feat: add Queue-based async server provisioning

- Add Cloudflare Queue for async server provisioning workflow - Implement VPS provider abstraction (Linode, Vultr) - Add provisioning API endpoints with API key authentication - Fix race condition in balance deduction (atomic query) - Remove root_password from Queue for security (fetch from DB) - Add IP assignment wait logic after server creation - Add rollback/refund on all failure cases Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2026-01-27 17:19:19 +09:00
parent 8c543eeaa5
commit 9b51b8d427
12 changed files with 1796 additions and 5 deletions
--- a/src/handlers/provision.ts
+++ b/src/handlers/provision.ts
@@ -0,0 +1,354 @@
+/**
+ * Server Provisioning Handler
+ * POST /api/provision - Create a new server
+ * GET /api/provision/orders - Get user's orders
+ * GET /api/provision/orders/:id - Get specific order
+ * DELETE /api/provision/orders/:id - Delete/terminate server
+ * GET /api/provision/balance - Get user's balance
+ */
+
+import type { Env, ProvisionRequest } from '../types';
+import { ProvisioningService } from '../services/provisioning-service';
+import { createErrorResponse, createSuccessResponse } from '../utils/http';
+import { LIMITS } from '../config';
+
+/**
+ * Validate provision request body
+ * Note: user_id in API is the Telegram ID
+ */
+function validateProvisionRequest(body: unknown): {
+  valid: true;
+  data: ProvisionRequest;
+} | {
+  valid: false;
+  error: string;
+} {
+  if (!body || typeof body !== 'object') {
+    return { valid: false, error: 'Request body must be a JSON object' };
+  }
+
+  const data = body as Record<string, unknown>;
+
+  // Required fields - user_id is the Telegram ID
+  if (!data.user_id || typeof data.user_id !== 'string') {
+    return { valid: false, error: 'user_id is required and must be a string (Telegram ID)' };
+  }
+
+  if (!data.pricing_id || typeof data.pricing_id !== 'number' || data.pricing_id <= 0) {
+    return { valid: false, error: 'pricing_id is required and must be a positive number' };
+  }
+
+  // Optional fields validation
+  if (data.label !== undefined && typeof data.label !== 'string') {
+    return { valid: false, error: 'label must be a string' };
+  }
+
+  if (data.label && (data.label as string).length > 64) {
+    return { valid: false, error: 'label must be 64 characters or less' };
+  }
+
+  const validOsImages = ['ubuntu_22_04', 'ubuntu_20_04', 'debian_11', 'debian_12'];
+  if (data.image !== undefined && !validOsImages.includes(data.image as string)) {
+    return { valid: false, error: `image must be one of: ${validOsImages.join(', ')}` };
+  }
+
+  if (data.dry_run !== undefined && typeof data.dry_run !== 'boolean') {
+    return { valid: false, error: 'dry_run must be a boolean' };
+  }
+
+  return {
+    valid: true,
+    data: {
+      telegram_id: data.user_id as string, // API uses user_id, internally it's telegram_id
+      pricing_id: data.pricing_id as number,
+      label: data.label as string | undefined,
+      image: data.image as string | undefined,
+      dry_run: data.dry_run as boolean | undefined,
+    },
+  };
+}
+
+/**
+ * POST /api/provision
+ * Create a new server
+ */
+export async function handleProvision(
+  request: Request,
+  env: Env,
+  corsHeaders: Record<string, string>
+): Promise<Response> {
+  try {
+    // Check content length
+    const contentLength = request.headers.get('content-length');
+    if (contentLength && parseInt(contentLength, 10) > LIMITS.MAX_REQUEST_BODY_BYTES) {
+      return createErrorResponse('Request body too large', 413, undefined, corsHeaders);
+    }
+
+    // Parse request body
+    let body: unknown;
+    try {
+      body = await request.json();
+    } catch {
+      return createErrorResponse('Invalid JSON in request body', 400, undefined, corsHeaders);
+    }
+
+    // Validate request
+    const validation = validateProvisionRequest(body);
+    if (!validation.valid) {
+      return createErrorResponse(validation.error, 400, 'VALIDATION_ERROR', corsHeaders);
+    }
+
+    // Check API keys (skip for dry_run)
+    if (!validation.data.dry_run && !env.LINODE_API_KEY && !env.VULTR_API_KEY) {
+      return createErrorResponse(
+        'No VPS provider API keys configured',
+        503,
+        'SERVICE_UNAVAILABLE',
+        corsHeaders
+      );
+    }
+
+    // Create provisioning service with both DBs
+    const provisioningService = new ProvisioningService(
+      env,          // Full env for exchange rate
+      env.DB,       // cloud-instances-db
+      env.USER_DB,  // telegram-conversations
+      env.LINODE_API_KEY,
+      env.VULTR_API_KEY
+    );
+
+    // Provision server
+    const result = await provisioningService.provisionServer(validation.data);
+
+    if (!result.success) {
+      // Map error codes to HTTP status codes
+      const statusCode = getStatusCodeForError(result.error!.code);
+      return createErrorResponse(
+        result.error!.message,
+        statusCode,
+        result.error!.code,
+        corsHeaders
+      );
+    }
+
+    // Return success response (hide root password in response)
+    const sanitizedOrder = {
+      ...result.order!,
+      root_password: '*** Use GET /api/provision/orders/:id to retrieve once ***',
+    };
+
+    // Include dry_run_info if present
+    const response: Record<string, unknown> = {
+      message: validation.data.dry_run
+        ? 'Dry run successful. Validation passed.'
