Best Practices

🏗️ Architecture Best Practices

1. Client Initialization

✅ Good: Singleton Pattern

// config/whatsapp.ts
let client: WhatsAppClient | null = null;

export function getWhatsAppClient(): WhatsAppClient {
  if (!client) {
    client = new WhatsAppClient({
      accessToken: process.env.WHATSAPP_ACCESS_TOKEN!,
      phoneNumberId: process.env.WHATSAPP_PHONE_NUMBER_ID!,
      timeout: 60000,
      webhookVerifyToken: process.env.WHATSAPP_WEBHOOK_TOKEN,
    });
  }
  return client;
}

❌ Avoid: Multiple Instances

// Don't create multiple instances
function sendMessage() {
  const client = new WhatsAppClient(config); // Creates new instance every time
  return client.sendText(to, message);
}

2. Environment Configuration

✅ Good: Environment-specific Configs

const config = {
  development: {
    accessToken: process.env.WHATSAPP_DEV_TOKEN!,
    phoneNumberId: process.env.WHATSAPP_DEV_PHONE_ID!,
    timeout: 10000,
  },
  production: {
    accessToken: process.env.WHATSAPP_PROD_TOKEN!,
    phoneNumberId: process.env.WHATSAPP_PROD_PHONE_ID!,
    timeout: 60000,
    businessId: process.env.WHATSAPP_BUSINESS_ID!,
  }
};

const environment = process.env.NODE_ENV as keyof typeof config;
const client = new WhatsAppClient(config[environment]);

📱 Message Best Practices

1. Message Content Guidelines

✅ Good: Clear and Concise

// Clear, actionable message
await client.sendText(to, 
  '📦 Your order #12345 has shipped!\n\n' +
  '🚚 Tracking: ABC123\n' +
  '📅 Expected: March 15\n\n' +
  'Track: https://track.example.com/ABC123'
);

❌ Avoid: Verbose Messages

// Too much information
await client.sendText(to,
  'We are pleased to inform you that your order number 12345 which was placed on March 10th, 2024...'
);

2. Message Formatting

✅ Good: Structured Content

const formatOrderUpdate = (order: Order) => [
  '📦 Order Update',
  '',
  `Order #: ${order.id}`,
  `Status: ${order.status}`,
  `Items: ${order.items.length}`,
  '',
  '📍 Shipping Address:',
  order.shippingAddress.split('\n').map(line => `  ${line}`).join('\n'),
  '',
  `💰 Total: $${order.total}`,
  '',
  'Questions? Reply to this message.'
].join('\n');

await client.sendText(to, formatOrderUpdate(order));

3. Interactive Message Design

✅ Good: Logical Button Groups

// Clear, related actions
await client.sendButtons(to, 'Order #12345 - What would you like to do?', [
  { id: 'track', title: '📦 Track' },
  { id: 'modify', title: '✏️ Modify' },
  { id: 'support', title: '💬 Help' }
], {
  header: { type: 'text', text: 'Order Management' },
  footer: 'Choose an action'
});

❌ Avoid: Unrelated Options

// Confusing, unrelated buttons
await client.sendButtons(to, 'Your order shipped', [
  { id: 'weather', title: 'Weather' },
  { id: 'news', title: 'News' },
  { id: 'games', title: 'Games' }
]);

⚡ Performance Optimization

1. Media Management

✅ Good: Upload Once, Reuse

class MediaManager {
  private mediaCache = new Map<string, string>();
  
  async getOrUploadMedia(filePath: string, type: MediaType): Promise<string> {
    const cacheKey = `${filePath}-${type}`;
    
    if (this.mediaCache.has(cacheKey)) {
      return this.mediaCache.get(cacheKey)!;
    }
    
    const buffer = fs.readFileSync(filePath);
    const response = await client.uploadMedia(buffer, type);
    
    this.mediaCache.set(cacheKey, response.id);
    return response.id;
  }
  
  async sendCachedImage(to: string, filePath: string, caption?: string) {
    const mediaId = await this.getOrUploadMedia(filePath, 'image');
    return client.sendImage(to, { id: mediaId, caption });
  }
}

