Initial commit: Telegram Management System

Full-stack web application for Telegram management
- Frontend: Vue 3 + Vben Admin
- Backend: NestJS
- Features: User management, group broadcast, statistics

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

marketing-agent/services/billing-service/src/middleware/validation.js

@@ -0,0 +1,104 @@
+import { validationResult } from 'express-validator';
+import { logger } from '../utils/logger.js';
+
+// Validate request middleware
+export const validateRequest = (validations) => {
+  return async (req, res, next) => {
+    // Run all validations
+    await Promise.all(validations.map(validation => validation.run(req)));
+
+    const errors = validationResult(req);
+    if (errors.isEmpty()) {
+      return next();
+    }
+
+    const extractedErrors = [];
+    errors.array().map(err => extractedErrors.push({ 
+      field: err.path,
+      message: err.msg,
+      value: err.value 
+    }));
+
+    logger.warn('Validation errors', { 
+      path: req.path,
+      errors: extractedErrors 
+    });
+
+    return res.status(400).json({
+      success: false,
+      error: 'Validation failed',
+      errors: extractedErrors
+    });
+  };
+};
+
+// Custom validators
+export const validators = {
+  // Validate MongoDB ObjectId
+  isMongoId: (value) => {
+    const mongoIdRegex = /^[0-9a-fA-F]{24}$/;
+    return mongoIdRegex.test(value);
+  },
+
+  // Validate currency code
+  isCurrency: (value) => {
+    const validCurrencies = ['USD', 'EUR', 'GBP', 'JPY', 'CAD', 'AUD', 'CNY'];
+    return validCurrencies.includes(value.toUpperCase());
+  },
+
+  // Validate credit card number (basic check)
+  isCreditCard: (value) => {
+    const cardRegex = /^[0-9]{13,19}$/;
+    return cardRegex.test(value.replace(/\s/g, ''));
+  },
+
+  // Validate phone number
+  isPhoneNumber: (value) => {
+    const phoneRegex = /^\+?[1-9]\d{1,14}$/;
+    return phoneRegex.test(value);
+  },
+
+  // Validate date range
+  isValidDateRange: (startDate, endDate) => {
+    const start = new Date(startDate);
+    const end = new Date(endDate);
+    return start <= end;
+  },
+
+  // Validate billing cycle
+  isBillingCycle: (value) => {
+    const validCycles = ['monthly', 'quarterly', 'yearly'];
+    return validCycles.includes(value);
+  },
+
+  // Validate plan type
+  isPlanType: (value) => {
+    const validPlans = ['free', 'starter', 'professional', 'enterprise', 'custom'];
+    return validPlans.includes(value);
+  }
+};
+
+// Sanitization helpers
+export const sanitize = {
+  // Clean string input
+  cleanString: (value) => {
+    if (typeof value !== 'string') return value;
+    return value.trim().replace(/[<>]/g, '');
+  },
+
+  // Format currency amount
+  formatAmount: (value) => {
+    const amount = parseFloat(value);
+    return Math.round(amount * 100) / 100;
+  },
+
+  // Normalize email
+  normalizeEmail: (email) => {
+    return email.toLowerCase().trim();
+  },
+
+  // Clean credit card number
+  cleanCardNumber: (value) => {
+    return value.replace(/\s/g, '').replace(/-/g, '');
+  }
+};