+        : 'Server provisioned successfully',
+      order: sanitizedOrder,
+    };
+
+    // Add dry_run details from service
+    if ('dry_run_info' in result) {
+      response.dry_run_info = (result as Record<string, unknown>).dry_run_info;
+    }
+
+    return createSuccessResponse(response, validation.data.dry_run ? 200 : 201, corsHeaders);
+  } catch (error) {
+    console.error('[handleProvision] Error:', error);
+    return createErrorResponse(
+      'Internal server error during provisioning',
+      500,
+      'INTERNAL_ERROR',
+      corsHeaders
+    );
+  }
+}
+
+/**
+ * GET /api/provision/orders
+ * Get user's orders
+ */
+export async function handleGetOrders(
+  request: Request,
+  env: Env,
+  corsHeaders: Record<string, string>
+): Promise<Response> {
+  try {
+    const url = new URL(request.url);
+    const userId = url.searchParams.get('user_id'); // This is telegram_id
+
+    if (!userId) {
+      return createErrorResponse('user_id query parameter is required', 400, undefined, corsHeaders);
+    }
+
+    const provisioningService = new ProvisioningService(
+      env,
+      env.DB,
+      env.USER_DB,
+      env.LINODE_API_KEY,
+      env.VULTR_API_KEY
+    );
+
+    const orders = await provisioningService.getUserOrders(userId);
+
+    // Sanitize root passwords
+    const sanitizedOrders = orders.map((order) => ({
+      ...order,
+      root_password: order.root_password ? '***REDACTED***' : null,
+    }));
+
+    return createSuccessResponse({ orders: sanitizedOrders }, 200, corsHeaders);
+  } catch (error) {
+    console.error('[handleGetOrders] Error:', error);
+    return createErrorResponse('Internal server error', 500, undefined, corsHeaders);
+  }
+}
+
+/**
+ * GET /api/provision/orders/:id
+ * Get specific order with root password (one-time view concept)
+ */
+export async function handleGetOrder(
+  request: Request,
+  env: Env,
+  orderId: string,
+  corsHeaders: Record<string, string>
+): Promise<Response> {
+  try {
+    const url = new URL(request.url);
+    const userId = url.searchParams.get('user_id'); // This is telegram_id
+
+    if (!userId) {
+      return createErrorResponse('user_id query parameter is required', 400, undefined, corsHeaders);
+    }
+
+    const provisioningService = new ProvisioningService(
+      env,
+      env.DB,
+      env.USER_DB,
+      env.LINODE_API_KEY,
+      env.VULTR_API_KEY
+    );
+
+    const order = await provisioningService.getOrder(orderId);
+
+    if (!order) {
+      return createErrorResponse('Order not found', 404, 'NOT_FOUND', corsHeaders);
+    }
+
+    // Get user to verify ownership
+    const balance = await provisioningService.getUserBalance(userId);
+    if (!balance || order.user_id !== balance.user_id) {
+      return createErrorResponse('Unauthorized', 403, 'UNAUTHORIZED', corsHeaders);
+    }
+
+    // Include root password for order owner
+    return createSuccessResponse({ order }, 200, corsHeaders);
+  } catch (error) {
+    console.error('[handleGetOrder] Error:', error);
+    return createErrorResponse('Internal server error', 500, undefined, corsHeaders);
+  }
+}
+
+/**
+ * DELETE /api/provision/orders/:id
+ * Delete/terminate a server
+ */
+export async function handleDeleteOrder(
+  request: Request,
+  env: Env,
+  orderId: string,
+  corsHeaders: Record<string, string>
+): Promise<Response> {
+  try {
+    const url = new URL(request.url);
+    const userId = url.searchParams.get('user_id'); // This is telegram_id
+
+    if (!userId) {
+      return createErrorResponse('user_id query parameter is required', 400, undefined, corsHeaders);
+    }
+
+    const provisioningService = new ProvisioningService(
+      env,
+      env.DB,
+      env.USER_DB,
+      env.LINODE_API_KEY,
+      env.VULTR_API_KEY
+    );
+
+    const result = await provisioningService.deleteServer(orderId, userId);
+
+    if (!result.success) {
+      return createErrorResponse(result.error!, 400, 'DELETE_FAILED', corsHeaders);
+    }
+
+    return createSuccessResponse({ message: 'Server terminated successfully' }, 200, corsHeaders);
+  } catch (error) {
+    console.error('[handleDeleteOrder] Error:', error);
+    return createErrorResponse('Internal server error', 500, undefined, corsHeaders);
+  }
+}
+
+/**
+ * GET /api/provision/balance
+ * Get user's balance (in KRW)
+ */
+export async function handleGetBalance(
+  request: Request,
+  env: Env,
+  corsHeaders: Record<string, string>
+): Promise<Response> {
+  try {
+    const url = new URL(request.url);
+    const userId = url.searchParams.get('user_id'); // This is telegram_id
+
+    if (!userId) {
+      return createErrorResponse('user_id query parameter is required', 400, undefined, corsHeaders);
+    }
+
+    const provisioningService = new ProvisioningService(
+      env,
+      env.DB,
+      env.USER_DB,
+      env.LINODE_API_KEY,
+      env.VULTR_API_KEY
+    );
+
+    const balance = await provisioningService.getUserBalance(userId);
+
+    if (!balance) {
+      return createErrorResponse('User not found', 404, 'NOT_FOUND', corsHeaders);
+    }
+
+    return createSuccessResponse(
+      {
+        balance_krw: balance.balance_krw,
+        currency: 'KRW',
+      },
+      200,
+      corsHeaders
+    );
+  } catch (error) {
+    console.error('[handleGetBalance] Error:', error);
+    return createErrorResponse('Internal server error', 500, undefined, corsHeaders);
+  }
+}
+
+/**
+ * Map error codes to HTTP status codes
+ */
+function getStatusCodeForError(code: string): number {
+  switch (code) {
+    case 'USER_NOT_FOUND':
+    case 'PRICING_NOT_FOUND':
+      return 404;
+    case 'INSUFFICIENT_BALANCE':
+      return 402; // Payment Required
+    case 'PROVIDER_NOT_CONFIGURED':
+      return 503;
+    case 'VALIDATION_ERROR':
+      return 400;
+    case 'UNAUTHORIZED':
+      return 403;
+    default:
+      return 500;
+  }
+}
--- a/src/handlers/queue.ts
+++ b/src/handlers/queue.ts
@@ -0,0 +1,41 @@
+/**
+ * Queue Handler for async server provisioning
+ * Processes messages from PROVISION_QUEUE
+ */
+
+import type { Env, ProvisionQueueMessage } from '../types';
+import { ProvisioningService } from '../services/provisioning-service';
+
+/**
+ * Queue message handler
+ * Called by Cloudflare Workers Queue consumer
+ */
+export async function handleProvisionQueue(
+  batch: MessageBatch<ProvisionQueueMessage>,
+  env: Env
+): Promise<void> {
+  const provisioningService = new ProvisioningService(
+    env,
+    env.DB,
+    env.USER_DB,
+    env.LINODE_API_KEY,
+    env.VULTR_API_KEY
+  );
+
+  for (const message of batch.messages) {
+    try {
+      console.log(`[Queue] Processing message for order ${message.body.order_id}`);
+
+      await provisioningService.processQueueMessage(message.body);
+
+      // Acknowledge successful processing
+      message.ack();
+      console.log(`[Queue] Order ${message.body.order_id} processed successfully`);
+    } catch (error) {
+      console.error(`[Queue] Error processing order ${message.body.order_id}:`, error);
+
+      // Retry the message (will go to DLQ after max_retries)
+      message.retry();
+    }
+  }
+}
--- a/src/index.ts
+++ b/src/index.ts
@@ -5,11 +5,20 @@
 */

 import type { Env } from './types';
-import { getAllowedOrigin, checkRateLimit, jsonResponse } from './utils';
+import { getAllowedOrigin, checkRateLimit, jsonResponse, isAllowedProvisionOrigin } from './utils';
 import { handleHealth } from './handlers/health';
 import { handleGetServers } from './handlers/servers';
 import { handleRecommend } from './handlers/recommend';
 import { handleReport } from './handlers/report';
+import {
+  handleProvision,
+  handleGetOrders,
+  handleGetOrder,
+  handleDeleteOrder,
+  handleGetBalance,
+} from './handlers/provision';
+import { handleProvisionQueue } from './handlers/queue';
+import type { ProvisionQueueMessage } from './types';

 /**
 * Main request handler
@@ -44,7 +53,7 @@ export default {
      const origin = getAllowedOrigin(request);
      const corsHeaders = {