2. Batch Operations

✅ Good: Parallel Processing with Limits

async function sendBulkMessages(recipients: string[], message: string) {
  const BATCH_SIZE = 10; // Process 10 at a time
  
  for (let i = 0; i < recipients.length; i += BATCH_SIZE) {
    const batch = recipients.slice(i, i + BATCH_SIZE);
    
    await Promise.allSettled(
      batch.map(async (recipient) => {
        try {
          await client.sendText(recipient, message);
          console.log(`✅ Sent to ${recipient}`);
        } catch (error) {
          console.error(`❌ Failed to send to ${recipient}:`, error.message);
        }
      })
    );
    
    // Add delay between batches to respect rate limits
    if (i + BATCH_SIZE < recipients.length) {
      await new Promise(resolve => setTimeout(resolve, 1000));
    }
  }
}

3. Connection Management

✅ Good: Connection Testing

class WhatsAppService {
  private client: WhatsAppClient;
  private lastHealthCheck = 0;
  private readonly HEALTH_CHECK_INTERVAL = 5 * 60 * 1000; // 5 minutes
  
  constructor() {
    this.client = getWhatsAppClient();
  }
  
  async ensureConnection(): Promise<boolean> {
    const now = Date.now();
    
    if (now - this.lastHealthCheck > this.HEALTH_CHECK_INTERVAL) {
      try {
        const isConnected = await this.client.testConnection();
        this.lastHealthCheck = now;
        
        if (!isConnected) {
          console.error('❌ WhatsApp API connection failed');
          // Trigger alert/notification
          return false;
        }
        
        console.log('✅ WhatsApp API connection healthy');
        return true;
      } catch (error) {
        console.error('❌ Health check failed:', error.message);
        return false;
      }
    }
    
    return true;
  }
  
  async sendMessage(to: string, message: string): Promise<void> {
    if (!(await this.ensureConnection())) {
      throw new Error('WhatsApp API connection unavailable');
    }
    
    return this.client.sendText(to, message);
  }
}

🔒 Security Best Practices

1. Credential Management

✅ Good: Secure Configuration

// Use environment variables
const config = {
  accessToken: process.env.WHATSAPP_ACCESS_TOKEN!,
  phoneNumberId: process.env.WHATSAPP_PHONE_NUMBER_ID!,
  webhookVerifyToken: process.env.WHATSAPP_WEBHOOK_TOKEN!,
};

// Validate required environment variables
function validateEnvironment() {
  const required = ['WHATSAPP_ACCESS_TOKEN', 'WHATSAPP_PHONE_NUMBER_ID'];
  const missing = required.filter(key => !process.env[key]);
  
  if (missing.length > 0) {
    throw new Error(`Missing required environment variables: ${missing.join(', ')}`);
  }
}

validateEnvironment();

❌ Avoid: Hardcoded Credentials

// Never do this!
const client = new WhatsAppClient({
  accessToken: 'EAABsBCS...', // Hardcoded token
  phoneNumberId: '123456789',
});

2. Webhook Security

✅ Good: Proper Webhook Verification

const webhookProcessor = client.createWebhookProcessor({
  verifyToken: process.env.WHATSAPP_WEBHOOK_TOKEN!, // Always verify
  
  onTextMessage: async (message) => {
    // Message is verified by processor
    await handleSecureMessage(message);
  },
  
  onError: async (error, message) => {
    if (error.name === 'WebhookVerificationError') {
      console.error('🚨 Webhook verification failed:', error.message);
      // Alert security team
      await notifySecurityTeam(error);
    }
  }
});

3. Input Validation and Sanitization

✅ Good: Validate All Inputs

import { validatePhoneNumber, sanitizeText } from 'whatsapp-client-sdk';

function sendUserMessage(to: string, message: string) {
  // Validate phone number
  if (!validatePhoneNumber(to)) {
    throw new Error('Invalid phone number format');
  }
  
  // Sanitize message content
  const cleanMessage = sanitizeText(message);
  
  // Check message length
  if (cleanMessage.length > 4096) {
    throw new Error('Message too long');
  }
  
  // Check for forbidden content
  if (containsForbiddenContent(cleanMessage)) {
    throw new Error('Message contains forbidden content');
  }
  
  return client.sendText(to, cleanMessage);
}

function containsForbiddenContent(text: string): boolean {
  const forbiddenPatterns = [
    /spam/i,
    /phishing/i,
    /malware/i,
    // Add more patterns
  ];
  
  return forbiddenPatterns.some(pattern => pattern.test(text));
}

🛠️ Error Handling Patterns

For comprehensive error handling with enhanced error classes, detailed context, and actionable suggestions, see our Enhanced Error Handling Guide.

