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Event Coordination

Event coordination allows you to send real-time messages between external systems and active browser instances. This is particularly useful for multi-factor authentication (MFA) where you need to inject authentication codes during browser automation.

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Overview

The system provides two operations:
  • Signal Event: Send data to an event channel
  • Wait for Event: Listen for data on an event channel with timeout
Events are user-scoped and work across multiple browser instances.

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MFA Use Case

Handle MFA codes during automated login flows: 
// In your browser automation script
async function handleMFAFlow() {
  await page.fill('#username', 'user@example.com');
  await page.fill('#password', 'password');
  await page.click('#login-button');
  
  // Wait for MFA code from external system
  const mfaEvent = await waitForEvent('mfa_code', 30000);
  
  if (mfaEvent?.data?.code) {
    await page.fill('#mfa-code', mfaEvent.data.code);
    await page.click('#verify-button');
  }
}

// In your external system (mobile app, webhook, etc.)
async function sendMFACode(code) {
  await signalEvent('mfa_code', { code });
}

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Implementation

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Helper Functions

import AnchorBrowser from 'anchorbrowser';

const anchor_client = new AnchorBrowser({apiKey: process.env.ANCHOR_API_KEY});

async function signalEvent(eventName, data) {
  try {
    const response = await anchor_client.events.signal(eventName, { data: data || {} });
    return response;
  } catch (error) {
    throw new Error(`Failed to signal event: ${error.message}`);
  }
}

async function waitForEvent(eventName, timeoutMs = 60000) {
  try {
    const response = await anchor_client.events.waitFor(eventName, { timeoutMs });
    return response;
  } catch (error) {
    if (error.message.includes("408")) return null; // Timeout
    throw new Error(`Failed to wait for event: ${error.message}`);
  }
}

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Event Flow Patterns

Signal First, Wait Later (immediate consumption): 
await signalEvent("data", { value: "preloaded" });
const data = await waitForEvent("data", 1000); // Short timeout
Wait First, Signal Later (typical MFA flow): 
const waitPromise = waitForEvent("mfa_code", 60000);
// ... other operations ...
const mfaData = await waitPromise;

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Best Practices

  • Use descriptive event names: mfa_code_login, mfa_code_transfer
  • Always set appropriate timeouts
  • Validate received event data
  • Handle timeout scenarios gracefully