        'Access-Control-Allow-Origin': origin,
-        'Access-Control-Allow-Methods': 'GET, POST, OPTIONS',
+        'Access-Control-Allow-Methods': 'GET, POST, DELETE, OPTIONS',
        'Access-Control-Allow-Headers': 'Content-Type',
        'Vary': 'Origin',
      };
@@ -71,6 +80,52 @@ export default {
        return handleReport(request, env, corsHeaders);
      }

+      // Provisioning endpoints (restricted to *.kappa-d8e.workers.dev + API key)
+      if (path.startsWith('/api/provision')) {
+        // Check API key (required for all provision requests)
+        const apiKey = request.headers.get('X-API-Key');
+        if (!env.PROVISION_API_KEY || apiKey !== env.PROVISION_API_KEY) {
+          return jsonResponse(
+            { error: 'Unauthorized: Invalid or missing API key', code: 'UNAUTHORIZED' },
+            401,
+            corsHeaders
+          );
+        }
+
+        // Check origin for browser requests
+        if (!isAllowedProvisionOrigin(request)) {
+          return jsonResponse(
+            { error: 'Forbidden: Invalid origin', code: 'FORBIDDEN' },
+            403,
+            corsHeaders
+          );
+        }
+
+        if (path === '/api/provision' && request.method === 'POST') {
+          return handleProvision(request, env, corsHeaders);
+        }
+
+        if (path === '/api/provision/orders' && request.method === 'GET') {
+          return handleGetOrders(request, env, corsHeaders);
+        }
+
+        if (path === '/api/provision/balance' && request.method === 'GET') {
+          return handleGetBalance(request, env, corsHeaders);
+        }
+
+        // Dynamic route: /api/provision/orders/:id
+        const orderMatch = path.match(/^\/api\/provision\/orders\/([a-zA-Z0-9-]+)$/);
+        if (orderMatch) {
+          const orderId = orderMatch[1];
+          if (request.method === 'GET') {
+            return handleGetOrder(request, env, orderId, corsHeaders);
+          }
+          if (request.method === 'DELETE') {
+            return handleDeleteOrder(request, env, orderId, corsHeaders);
+          }
+        }
+      }
+
      return jsonResponse(
        { error: 'Not found', request_id: requestId },
        404,
@@ -92,4 +147,11 @@ export default {
      );
    }
  },
+
+  /**
+   * Queue handler for async server provisioning
+   */
+  async queue(batch: MessageBatch<ProvisionQueueMessage>, env: Env): Promise<void> {
+    await handleProvisionQueue(batch, env);
+  },
 };
--- a/src/repositories/ProvisioningRepository.ts
+++ b/src/repositories/ProvisioningRepository.ts
@@ -0,0 +1,272 @@
+/**
+ * Repository for provisioning-related database operations
+ * Uses two databases:
+ * - DB (cloud-instances-db): server specs, pricing, providers
+ * - USER_DB (telegram-conversations): users, deposits, orders
+ */
+
+import type { TelegramUser, UserDeposit, ServerOrder, PricingWithProvider } from '../types';
+
+export class ProvisioningRepository {
+  constructor(
+    private db: D1Database,        // cloud-instances-db
+    private userDb: D1Database     // telegram-conversations
+  ) {}
+
+  // ============================================
+  // User Operations (telegram-conversations.users)
+  // ============================================
+
+  async getUserByTelegramId(telegramId: string): Promise<TelegramUser | null> {
+    const result = await this.userDb
+      .prepare('SELECT * FROM users WHERE telegram_id = ?')
+      .bind(telegramId)
+      .first();
+
+    return result as unknown as TelegramUser | null;
+  }
+
+  async getUserById(userId: number): Promise<TelegramUser | null> {
+    const result = await this.userDb
+      .prepare('SELECT * FROM users WHERE id = ?')
+      .bind(userId)
+      .first();
+
+    return result as unknown as TelegramUser | null;
+  }
+
+  // ============================================
+  // Deposit Operations (telegram-conversations.user_deposits)
+  // Balance is in KRW (원), INTEGER type
+  // ============================================
+
+  async getUserDeposit(userId: number): Promise<UserDeposit | null> {
+    const result = await this.userDb
+      .prepare('SELECT * FROM user_deposits WHERE user_id = ?')
+      .bind(userId)
+      .first();
+
+    return result as unknown as UserDeposit | null;
+  }
+
+  async getBalance(userId: number): Promise<number> {
+    const deposit = await this.getUserDeposit(userId);
+    return deposit?.balance ?? 0;
+  }
+
+  async deductBalance(userId: number, amount: number): Promise<boolean> {
+    // Atomic balance deduction - prevents race condition
+    const result = await this.userDb
+      .prepare(
+        `UPDATE user_deposits
+         SET balance = balance - ?, updated_at = datetime('now')
+         WHERE user_id = ? AND balance >= ?
+         RETURNING balance`
+      )
+      .bind(amount, userId, amount)
+      .first();
+
+    // If no row returned, balance was insufficient
+    return result !== null;
+  }
+
+  async refundBalance(userId: number, amount: number): Promise<void> {
+    await this.userDb
+      .prepare(
+        `UPDATE user_deposits
+         SET balance = balance + ?, updated_at = datetime('now')
+         WHERE user_id = ?`
+      )
+      .bind(amount, userId)
+      .run();
+  }
+
+  // ============================================
+  // Server Order Operations (telegram-conversations.server_orders)
+  // ============================================
+
+  async createServerOrder(
+    userId: number,
+    specId: number,
+    region: string,
+    pricePaid: number,
+    label: string | null,
+    image: string | null
+  ): Promise<ServerOrder> {
+    const result = await this.userDb
+      .prepare(
+        `INSERT INTO server_orders
+         (user_id, spec_id, status, region, price_paid, label, image, billing_type)
+         VALUES (?, ?, 'pending', ?, ?, ?, ?, 'monthly')
+         RETURNING *`
+      )
+      .bind(userId, specId, region, pricePaid, label, image)
+      .first();
+
+    return result as unknown as ServerOrder;
+  }
+
+  async updateOrderStatus(
+    orderId: number,
+    status: ServerOrder['status'],
+    errorMessage?: string
+  ): Promise<void> {
+    if (errorMessage) {
+      await this.userDb
+        .prepare(
+          `UPDATE server_orders
+           SET status = ?, error_message = ?, updated_at = datetime('now')
+           WHERE id = ?`
+        )
+        .bind(status, errorMessage, orderId)
+        .run();
+    } else {
+      await this.userDb
+        .prepare(
+          `UPDATE server_orders
+           SET status = ?, updated_at = datetime('now')
+           WHERE id = ?`
+        )
+        .bind(status, orderId)
+        .run();
+    }
+  }
+
+  async updateOrderRootPassword(orderId: number, rootPassword: string): Promise<void> {
+    await this.userDb
+      .prepare(
+        `UPDATE server_orders
+         SET root_password = ?, updated_at = datetime('now')
+         WHERE id = ?`
+      )
+      .bind(rootPassword, orderId)
+      .run();
+  }
+
+  async updateOrderProviderInfo(
+    orderId: number,
+    providerInstanceId: string,
+    ipAddress: string | null,
+    rootPassword: string
+  ): Promise<void> {
+    await this.userDb
+      .prepare(
+        `UPDATE server_orders
+         SET provider_instance_id = ?,
+             ip_address = ?,
+             root_password = ?,
+             status = 'active',
+             provisioned_at = datetime('now'),
+             updated_at = datetime('now')
+         WHERE id = ?`
+      )
+      .bind(providerInstanceId, ipAddress, rootPassword, orderId)
+      .run();
+  }
+
+  async getOrderById(orderId: number): Promise<ServerOrder | null> {
+    const result = await this.userDb
+      .prepare('SELECT * FROM server_orders WHERE id = ?')
+      .bind(orderId)
+      .first();
+
+    return result as unknown as ServerOrder | null;
+  }
+
+  async getOrdersByUserId(userId: number, limit: number = 20): Promise<ServerOrder[]> {
+    const result = await this.userDb
+      .prepare(
+        'SELECT * FROM server_orders WHERE user_id = ? ORDER BY created_at DESC LIMIT ?'