1. Comprehensive Error Handling

✅ Good: Specific Error Handling

async function robustMessageSend(to: string, message: string): Promise<void> {
  try {
    await client.sendText(to, message);
    console.log('✅ Message sent successfully');
    
  } catch (error) {
    if (error instanceof MessageValidationError) {
      console.error('❌ Message validation failed:', {
        field: error.field,
        message: error.message,
        value: error.value
      });
      
      // Handle specific validation errors
      if (error.field === 'to') {
        throw new Error('Please provide a valid phone number with country code');
      } else if (error.field === 'text.body') {
        throw new Error('Message content is invalid or too long');
      }
      
    } else if (error instanceof WhatsAppApiError) {
      console.error('❌ WhatsApp API error:', {
        status: error.status,
        code: error.code,
        details: error.details
      });
      
      // Handle specific API errors
      switch (error.code) {
        case 131:
          throw new Error('The phone number is not registered with WhatsApp');
        case 132:
          throw new Error('Message could not be delivered to this number');
        case 133:
          throw new Error('Message content violates WhatsApp policies');
        default:
          throw new Error(`WhatsApp service error: ${error.details}`);
      }
      
    } else if (error instanceof RateLimitError) {
      console.warn(`⏰ Rate limited. Retrying in ${error.retryAfter} seconds`);
      
      // Implement exponential backoff
      await new Promise(resolve => setTimeout(resolve, error.retryAfter * 1000));
      return robustMessageSend(to, message); // Retry once
      
    } else {
      console.error('💥 Unexpected error:', error);
      throw new Error('An unexpected error occurred while sending the message');
    }
  }
}

2. Retry Logic with Circuit Breaker

✅ Good: Smart Retry Strategy

class CircuitBreaker {
  private failures = 0;
  private lastFailTime = 0;
  private readonly maxFailures = 5;
  private readonly resetTimeout = 60000; // 1 minute
  
  async execute<T>(operation: () => Promise<T>): Promise<T> {
    if (this.isOpen()) {
      throw new Error('Circuit breaker is open');
    }
    
    try {
      const result = await operation();
      this.onSuccess();
      return result;
    } catch (error) {
      this.onFailure();
      throw error;
    }
  }
  
  private isOpen(): boolean {
    return this.failures >= this.maxFailures && 
           Date.now() - this.lastFailTime < this.resetTimeout;
  }
  
  private onSuccess(): void {
    this.failures = 0;
  }
  
  private onFailure(): void {
    this.failures++;
    this.lastFailTime = Date.now();
  }
}

const circuitBreaker = new CircuitBreaker();

async function sendWithCircuitBreaker(to: string, message: string) {
  return circuitBreaker.execute(() => client.sendText(to, message));
}

📊 Monitoring and Logging

1. Structured Logging

✅ Good: Comprehensive Logging

interface LogContext {
  operation: string;
  recipient?: string;
  messageId?: string;
  duration?: number;
  error?: any;
}

class Logger {
  static info(message: string, context: LogContext = {}) {
    console.log(JSON.stringify({
      level: 'info',
      message,
      timestamp: new Date().toISOString(),
      ...context
    }));
  }
  
  static error(message: string, context: LogContext = {}) {
    console.error(JSON.stringify({
      level: 'error',
      message,
      timestamp: new Date().toISOString(),
      ...context
    }));
  }
}

async function loggedSendText(to: string, text: string): Promise<MessageResponse> {
  const startTime = Date.now();
  const context: LogContext = { operation: 'sendText', recipient: to };
  
  try {
    Logger.info('Sending text message', context);
    
    const response = await client.sendText(to, text);
    
    Logger.info('Text message sent successfully', {
      ...context,
      messageId: response.messages[0].id,
      duration: Date.now() - startTime
    });
    
    return response;
    
