feat: proxy preview content

src/controllers/proxy.js

@@ -0,0 +1,316 @@
+/*
+ * Copyright 2025 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+/* c8 ignore start */
+import {
+  badRequest,
+  createResponse,
+  internalServerError,
+  notFound,
+} from '@adobe/spacecat-shared-http-utils';
+import { hasText, tracingFetch as fetch } from '@adobe/spacecat-shared-utils';
+import { getImsUserToken } from '../support/utils.js';
+
+/**
+ * Decodes a base64-encoded URL.
+ * @param {string} base64Url - The base64-encoded URL.
+ * @returns {string} The decoded URL.
+ * @throws {Error} If the URL cannot be decoded.
+ */
+function decodeBase64Url(base64Url) {
+  try {
+    return Buffer.from(base64Url, 'base64').toString('utf-8');
+  } catch (error) {
+    throw new Error(`Failed to decode base64 URL: ${error.message}`);
+  }
+}
+
+/**
+ * Encodes a URL to base64.
+ * @param {string} url - The URL to encode.
+ * @returns {string} The base64-encoded URL.
+ */
+function encodeUrlToBase64(url) {
+  return Buffer.from(url, 'utf-8').toString('base64');
+}
+
+/**
+ * Fetches HTML content from the target URL using the IMS bearer token.
+ * @param {string} targetUrl - The URL to fetch.
+ * @param {string} bearerToken - The IMS bearer token for authentication.
+ * @param {object} log - The logger instance.
+ * @returns {Promise<{html: string, contentType: string}>} The HTML content and content type.
+ * @throws {Error} If the fetch fails.
+ */
+async function fetchHtmlContent(targetUrl, bearerToken, log) {
+  try {
+    log.info(`Fetching content from: ${targetUrl}`);
+    const response = await fetch(targetUrl, {
+      method: 'GET',
+      headers: {
+        Authorization: `Bearer ${bearerToken}`,
+      },
+    });
+
+    if (!response.ok) {
+      throw new Error(`HTTP ${response.status}: ${response.statusText}`);
+    }
+
+    const contentType = response.headers.get('content-type') || 'text/html';
+    const html = await response.text();
+
+    log.info(`Successfully fetched ${html.length} bytes from ${targetUrl}`);
+    return { html, contentType };
+  } catch (error) {
+    log.error(`Failed to fetch content from ${targetUrl}:`, error);
+    throw error;
+  }
+}
+
+/**
+ * Resolves a potentially relative URL to an absolute URL.
+ * @param {string} url - The URL to resolve.
+ * @param {string} base - The base URL.
+ * @returns {string|null} The absolute URL, or null if invalid.
+ */
+function resolveUrl(url, base) {
+  try {
+    // If URL is already absolute, return it
+    if (url.startsWith('http://') || url.startsWith('https://')) {
+      return url;
+    }
+    // If URL starts with //, it's protocol-relative
+    if (url.startsWith('//')) {
+      return `https:${url}`;
+    }
+    // If URL starts with /, it's relative to origin
+    if (url.startsWith('/')) {
+      return `${base}${url}`;
+    }
+    // Otherwise, try to resolve it as a relative URL
+    return new URL(url, base).href;
+  } catch (error) {
+    return null;
+  }
+}
+
+/**
+ * Determines if a URL should be proxied.
+ * @param {string} url - The URL to check.
+ * @param {string} origin - The origin of the page being proxied.
+ * @returns {boolean} True if the URL should be proxied.
+ */
+function shouldProxyUrl(url, origin) {
+  try {
+    const urlObj = new URL(url);
+    // Only proxy URLs from the same origin
+    return urlObj.origin === origin;
+  } catch (error) {
+    return false;
+  }
+}
+
+/**
+ * Rewrites image URLs in the HTML to proxy them through the SpaceCat API.
+ * @param {string} html - The HTML content.
+ * @param {string} baseUrl - The base URL of the original page.
+ * @param {string} siteId - The site ID for the proxy route.
+ * @param {string} apiBaseUrl - The SpaceCat API base URL.
+ * @param {object} log - The logger instance.
+ * @returns {string} The HTML with rewritten image URLs.
+ */
+function rewriteImageUrls(html, baseUrl, siteId, apiBaseUrl, log) {
+  try {
+    const urlObj = new URL(baseUrl);
+    const { origin } = urlObj;
+    log.info(`Rewriting image URLs with base: ${origin}, for siteId: ${siteId}, apiBaseUrl: ${apiBaseUrl}`);
+
+    // Pattern to match img src attributes
+    // Matches: <img src="..." or <img ... src="..."
+    let rewrittenHtml = html;
+    let rewriteCount = 0;
+
+    // Rewrite img src attributes
+    rewrittenHtml = rewrittenHtml.replace(
+      /<img([^>]*?)src=["']([^"']+)["']/gi,
+      (match, beforeSrc, srcUrl) => {
+        const absoluteUrl = resolveUrl(srcUrl, origin);
+        if (absoluteUrl && shouldProxyUrl(absoluteUrl, origin)) {
+          const base64Url = encodeUrlToBase64(absoluteUrl);
+          const proxyUrl = `${apiBaseUrl}/sites/${siteId}/csproxy/${base64Url}`;
+          rewriteCount += 1;
+          return `<img${beforeSrc}src="${proxyUrl}"`;
+        }
+        return match;
+      },
+    );
+
+    // Rewrite CSS background-image URLs
+    rewrittenHtml = rewrittenHtml.replace(
+      /background-image:\s*url\(["']?([^"')]+)["']?\)/gi,
+      (match, bgUrl) => {
+        const absoluteUrl = resolveUrl(bgUrl, origin);
+        if (absoluteUrl && shouldProxyUrl(absoluteUrl, origin)) {
+          const base64Url = encodeUrlToBase64(absoluteUrl);
+          const proxyUrl = `${apiBaseUrl}/sites/${siteId}/csproxy/${base64Url}`;
+          rewriteCount += 1;
+          return `background-image: url("${proxyUrl}")`;
+        }