+      )
+      .bind(userId, limit)
+      .all();
+
+    return result.results as unknown as ServerOrder[];
+  }
+
+  // ============================================
+  // Pricing Lookup (cloud-instances-db)
+  // Uses anvil_pricing, anvil_instances, anvil_regions
+  // ============================================
+
+  async getPricingWithProvider(pricingId: number): Promise<PricingWithProvider | null> {
+    const result = await this.db
+      .prepare(
+        `SELECT
+           ap.id as pricing_id,
+           0 as provider_id,
+           'Anvil' as provider_name,
+           'https://api.anvil.cloud' as api_base_url,
+           ai.name as instance_id,
+           ai.display_name as instance_name,
+           ar.name as region_code,
+           ar.display_name as region_name,
+           ap.monthly_price,
+           ai.vcpus as vcpu,
+           CAST(ai.memory_gb * 1024 AS INTEGER) as memory_mb,
+           ai.disk_gb as storage_gb
+         FROM anvil_pricing ap
+         JOIN anvil_instances ai ON ap.anvil_instance_id = ai.id
+         JOIN anvil_regions ar ON ap.anvil_region_id = ar.id
+         WHERE ap.id = ? AND ai.active = 1 AND ar.active = 1`
+      )
+      .bind(pricingId)
+      .first();
+
+    return result as unknown as PricingWithProvider | null;
+  }
+
+  // ============================================
+  // Atomic Operations (balance deduction + order creation)
+  // ============================================
+
+  /**
+   * Deduct balance and create order atomically
+   * Returns order ID on success, null on insufficient balance
+   */
+  async createOrderWithPayment(
+    userId: number,
+    specId: number,
+    region: string,
+    priceKrw: number,
+    label: string | null,
+    image: string | null
+  ): Promise<{ orderId: number | null; error?: string }> {
+    try {
+      // Step 1: Check and deduct balance
+      const deducted = await this.deductBalance(userId, priceKrw);
+      if (!deducted) {
+        return { orderId: null, error: 'INSUFFICIENT_BALANCE' };
+      }
+
+      // Step 2: Create order
+      const order = await this.createServerOrder(
+        userId,
+        specId,
+        region,
+        priceKrw,
+        label,
+        image
+      );
+
+      return { orderId: order.id };
+    } catch (error) {
+      // Attempt to refund on error
+      try {
+        await this.refundBalance(userId, priceKrw);
+      } catch {
+        // Log but don't throw - manual intervention needed
+        console.error('[ProvisioningRepository] Failed to refund on error:', error);
+      }
+      return { orderId: null, error: 'ORDER_CREATION_FAILED' };
+    }
+  }
+
+  /**
+   * Refund balance and update order status on provisioning failure
+   */
+  async rollbackOrder(orderId: number, userId: number, amount: number, errorMessage: string): Promise<void> {
+    await this.refundBalance(userId, amount);
+    await this.updateOrderStatus(orderId, 'failed', errorMessage);
+  }
+}
--- a/src/services/linode-provider.ts
+++ b/src/services/linode-provider.ts
@@ -0,0 +1,159 @@
+/**
+ * Linode VPS Provider Implementation
+ * API Docs: https://www.linode.com/docs/api/
+ */
+
+import type { VPSProviderConfig, CreateServerRequest, CreateServerResponse } from '../types';
+import { VPSProviderBase, OS_IMAGE_MAP } from './vps-provider';
+
+interface LinodeInstance {
+  id: number;
+  label: string;
+  status: string;
+  ipv4: string[];
+  ipv6: string;
+  region: string;
+  type: string;
+  created: string;
+  updated: string;
+}
+
+interface LinodeError {
+  errors: Array<{
+    field?: string;
+    reason: string;
+  }>;
+}
+
+export class LinodeProvider extends VPSProviderBase {
+  constructor(apiKey: string, timeout: number = 30000) {
+    super({
+      apiKey,
+      baseUrl: 'https://api.linode.com/v4',
+      timeout,
+    });
+  }
+
+  async createServer(request: CreateServerRequest): Promise<CreateServerResponse> {
+    const url = `${this.config.baseUrl}/linode/instances`;
+
+    const body = {
+      type: request.plan,
+      region: request.region,
+      image: request.osImage,
+      root_pass: request.rootPassword,
+      label: request.label || `server-${Date.now()}`,
+      tags: request.tags || [],
+      authorized_keys: request.sshKeys || [],
+      booted: true,
+    };
+
+    try {
+      const response = await this.fetchWithRetry(url, {
+        method: 'POST',
+        headers: {
+          Authorization: `Bearer ${this.config.apiKey}`,
+          'Content-Type': 'application/json',
+        },
+        body: JSON.stringify(body),
+      });
+
+      if (!response.ok) {
+        const error = (await response.json()) as LinodeError;
+        return {
+          success: false,
+          error: {
+            code: `LINODE_${response.status}`,
+            message: error.errors?.[0]?.reason || 'Unknown error',
+          },
+        };
+      }
+
+      const data = (await response.json()) as LinodeInstance;
+
+      return {
+        success: true,
+        instanceId: String(data.id),
+        ipv4: data.ipv4?.[0],
+        ipv6: data.ipv6?.split('/')[0], // Remove CIDR notation
+        status: data.status,
+      };
+    } catch (error) {
+      return {
+        success: false,
+        error: {
+          code: 'LINODE_NETWORK_ERROR',
+          message: error instanceof Error ? error.message : 'Network error',
+        },
+      };
+    }
+  }
+
+  async deleteServer(instanceId: string): Promise<{ success: boolean; error?: string }> {
+    const url = `${this.config.baseUrl}/linode/instances/${instanceId}`;
+
+    try {
+      const response = await this.fetchWithRetry(url, {
+        method: 'DELETE',
+        headers: {
+          Authorization: `Bearer ${this.config.apiKey}`,
+        },
+      });
+
+      if (!response.ok) {
+        const error = (await response.json()) as LinodeError;
+        return {
+          success: false,
+          error: error.errors?.[0]?.reason || 'Failed to delete instance',
+        };
+      }
+
+      return { success: true };
+    } catch (error) {
+      return {
+        success: false,
+        error: error instanceof Error ? error.message : 'Network error',
+      };
+    }
+  }
+
+  async getServerStatus(
+    instanceId: string
+  ): Promise<{ status: string; ipv4?: string; ipv6?: string }> {
+    const url = `${this.config.baseUrl}/linode/instances/${instanceId}`;
+
+    try {
+      const response = await this.fetchWithRetry(url, {
+        method: 'GET',
+        headers: {
+          Authorization: `Bearer ${this.config.apiKey}`,
+        },
+      });
+
+      if (!response.ok) {
+        return { status: 'unknown' };
+      }
+
+      const data = (await response.json()) as LinodeInstance;
+      return {
+        status: data.status,
+        ipv4: data.ipv4?.[0],
+        ipv6: data.ipv6?.split('/')[0],
+      };
+    } catch {
+      return { status: 'unknown' };
+    }
+  }
+
+  getOsImageId(osImage: string): string {
+    return OS_IMAGE_MAP.linode[osImage as keyof typeof OS_IMAGE_MAP.linode] || 'linode/ubuntu22.04';
+  }
+
+  /**
+   * Generate secure root password for Linode
+   * Linode requires: 6-128 chars, uppercase, lowercase, numeric
+   */
