed(2);
      console.log(`${plan.name}: $${price}/${plan.interval}`);
    });
  }
}

// Handle plan selection
async function selectPlan(planId) {
  const result = await extLogin.openPaymentPage(planId, {
    successUrl: chrome.runtime.getURL('success.html'),
    cancelUrl: chrome.runtime.getURL('popup.html')
  });

  if (result.success) {
    // Open Stripe checkout in new tab
    chrome.tabs.create({ url: result.checkoutUrl });
  }
}

// Listen for subscription changes
extLogin.onSubscriptionChange.addListener((subscription) => {
  if (subscription.active) {
    showPremiumFeatures();
  }
});

// On success page, refresh subscription status
async function handlePaymentSuccess() {
  await extLogin.refreshSubscription();
  const user = await extLogin.getUser();
  if (user?.paid) {
    showThankYouMessage();
  }
}

// Allow user to manage billing
async function openBilling() {
  const result = await extLogin.openBillingPortal(
    chrome.runtime.getURL('popup.html')
  );
  if (result.success) {
    chrome.tabs.create({ url: result.portalUrl });
  }
}

Next Steps

Examples - Real-world examples
Background Script - Service worker patterns
Google OAuth - Add Google sign-in

SDK Methods ​

Creating a Client ​

ExtensionLogin(apiKey, options?) ​

Background Service ​

startBackground() ​

User Methods ​

getUser() ​

isAuthenticated() ​

hasPaidAccess() ​

identify(userData) ​

login(email, password) ​

register(email, password, name?) ​

logout() ​

validateToken() ​

getToken() ​

Trial Methods ​

startTrial() ​

Google OAuth Methods ​

initGoogleAuth(redirectUrl) ​

completeGoogleAuth(code, state, redirectUrl) ​

Payment Methods ​

getPlans() ​

openPaymentPage(planId, options?) ​

getSubscriptionStatus() ​

openBillingPortal(returnUrl?) ​

cancelSubscription() ​

refreshSubscription() ​

Events ​

onLogin ​

onLogout ​

onPaid ​

onTrialStarted ​

onSubscriptionChange ​

Removing Listeners ​

TypeScript Types ​

Usage Patterns ​

Basic Popup Usage ​

Background Script Usage ​

Checking Premium Access ​

Payment Flow ​

Next Steps ​

SDK Methods

Creating a Client

ExtensionLogin(apiKey, options?)

Background Service

startBackground()

User Methods

getUser()

isAuthenticated()

hasPaidAccess()

identify(userData)

login(email, password)

register(email, password, name?)

logout()

validateToken()

getToken()

Trial Methods

startTrial()

Google OAuth Methods

initGoogleAuth(redirectUrl)

completeGoogleAuth(code, state, redirectUrl)

Payment Methods

getPlans()

openPaymentPage(planId, options?)

getSubscriptionStatus()

openBillingPortal(returnUrl?)

cancelSubscription()

refreshSubscription()

Events

onLogin

onLogout

onPaid

onTrialStarted

onSubscriptionChange

Removing Listeners

TypeScript Types

Usage Patterns

Basic Popup Usage

Background Script Usage

Checking Premium Access

Payment Flow

Next Steps