  } catch (error) {
    Logger.error('Failed to send text message', {
      ...context,
      duration: Date.now() - startTime,
      error: {
        name: error.name,
        message: error.message,
        ...(error instanceof WhatsAppApiError && {
          code: error.code,
          status: error.status
        })
      }
    });
    
    throw error;
  }
}

2. Metrics Collection

✅ Good: Business Metrics

class MetricsCollector {
  private static metrics = {
    messagesSent: 0,
    messagesDelivered: 0,
    messagesFailed: 0,
    apiErrors: new Map<number, number>(),
    averageResponseTime: 0,
    responseTimes: [] as number[]
  };
  
  static recordMessageSent(): void {
    this.metrics.messagesSent++;
  }
  
  static recordMessageDelivered(): void {
    this.metrics.messagesDelivered++;
  }
  
  static recordMessageFailed(errorCode?: number): void {
    this.metrics.messagesFailed++;
    
    if (errorCode) {
      const current = this.metrics.apiErrors.get(errorCode) || 0;
      this.metrics.apiErrors.set(errorCode, current + 1);
    }
  }
  
  static recordResponseTime(duration: number): void {
    this.metrics.responseTimes.push(duration);
    
    // Keep only last 100 measurements
    if (this.metrics.responseTimes.length > 100) {
      this.metrics.responseTimes.shift();
    }
    
    // Update average
    this.metrics.averageResponseTime = 
      this.metrics.responseTimes.reduce((a, b) => a + b) / 
      this.metrics.responseTimes.length;
  }
  
  static getMetrics() {
    return {
      ...this.metrics,
      deliveryRate: this.metrics.messagesDelivered / this.metrics.messagesSent,
      errorRate: this.metrics.messagesFailed / this.metrics.messagesSent
    };
  }
}

💾 Storage Best Practices

1. Enable Storage for Message History

Store messages for analytics and compliance:

const client = new WhatsAppClient({
  accessToken: process.env.WHATSAPP_ACCESS_TOKEN!,
  phoneNumberId: process.env.WHATSAPP_PHONE_NUMBER_ID!,

  storage: {
    enabled: true,
    provider: 'supabase',
    options: {
      url: process.env.SUPABASE_URL!,
      apiKey: process.env.SUPABASE_KEY! // Use Service Role Key
    },
    features: {
      persistIncoming: true,
      persistOutgoing: true,
      persistStatus: true,
      retentionDays: 90 // Auto-delete after 90 days
    }
  }
});

await client.initializeStorage();

Complete Storage Guide

Learn about storage configuration, querying, and security best practices

2. Query Message History

Access stored conversations:

// Get conversation history
const conversation = await client.getConversation('+1234567890', {
  limit: 50
});

// Search messages
const results = await client.searchMessages({
  text: 'order',
  phoneNumber: '+1234567890'
});

// Get analytics
const analytics = await client.getConversationAnalytics('+1234567890');
console.log('Response rate:', analytics.responseRate);

3. Data Security

✅ Use Service Role Key only in backend
✅ Never expose database credentials in frontend
✅ Enable Row Level Security (RLS) in Supabase
✅ Implement data retention policies
✅ Encrypt sensitive message content

Storage Security Guide

Complete security and performance best practices for storage

🔄 Webhook Best Practices

1. Idempotent Processing

✅ Good: Handle Duplicate Messages

const processedMessages = new Set<string>();

const webhookProcessor = client.createWebhookProcessor({
  onTextMessage: async (message) => {
    // Check if message already processed
    if (processedMessages.has(message.id)) {
      console.log('Duplicate message, skipping:', message.id);
      return;
    }
    
    try {
      await processMessage(message);
      processedMessages.add(message.id);
      
      // Clean up old message IDs (keep last 1000)
      if (processedMessages.size > 1000) {
        const oldestId = processedMessages.values().next().value;
        processedMessages.delete(oldestId);
      }
      
    } catch (error) {
      console.error('Error processing message:', error);
      // Don't add to processed set on error, allow retry
    }
  }
});

2. Async Processing

✅ Good: Quick Response with Background Processing

import Queue from 'bull';

const messageQueue = new Queue('message processing');

const webhookProcessor = client.createWebhookProcessor({
  onTextMessage: async (message) => {
    // Quick acknowledgment
    await client.sendText(message.from, '✅ Message received! Processing...');
    
    // Add to background queue
    await messageQueue.add('processMessage', message);
  }
});

// Background processor
messageQueue.process('processMessage', async (job) => {
  const message = job.data;
  
  try {
    // Complex processing
    const result = await complexMessageProcessing(message);
    
    // Send result back to user
    await client.sendText(message.from, `✅ Processed: ${result}`);
    
  } catch (error) {
    console.error('Background processing failed:', error);
    await client.sendText(
      message.from, 
      '❌ Processing failed. Our team has been notified.'
    );
  }
});