+  generateRootPassword(): string {
+    return this.generateSecurePassword(32);
+  }
+}
--- a/src/services/provisioning-service.ts
+++ b/src/services/provisioning-service.ts
@@ -0,0 +1,392 @@
+/**
+ * Provisioning Service
+ * Orchestrates the server provisioning workflow with Queue-based async processing
+ */
+
+import type { Env, ProvisionRequest, ProvisionResponse, ProvisionQueueMessage, ServerOrder, VPSProvider } from '../types';
+import { ProvisioningRepository } from '../repositories/ProvisioningRepository';
+import { LinodeProvider } from './linode-provider';
+import { VultrProvider } from './vultr-provider';
+import { getExchangeRate } from '../utils/exchange-rate';
+
+export class ProvisioningService {
+  private repo: ProvisioningRepository;
+  private linodeProvider: LinodeProvider | null;
+  private vultrProvider: VultrProvider | null;
+  private env: Env;
+
+  constructor(
+    env: Env,              // Full env for exchange rate API + cache + queue
+    db: D1Database,        // cloud-instances-db: pricing, providers
+    userDb: D1Database,    // telegram-conversations: users, deposits, orders
+    linodeApiKey?: string,
+    vultrApiKey?: string
+  ) {
+    this.env = env;
+    this.repo = new ProvisioningRepository(db, userDb);
+    this.linodeProvider = linodeApiKey ? new LinodeProvider(linodeApiKey) : null;
+    this.vultrProvider = vultrApiKey ? new VultrProvider(vultrApiKey) : null;
+  }
+
+  /**
+   * Main provisioning workflow (async via Queue)
+   * 1. Validate user by telegram_id
+   * 2. Get pricing details
+   * 3. Check and deduct balance (KRW)
+   * 4. Create order with status 'queued'
+   * 5. Send message to Queue
+   * 6. Return immediately with order info
+   */
+  async provisionServer(request: ProvisionRequest): Promise<ProvisionResponse> {
+    const { telegram_id, pricing_id, label, image, dry_run } = request;
+    const osImageKey = image || 'ubuntu_22_04';
+
+    // Step 1: Validate user by telegram_id
+    const user = await this.repo.getUserByTelegramId(telegram_id);
+    if (!user) {
+      return {
+        success: false,
+        error: { code: 'USER_NOT_FOUND', message: 'User not found' },
+      };
+    }
+
+    // Step 2: Get pricing details with provider info
+    const pricing = await this.repo.getPricingWithProvider(pricing_id);
+    if (!pricing) {
+      return {
+        success: false,
+        error: { code: 'PRICING_NOT_FOUND', message: 'Invalid pricing_id or unavailable' },
+      };
+    }
+
+    // Step 3: Calculate price in KRW using real-time exchange rate
+    // Round to nearest 500 KRW for cleaner pricing
+    const exchangeRate = await getExchangeRate(this.env);
+    const priceKrw = Math.round((pricing.monthly_price * exchangeRate) / 500) * 500;
+
+    // Step 4: Check balance
+    const currentBalance = await this.repo.getBalance(user.id);
+    if (currentBalance < priceKrw) {
+      return {
+        success: false,
+        error: {
+          code: 'INSUFFICIENT_BALANCE',
+          message: `Insufficient balance. Required: ₩${priceKrw.toLocaleString()}, Available: ₩${currentBalance.toLocaleString()}`,
+        },
+      };
+    }
+
+    // Dry run mode: return validation result without creating order
+    if (dry_run) {
+      return {
+        success: true,
+        order: {
+          id: 0,
+          user_id: user.id,
+          spec_id: pricing_id,
+          status: 'pending',
+          region: pricing.region_code,
+          provider_instance_id: null,
+          ip_address: null,
+          root_password: null,
+          price_paid: priceKrw,
+          error_message: null,
+          provisioned_at: null,
+          terminated_at: null,
+          created_at: new Date().toISOString(),
+          updated_at: new Date().toISOString(),
+          label: label || null,
+          image: osImageKey,
+          billing_type: 'monthly',
+        },
+        dry_run_info: {
+          message: 'Dry run successful. No server created, no balance deducted.',
+          user_id: user.id,
+          telegram_id,
+          current_balance_krw: currentBalance,
+          price_krw: priceKrw,
+          remaining_balance_krw: currentBalance - priceKrw,
+          provider: pricing.provider_name,
+          instance: pricing.instance_name,
+          region: pricing.region_name,
+        },
+      } as ProvisionResponse;
+    }
+
+    // Step 5: Generate root password before creating order
+    const rootPassword = this.generateSecurePassword();
+
+    // Step 6: Create order with payment (atomic balance deduction + order creation)
+    const orderResult = await this.repo.createOrderWithPayment(
+      user.id,
+      pricing_id,
+      pricing.region_code,
+      priceKrw,
+      label || null,
+      osImageKey
+    );
+
+    if (!orderResult.orderId) {
+      return {
+        success: false,
+        error: {
+          code: orderResult.error || 'ORDER_CREATION_FAILED',
+          message: orderResult.error === 'INSUFFICIENT_BALANCE'
+            ? `Insufficient balance. Required: ₩${priceKrw.toLocaleString()}`
+            : 'Failed to create order',
+        },
+      };
+    }
+
+    const orderId = orderResult.orderId;
+
+    // Step 7: Store root password in order (encrypted in production)
+    await this.repo.updateOrderRootPassword(orderId, rootPassword);
+
+    // Step 8: Update order status to 'queued' and send to Queue
+    await this.repo.updateOrderStatus(orderId, 'provisioning');
+
+    // Send message to provision queue (root_password stored in DB, not in queue for security)
+    const queueMessage: ProvisionQueueMessage = {
+      order_id: orderId,
+      user_id: user.id,
+      pricing_id,
+      label: label || null,
+      image: osImageKey,
+      timestamp: new Date().toISOString(),
+    };
+
+    await this.env.PROVISION_QUEUE.send(queueMessage);
+    console.log(`[ProvisioningService] Order ${orderId} queued for provisioning`);
+
+    // Step 9: Return immediately with order info
+    const order = await this.repo.getOrderById(orderId);
+
+    return {
+      success: true,
+      order: order!,
+    };
+  }
+
+  /**
+   * Process provision queue message (called by Queue consumer)
+   * 1. Get order and pricing details
+   * 2. Call provider API
+   * 3. On success: update order to active
+   * 4. On failure: refund balance, update order to failed
+   */
+  async processQueueMessage(message: ProvisionQueueMessage): Promise<void> {
+    const { order_id, user_id, pricing_id, label, image } = message;
+    console.log(`[ProvisioningService] Processing order ${order_id}`);
+
+    // Fetch order to get root_password (stored in DB for security)
+    const order = await this.repo.getOrderById(order_id);
+    if (!order || !order.root_password) {
+      console.error(`[ProvisioningService] Order or root_password not found for order ${order_id}`);
+      await this.repo.updateOrderStatus(order_id, 'failed', 'Order not found');
+      return;
+    }
+    const root_password = order.root_password;
+
+    // Get pricing details
+    const pricing = await this.repo.getPricingWithProvider(pricing_id);
+    if (!pricing) {
+      console.error(`[ProvisioningService] Pricing not found for order ${order_id}`);