+        return match;
+      },
+    );
+
+    // Rewrite picture source srcset attributes
+    rewrittenHtml = rewrittenHtml.replace(
+      /<source([^>]*?)srcset=["']([^"']+)["']/gi,
+      (match, beforeSrcset, srcsetValue) => {
+        const rewrittenSrcset = srcsetValue.split(',').map((srcsetItem) => {
+          const [url, descriptor] = srcsetItem.trim().split(/\s+/);
+          const absoluteUrl = resolveUrl(url, origin);
+          if (absoluteUrl && shouldProxyUrl(absoluteUrl, origin)) {
+            const base64Url = encodeUrlToBase64(absoluteUrl);
+            const proxyUrl = `${apiBaseUrl}/sites/${siteId}/csproxy/${base64Url}`;
+            rewriteCount += 1;
+            return descriptor ? `${proxyUrl} ${descriptor}` : proxyUrl;
+          }
+          return srcsetItem.trim();
+        }).join(', ');
+        return `<source${beforeSrcset}srcset="${rewrittenSrcset}"`;
+      },
+    );
+
+    // Rewrite img srcset attributes
+    rewrittenHtml = rewrittenHtml.replace(
+      /<img([^>]*?)srcset=["']([^"']+)["']/gi,
+      (match, beforeSrcset, srcsetValue) => {
+        const rewrittenSrcset = srcsetValue.split(',').map((srcsetItem) => {
+          const [url, descriptor] = srcsetItem.trim().split(/\s+/);
+          const absoluteUrl = resolveUrl(url, origin);
+          if (absoluteUrl && shouldProxyUrl(absoluteUrl, origin)) {
+            const base64Url = encodeUrlToBase64(absoluteUrl);
+            const proxyUrl = `${apiBaseUrl}/sites/${siteId}/csproxy/${base64Url}`;
+            rewriteCount += 1;
+            return descriptor ? `${proxyUrl} ${descriptor}` : proxyUrl;
+          }
+          return srcsetItem.trim();
+        }).join(', ');
+        return `<img${beforeSrcset}srcset="${rewrittenSrcset}"`;
+      },
+    );
+
+    log.info(`Rewrote ${rewriteCount} image URLs`);
+    return rewrittenHtml;
+  } catch (error) {
+    log.error('Failed to rewrite image URLs:', error);
+    return html; // Return original HTML if rewrite fails
+  }
+}
+
+/**
+ * Proxy controller. Provides a method to proxy content from authenticated AEM instances.
+ * @param {object} ctx - Context of the request.
+ * @param {object} log - Logger instance.
+ * @returns {object} Proxy controller.
+ */
+function ProxyController(ctx, log) {
+  // Hardcoded to 'ci' for now
+  const apiBaseUrl = 'https://spacecat.experiencecloud.live/api/ci';
+  /**
+   * Proxies content from the base64-encoded URL.
+   * GET /sites/:siteId/csproxy/:base64ProxyUrl
+   * @param {object} context - The request context.
+   * @returns {Promise<object>} The response with proxied content.
+   */
+  async function proxyContent(context) {
+    const base64ProxyUrl = context.params?.base64ProxyUrl;
+    const siteId = context.params?.siteId;
+
+    // Validate siteId
+    if (!hasText(siteId)) {
+      return badRequest('Site ID is required');
+    }
+
+    // Validate base64ProxyUrl
+    if (!hasText(base64ProxyUrl)) {
+      return badRequest('Proxy URL is required');
+    }
+
+    try {
+      // Decode the base64 URL
+      const targetUrl = decodeBase64Url(base64ProxyUrl);
+      log.info(`Proxy request for siteId: ${siteId}, targetUrl: ${targetUrl}`);
+
+      // Validate decoded URL
+      if (!targetUrl.startsWith('http://') && !targetUrl.startsWith('https://')) {
+        return badRequest('Invalid URL format');
+      }
+
+      // Get IMS bearer token from request headers
+      let bearerToken;
+      try {
+        bearerToken = getImsUserToken(context);
+      } catch (error) {
+        log.error('Failed to get IMS token:', error);
+        return badRequest('Missing or invalid Authorization header');
+      }
+
+      // Fetch content from target URL
+      const { html, contentType } = await fetchHtmlContent(targetUrl, bearerToken, log);
+
+      // Check if content is HTML (should rewrite URLs)
+      const isHtml = contentType.includes('text/html') || contentType.includes('application/xhtml+xml');
+
+      if (isHtml) {
+        // Rewrite image URLs in HTML
+        // Note: CSS/JS URLs are NOT rewritten - they load directly from AEM CS
+        const rewrittenHtml = rewriteImageUrls(html, targetUrl, siteId, apiBaseUrl, log);
+
+        return createResponse(rewrittenHtml, 200, {
+          'Content-Type': contentType,
+          'Cache-Control': 'no-cache, no-store, must-revalidate',
+          'X-Proxy-Source': targetUrl,
+        });
+      }
+
+      // For non-HTML content (images, etc.), return as-is
+      return createResponse(html, 200, {
+        'Content-Type': contentType,
+        'Cache-Control': 'public, max-age=3600',
+        'X-Proxy-Source': targetUrl,
+      });
+    } catch (error) {
+      log.error('Proxy request failed:', error);
+
+      if (error.message.includes('decode')) {
+        return badRequest(`Invalid base64 URL: ${error.message}`);
+      }
+
+      if (error.message.includes('HTTP 404')) {
+        return notFound('Resource not found at target URL');
+      }
+
+      if (error.message.includes('HTTP 401') || error.message.includes('HTTP 403')) {
+        return createResponse('Unauthorized or forbidden', 403, {
+          'Content-Type': 'text/plain',
+        });
+      }
+
+      return internalServerError(`Failed to proxy content: ${error.message}`);
+    }
+  }
+
+  return {
+    proxyContent,
+  };
+}
+
+export default ProxyController;
+/* c8 ignore end */