📈 Scalability Patterns

1. Horizontal Scaling

✅ Good: Stateless Design

// Use external storage instead of in-memory state
import Redis from 'ioredis';

const redis = new Redis(process.env.REDIS_URL!);

class ScalableConversationManager {
  async getConversationState(userId: string): Promise<any> {
    const state = await redis.get(`conversation:${userId}`);
    return state ? JSON.parse(state) : { step: 'start' };
  }
  
  async setConversationState(userId: string, state: any): Promise<void> {
    await redis.setex(`conversation:${userId}`, 3600, JSON.stringify(state));
  }
  
  async clearConversationState(userId: string): Promise<void> {
    await redis.del(`conversation:${userId}`);
  }
}

const conversationManager = new ScalableConversationManager();

const webhookProcessor = client.createWebhookProcessor({
  onTextMessage: async (message) => {
    const state = await conversationManager.getConversationState(message.from);
    
    // Process based on state
    const newState = await processConversationStep(message, state);
    
    if (newState.completed) {
      await conversationManager.clearConversationState(message.from);
    } else {
      await conversationManager.setConversationState(message.from, newState);
    }
  }
});

2. Load Balancing

✅ Good: Multiple Webhook Endpoints

// webhook-1.js, webhook-2.js, etc.
const instanceId = process.env.INSTANCE_ID || 'default';

const webhookProcessor = client.createWebhookProcessor({
  onTextMessage: async (message) => {
    console.log(`Processing on instance ${instanceId}:`, message.id);
    await processMessage(message);
  },
  
  onError: async (error, message) => {
    console.error(`Error on instance ${instanceId}:`, error.message);
  }
});

Examples

Guides

🏗️ Architecture Best Practices

1. Client Initialization

2. Environment Configuration

📱 Message Best Practices

1. Message Content Guidelines

2. Message Formatting

3. Interactive Message Design

⚡ Performance Optimization

1. Media Management

2. Batch Operations

3. Connection Management

🔒 Security Best Practices

1. Credential Management

2. Webhook Security

3. Input Validation and Sanitization

🛠️ Error Handling Patterns

1. Comprehensive Error Handling

2. Retry Logic with Circuit Breaker

📊 Monitoring and Logging

1. Structured Logging

2. Metrics Collection

💾 Storage Best Practices

1. Enable Storage for Message History

Complete Storage Guide

2. Query Message History

3. Data Security

Storage Security Guide

🔄 Webhook Best Practices

1. Idempotent Processing

2. Async Processing

📈 Scalability Patterns

1. Horizontal Scaling

2. Load Balancing

​🏗️ Architecture Best Practices

​1. Client Initialization

​2. Environment Configuration

​📱 Message Best Practices

​1. Message Content Guidelines

​2. Message Formatting

​3. Interactive Message Design

​⚡ Performance Optimization

​1. Media Management

​2. Batch Operations

​3. Connection Management

​🔒 Security Best Practices

​1. Credential Management

​2. Webhook Security

​3. Input Validation and Sanitization

​🛠️ Error Handling Patterns

​1. Comprehensive Error Handling

​2. Retry Logic with Circuit Breaker

​📊 Monitoring and Logging

​1. Structured Logging

​2. Metrics Collection

​💾 Storage Best Practices

​1. Enable Storage for Message History

Complete Storage Guide

​2. Query Message History

​3. Data Security

Storage Security Guide

​🔄 Webhook Best Practices

​1. Idempotent Processing

​2. Async Processing

​📈 Scalability Patterns

​1. Horizontal Scaling

​2. Load Balancing

🏗️ Architecture Best Practices

1. Client Initialization

2. Environment Configuration

📱 Message Best Practices

1. Message Content Guidelines

2. Message Formatting

3. Interactive Message Design

⚡ Performance Optimization

1. Media Management

2. Batch Operations

3. Connection Management

🔒 Security Best Practices

1. Credential Management

2. Webhook Security

3. Input Validation and Sanitization

🛠️ Error Handling Patterns

1. Comprehensive Error Handling

2. Retry Logic with Circuit Breaker

📊 Monitoring and Logging

1. Structured Logging

2. Metrics Collection

💾 Storage Best Practices

1. Enable Storage for Message History

2. Query Message History

3. Data Security

🔄 Webhook Best Practices

1. Idempotent Processing

2. Async Processing

📈 Scalability Patterns

1. Horizontal Scaling

2. Load Balancing