+      await this.repo.rollbackOrder(order_id, user_id, order.price_paid, 'Pricing not found');
+      return;
+    }
+
+    // Get provider
+    const provider = this.getProvider(pricing.provider_name.toLowerCase() as VPSProvider);
+    if (!provider) {
+      console.error(`[ProvisioningService] Provider not configured for order ${order_id}`);
+      await this.repo.rollbackOrder(order_id, user_id, order.price_paid, 'Provider not configured');
+      return;
+    }
+
+    // Get OS image ID
+    const osImageId = provider.getOsImageId(image);
+
+    // Call provider API
+    const createResult = await provider.createServer({
+      plan: pricing.instance_id,
+      region: pricing.region_code,
+      osImage: osImageId,
+      label: label || `order-${order_id}`,
+      rootPassword: root_password,
+      tags: [`user:${user_id}`, `order:${order_id}`],
+    });
+
+    if (!createResult.success) {
+      console.error(`[ProvisioningService] Provider API failed for order ${order_id}:`, createResult.error);
+      await this.repo.rollbackOrder(
+        order_id,
+        user_id,
+        order.price_paid,
+        createResult.error?.message || 'Provider API error'
+      );
+      // Throw error to trigger retry
+      throw new Error(createResult.error?.message || 'Provider API error');
+    }
+
+    // Wait for IP assignment if not immediately available
+    let ipv4 = createResult.ipv4;
+    if (!ipv4 && createResult.instanceId) {
+      console.log(`[ProvisioningService] Waiting for IP assignment for order ${order_id}...`);
+      const readyResult = await this.waitForServerReady(provider, createResult.instanceId);
+      ipv4 = readyResult.ipv4;
+      if (!ipv4) {
+        console.warn(`[ProvisioningService] IP not assigned within timeout for order ${order_id}`);
+      }
+    }
+
+    // Success - update order with provider info
+    await this.repo.updateOrderProviderInfo(
+      order_id,
+      createResult.instanceId!,
+      ipv4 || null,
+      root_password
+    );
+
+    console.log(`[ProvisioningService] Order ${order_id} provisioned successfully: ${createResult.instanceId}, IP: ${ipv4 || 'pending'}`);
+  }
+
+  /**
+   * Get provider instance by name
+   */
+  private getProvider(providerName: VPSProvider): LinodeProvider | VultrProvider | null {
+    switch (providerName) {
+      case 'linode':
+        return this.linodeProvider;
+      case 'vultr':
+        return this.vultrProvider;
+      default:
+        return null;
+    }
+  }
+
+  /**
+   * Wait for server to be ready with IP assigned
+   * Polls getServerStatus every 5 seconds for up to 2 minutes
+   */
+  private async waitForServerReady(
+    provider: LinodeProvider | VultrProvider,
+    instanceId: string,
+    maxWaitMs: number = 120000
+  ): Promise<{ ready: boolean; ipv4?: string; ipv6?: string }> {
+    const startTime = Date.now();
+    const pollInterval = 5000;
+
+    while (Date.now() - startTime < maxWaitMs) {
+      const status = await provider.getServerStatus(instanceId);
+
+      if (status.ipv4) {
+        return { ready: true, ipv4: status.ipv4, ipv6: status.ipv6 };
+      }
+
+      await new Promise((resolve) => setTimeout(resolve, pollInterval));
+    }
+
+    return { ready: false };
+  }
+
+  /**
+   * Generate cryptographically secure password
+   */
+  private generateSecurePassword(length: number = 32): string {
+    const chars = 'ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnpqrstuvwxyz23456789!@#$%^&*';
+    const array = new Uint8Array(length);
+    crypto.getRandomValues(array);
+    let password = '';
+    for (let i = 0; i < length; i++) {
+      password += chars[array[i] % chars.length];
+    }
+    return password;
+  }
+
+  // ============================================
+  // Additional Operations
+  // ============================================
+
+  /**
+   * Get user's server orders by telegram_id
+   */
+  async getUserOrders(telegramId: string, limit: number = 20): Promise<ServerOrder[]> {
+    const user = await this.repo.getUserByTelegramId(telegramId);
+    if (!user) return [];
+    return this.repo.getOrdersByUserId(user.id, limit);
+  }
+
+  /**
+   * Get order by ID
+   */
+  async getOrder(orderId: string): Promise<ServerOrder | null> {
+    const numericId = parseInt(orderId, 10);
+    if (isNaN(numericId)) return null;
+    return this.repo.getOrderById(numericId);
+  }
+
+  /**
+   * Get user balance by telegram_id (in KRW)
+   */
+  async getUserBalance(telegramId: string): Promise<{ balance_krw: number; user_id: number } | null> {
+    const user = await this.repo.getUserByTelegramId(telegramId);
+    if (!user) return null;
+    const balance = await this.repo.getBalance(user.id);
+    return { balance_krw: balance, user_id: user.id };
+  }
+
+  /**
+   * Delete a server (terminate) - requires telegram_id for authorization
+   */
+  async deleteServer(orderId: string, telegramId: string): Promise<{ success: boolean; error?: string }> {
+    const user = await this.repo.getUserByTelegramId(telegramId);
+    if (!user) {
+      return { success: false, error: 'User not found' };
+    }
+
+    const numericOrderId = parseInt(orderId, 10);
+    if (isNaN(numericOrderId)) {
+      return { success: false, error: 'Invalid order ID' };
+    }
+
+    const order = await this.repo.getOrderById(numericOrderId);
+
+    if (!order) {
+      return { success: false, error: 'Order not found' };
+    }
+
+    if (order.user_id !== user.id) {
+      return { success: false, error: 'Unauthorized' };
+    }
+
+    if (order.status !== 'active') {
+      return { success: false, error: 'Server is not active' };
+    }
+
+    if (!order.provider_instance_id) {
+      return { success: false, error: 'No provider instance ID' };
+    }
+
+    // Get provider from pricing info
+    const pricing = await this.repo.getPricingWithProvider(order.spec_id);
+    if (!pricing) {
+      return { success: false, error: 'Pricing info not found' };
+    }
+
+    const provider = this.getProvider(pricing.provider_name.toLowerCase() as VPSProvider);
+    if (!provider) {
+      return { success: false, error: 'Provider not configured' };
+    }
+
+    const deleteResult = await provider.deleteServer(order.provider_instance_id);
+
+    if (!deleteResult.success) {
+      return { success: false, error: deleteResult.error };
+    }
+
+    await this.repo.updateOrderStatus(numericOrderId, 'terminated');
+
+    return { success: true };
+  }
+}
--- a/src/services/vps-provider.ts
+++ b/src/services/vps-provider.ts
@@ -0,0 +1,117 @@
+/**
+ * VPS Provider Abstract Base Class
+ * Common interface for Linode, Vultr, and other VPS providers
+ */
+
+import type { VPSProviderConfig, CreateServerRequest, CreateServerResponse } from '../types';
+
+export abstract class VPSProviderBase {
+  protected config: VPSProviderConfig;
+
+  constructor(config: VPSProviderConfig) {
+    this.config = config;
+  }
+
+  /**
+   * Create a new server instance
+   */
+  abstract createServer(request: CreateServerRequest): Promise<CreateServerResponse>;
+
+  /**
+   * Delete a server instance
+   */
+  abstract deleteServer(instanceId: string): Promise<{ success: boolean; error?: string }>;
+
+  /**
+   * Get server status
+   */
+  abstract getServerStatus(instanceId: string): Promise<{ status: string; ipv4?: string; ipv6?: string }>;
+
+  /**
+   * Map OS image key to provider-specific identifier
+   */
+  abstract getOsImageId(osImage: string): string;
+
+  /**
+   * Fetch with retry and exponential backoff
+   */
+  protected async fetchWithRetry(
+    url: string,
+    options: RequestInit,
+    retries: number = 3
+  ): Promise<Response> {
+    let lastError: Error | null = null;
+
+    for (let i = 0; i < retries; i++) {
+      try {
+        const controller = new AbortController();
+        const timeoutId = setTimeout(() => controller.abort(), this.config.timeout);
+
+        const response = await fetch(url, {
+          ...options,
+          signal: controller.signal,
+        });
+
+        clearTimeout(timeoutId);
+
+        // Don't retry on client errors (4xx), only server errors (5xx)
+        if (response.ok || (response.status >= 400 && response.status < 500)) {
+          return response;
+        }
+
+        // Retry on 5xx errors
+        if (response.status >= 500 && i < retries - 1) {
+          await this.sleep(Math.pow(2, i) * 1000);
+          continue;
+        }
+
+        return response;
+      } catch (error) {
+        lastError = error instanceof Error ? error : new Error(String(error));
+        if (i === retries - 1) break;
+        await this.sleep(Math.pow(2, i) * 1000);
+      }
+    }
+
+    throw lastError ?? new Error('Max retries exceeded');
+  }
+
+  /**
+   * Sleep for specified milliseconds
+   */
+  protected sleep(ms: number): Promise<void> {
+    return new Promise((resolve) => setTimeout(resolve, ms));
+  }
+
+  /**
+   * Generate cryptographically secure password
+   */
+  protected generateSecurePassword(length: number = 32): string {
+    const chars = 'ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnpqrstuvwxyz23456789!@#$%^&*';
+    const array = new Uint8Array(length);
+    crypto.getRandomValues(array);
+    let password = '';
+    for (let i = 0; i < length; i++) {
+      password += chars[array[i] % chars.length];
+    }
+    return password;
+  }
+}
+
+/**
+ * OS Image mapping for providers
+ */
+export const OS_IMAGE_MAP = {
+  linode: {
+    ubuntu_22_04: 'linode/ubuntu22.04',
+    ubuntu_20_04: 'linode/ubuntu20.04',
+    debian_11: 'linode/debian11',
+    debian_12: 'linode/debian12',
+  },
+  vultr: {
+    ubuntu_22_04: '2284',  // Ubuntu 22.04 x64
+    ubuntu_20_04: '1743',  // Ubuntu 20.04 x64
+    debian_11: '477',      // Debian 11 x64
+    debian_12: '2136',     // Debian 12 x64
+  },
+} as const;
--- a/src/services/vultr-provider.ts
+++ b/src/services/vultr-provider.ts
@@ -0,0 +1,189 @@
+/**
+ * Vultr VPS Provider Implementation
+ * API Docs: https://www.vultr.com/api/
+ */
+
+import type { VPSProviderConfig, CreateServerRequest, CreateServerResponse } from '../types';
+import { VPSProviderBase, OS_IMAGE_MAP } from './vps-provider';
+
+interface VultrInstance {
+  id: string;
+  os: string;
+  ram: number;
+  disk: number;
+  main_ip: string;
+  vcpu_count: number;
+  region: string;
+  plan: string;
+  date_created: string;
+  status: string;
+  power_status: string;
+  server_status: string;
+  v6_main_ip: string;
+  v6_network: string;
+  hostname: string;
+  label: string;
+  tag: string;
+}
+
+interface VultrCreateResponse {
+  instance: VultrInstance;
+}
+
+interface VultrError {
+  error: string;
+  status: number;
+}
+
+export class VultrProvider extends VPSProviderBase {
+  constructor(apiKey: string, timeout: number = 30000) {
+    super({
+      apiKey,
+      baseUrl: 'https://api.vultr.com/v2',
+      timeout,
+    });
+  }
+
+  async createServer(request: CreateServerRequest): Promise<CreateServerResponse> {
+    const url = `${this.config.baseUrl}/instances`;
+
+    const body = {
+      plan: request.plan,
+      region: request.region,
+      os_id: parseInt(request.osImage, 10),
+      label: request.label || `server-${Date.now()}`,
+      hostname: request.label || `server-${Date.now()}`,
+      tag: request.tags?.[0] || '',
+      sshkey_id: request.sshKeys || [],
+      enable_ipv6: true,
+      backups: 'disabled',
+      ddos_protection: false,
+    };
+
+    try {
+      const response = await this.fetchWithRetry(url, {
+        method: 'POST',
+        headers: {
+          Authorization: `Bearer ${this.config.apiKey}`,
+          'Content-Type': 'application/json',
+        },
+        body: JSON.stringify(body),
+      });
+
+      if (!response.ok) {
+        const error = (await response.json()) as VultrError;
+        return {
+          success: false,
+          error: {
+            code: `VULTR_${response.status}`,
+            message: error.error || 'Unknown error',
+          },
+        };
+      }
+
+      const data = (await response.json()) as VultrCreateResponse;
+      const instance = data.instance;
+
+      return {
+        success: true,
+        instanceId: instance.id,
+        ipv4: instance.main_ip !== '0.0.0.0' ? instance.main_ip : undefined,
+        ipv6: instance.v6_main_ip || undefined,
+        status: instance.status,
+      };
+    } catch (error) {
+      return {
+        success: false,
+        error: {
+          code: 'VULTR_NETWORK_ERROR',
+          message: error instanceof Error ? error.message : 'Network error',
+        },
+      };
+    }
+  }
+
+  async deleteServer(instanceId: string): Promise<{ success: boolean; error?: string }> {
+    const url = `${this.config.baseUrl}/instances/${instanceId}`;
+
+    try {
+      const response = await this.fetchWithRetry(url, {
+        method: 'DELETE',
+        headers: {
+          Authorization: `Bearer ${this.config.apiKey}`,
+        },
+      });
+
+      // Vultr returns 204 No Content on success
+      if (response.status === 204 || response.ok) {
+        return { success: true };
+      }
+
+      const error = (await response.json()) as VultrError;
+      return {
+        success: false,
+        error: error.error || 'Failed to delete instance',
+      };
+    } catch (error) {
+      return {
+        success: false,
+        error: error instanceof Error ? error.message : 'Network error',
+      };
+    }
+  }
+
+  async getServerStatus(
+    instanceId: string
+  ): Promise<{ status: string; ipv4?: string; ipv6?: string }> {
+    const url = `${this.config.baseUrl}/instances/${instanceId}`;
+
+    try {
+      const response = await this.fetchWithRetry(url, {
+        method: 'GET',
+        headers: {
+          Authorization: `Bearer ${this.config.apiKey}`,
+        },
+      });
+
+      if (!response.ok) {
+        return { status: 'unknown' };
+      }
+
+      const data = (await response.json()) as { instance: VultrInstance };
+      return {
+        status: data.instance.status,
+        ipv4: data.instance.main_ip !== '0.0.0.0' ? data.instance.main_ip : undefined,
+        ipv6: data.instance.v6_main_ip || undefined,
+      };
+    } catch {
+      return { status: 'unknown' };
+    }
+  }
+
+  getOsImageId(osImage: string): string {
+    return OS_IMAGE_MAP.vultr[osImage as keyof typeof OS_IMAGE_MAP.vultr] || '2284'; // Default Ubuntu 22.04
+  }
+
+  /**
+   * Wait for server to be ready (IP assigned)
+   * Vultr servers may take a minute to get IP addresses
+   */
+  async waitForReady(
+    instanceId: string,
+    maxWaitMs: number = 120000
+  ): Promise<{ ready: boolean; ipv4?: string; ipv6?: string }> {
+    const startTime = Date.now();
+    const pollInterval = 5000;
+
+    while (Date.now() - startTime < maxWaitMs) {
+      const status = await this.getServerStatus(instanceId);
+
+      if (status.status === 'active' && status.ipv4) {
+        return { ready: true, ipv4: status.ipv4, ipv6: status.ipv6 };
+      }
+
+      await this.sleep(pollInterval);
+    }
+
+    return { ready: false };
+  }
+}
--- a/src/types.ts
+++ b/src/types.ts
@@ -4,10 +4,29 @@

 export interface Env {
  AI: Ai;  // Legacy - kept for fallback
-  DB: D1Database;
+  DB: D1Database;              // cloud-instances-db: server specs, pricing
+  USER_DB: D1Database;         // telegram-conversations: users, deposits, orders
  CACHE: KVNamespace;
  OPENAI_API_KEY: string;
  AI_GATEWAY_URL?: string;  // Cloudflare AI Gateway URL to bypass regional restrictions
+  // VPS Provider API Keys
+  LINODE_API_KEY?: string;
+  VULTR_API_KEY?: string;
+  // Provision API security
+  PROVISION_API_KEY?: string;  // Required for /api/provision/* endpoints
+  // Queue for async provisioning
+  PROVISION_QUEUE: Queue<ProvisionQueueMessage>;
+}
+
+// Queue message for async server provisioning
+// Note: root_password is stored in DB, not in queue message for security
+export interface ProvisionQueueMessage {
+  order_id: number;
+  user_id: number;
+  pricing_id: number;
+  label: string | null;
+  image: string;
+  timestamp: string;
 }

 export interface ValidationError {
@@ -203,3 +222,110 @@ export interface AIRecommendationResponse {
  }>;
  infrastructure_tips?: string[];
 }
+
+// ============================================
+// Provisioning System Types (telegram-conversations DB)
+// ============================================
+
+// users table
+export interface TelegramUser {
+  id: number;                    // AUTO INCREMENT
+  telegram_id: string;           // Telegram user ID (used as external identifier)
+  username: string | null;
+  first_name: string | null;
+  created_at: string;
+  updated_at: string;
+}
+
+// user_deposits table (balance in KRW, INTEGER)
+export interface UserDeposit {
+  id: number;
+  user_id: number;               // References users.id
+  balance: number;               // Balance in KRW (원)
+  created_at: string;
+  updated_at: string;
+}
+
+// server_orders table (existing schema)
+export interface ServerOrder {
+  id: number;                    // AUTO INCREMENT
+  user_id: number;               // References users.id
+  spec_id: number;               // Server spec ID
+  status: 'pending' | 'provisioning' | 'active' | 'failed' | 'cancelled' | 'terminated';
+  region: string;
+  provider_instance_id: string | null;
+  ip_address: string | null;
+  root_password: string | null;
+  price_paid: number;            // Price in KRW (원)
+  error_message: string | null;
+  provisioned_at: string | null;
+  terminated_at: string | null;
+  created_at: string;
+  updated_at: string;
+  label: string | null;
+  image: string | null;
+  billing_type: string;          // 'monthly' default
+}
+
+export type VPSProvider = 'linode' | 'vultr';
+
+export interface ProvisionRequest {
+  telegram_id: string;           // Telegram user ID
+  pricing_id: number;            // From cloud-instances-db.pricing
+  label?: string;
+  image?: string;                // OS image (e.g., 'ubuntu_22_04')
+  dry_run?: boolean;             // Test mode: validate only, don't create server
+}
+
+export interface ProvisionResponse {
+  success: boolean;
+  order?: ServerOrder;
+  error?: {
+    code: string;
+    message: string;
+  };
+}
+
+// Provider API types
+export interface VPSProviderConfig {
+  apiKey: string;
+  baseUrl: string;
+  timeout: number;
+}
+
+export interface CreateServerRequest {
+  plan: string;           // Provider-specific plan ID (instance_id)
+  region: string;         // Provider-specific region code
+  osImage: string;        // OS identifier
+  label?: string;
+  rootPassword: string;
+  sshKeys?: string[];
+  tags?: string[];
+}
+
+export interface CreateServerResponse {
+  success: boolean;
+  instanceId?: string;
+  ipv4?: string;
+  ipv6?: string;
+  status?: string;
+  error?: {
+    code: string;
+    message: string;
+  };
+}
+
+export interface PricingWithProvider {
+  pricing_id: number;
+  provider_id: number;
+  provider_name: string;
+  api_base_url: string;
+  instance_id: string;       // Provider's plan ID (e.g., g6-nanode-1)
+  instance_name: string;
+  region_code: string;       // Provider's region code
+  region_name: string;
+  monthly_price: number;
+  vcpu: number;
+  memory_mb: number;
+  storage_gb: number;
+}
--- a/src/utils/http.ts
+++ b/src/utils/http.ts
@@ -36,6 +36,36 @@ export function jsonResponse<T>(
  });
 }

+/**
+ * Create error response
+ */
+export function createErrorResponse(
+  message: string,
+  status: number,
+  code?: string,
+  corsHeaders: Record<string, string> = {}
+): Response {
+  return jsonResponse(
+    {
+      error: message,
+      code: code || 'ERROR',
+    },
+    status,
+    corsHeaders
+  );
+}
+
+/**
+ * Create success response
+ */
+export function createSuccessResponse<T>(
+  data: T,
+  status: number = 200,
+  corsHeaders: Record<string, string> = {}
+): Response {
+  return jsonResponse(data, status, corsHeaders);
+}
+
 /**
 * Helper function to get allowed CORS origin
 */
@@ -61,3 +91,34 @@ export function getAllowedOrigin(request: Request): string {
  // Browser will block the response due to CORS mismatch
  return allowedOrigins[0];
 }
+
+/**
+ * Validate request origin for sensitive endpoints (e.g., provision)
+ * Only allows requests from *.kappa-d8e.workers.dev or worker-to-worker calls
+ */
+export function isAllowedProvisionOrigin(request: Request): boolean {
+  const origin = request.headers.get('Origin');
+  const referer = request.headers.get('Referer');
+
+  // Allow worker-to-worker calls (Cloudflare adds this header)
+  // Note: This header indicates the request came from another Cloudflare Worker
+  const cfWorker = request.headers.get('CF-Worker');
+  if (cfWorker) {
+    return true;
+  }
+
+  // If no Origin header (server-to-server, curl, etc.) - check Referer or allow
+  // For strict mode, you might want to reject these too
+  if (!origin) {
+    // Check Referer as fallback
+    if (referer && referer.includes('.kappa-d8e.workers.dev')) {
+      return true;
+    }
+    // Allow server-to-server for now (can be made stricter with API key)
+    return true;
+  }
+
+  // Check if Origin is from allowed domain
+  const allowedPattern = /^https:\/\/[a-zA-Z0-9-]+\.kappa-d8e\.workers\.dev$/;
+  return allowedPattern.test(origin);
+}
--- a/src/utils/index.ts
+++ b/src/utils/index.ts
@@ -7,7 +7,8 @@
 export {
  escapeHtml,
  jsonResponse,
-  getAllowedOrigin
+  getAllowedOrigin,
+  isAllowedProvisionOrigin
 } from './http';

 // Validation utilities (type guards, request validation)