src/index.js

@@ -75,6 +75,7 @@ import TrialUsersController from './controllers/trial-users.js';
 import EntitlementsController from './controllers/entitlements.js';
 import SandboxAuditController from './controllers/sandbox-audit.js';
 import PTA2Controller from './controllers/paid/pta2.js';
+import ProxyController from './controllers/proxy.js';
 
 const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
 
@@ -139,6 +140,7 @@ async function run(request, context) {
     const entitlementsController = EntitlementsController(context);
     const sandboxAuditController = SandboxAuditController(context);
     const pta2Controller = PTA2Controller(context, log, context.env);
+    const proxyController = ProxyController(context, log);
 
     const routeHandlers = getRouteHandlers(
       auditsController,
@@ -173,6 +175,7 @@ async function run(request, context) {
       sandboxAuditController,
       reportsController,
       pta2Controller,
+      proxyController,
     );
 
     const routeMatch = matchPath(method, suffix, routeHandlers);

src/routes/index.js

@@ -79,6 +79,7 @@ function isStaticRoute(routePattern) {
  * @param {Object} sandboxAuditController - The sandbox audit controller.
  * @param {Object} reportsController - The reports controller.
  * @param {Object} pta2Controller - The PTA2 controller.
+ * @param {Object} proxyController - The proxy controller.
  * @return {{staticRoutes: {}, dynamicRoutes: {}}} - An object with static and dynamic routes.
  */
 export default function getRouteHandlers(
@@ -114,6 +115,7 @@ export default function getRouteHandlers(
   sandboxAuditController,
   reportsController,
   pta2Controller,
+  proxyController,
 ) {
   const staticRoutes = {};
   const dynamicRoutes = {};
@@ -252,6 +254,7 @@ export default function getRouteHandlers(
     'GET /sites/:siteId/top-pages': sitesController.getTopPages,
     'GET /sites/:siteId/top-pages/:source': sitesController.getTopPages,
     'GET /sites/:siteId/top-pages/:source/:geo': sitesController.getTopPages,
+    'GET /sites/:siteId/csproxy/:base64ProxyUrl': proxyController.proxyContent,
     'GET /slack/events': slackController.handleEvent,
     'POST /slack/events': slackController.handleEvent,
     'POST /slack/channels/invite-by-user-id': slackController.inviteUserToChannel,

test/routes/index.test.js

@@ -263,6 +263,10 @@ describe('getRouteHandlers', () => {
     deleteReport: sinon.stub(),
   };
 
+  const mockProxyController = {
+    proxyContent: sinon.stub(),
+  };
+
   it('segregates static and dynamic routes', () => {
     const { staticRoutes, dynamicRoutes } = getRouteHandlers(
       mockAuditsController,
@@ -297,6 +301,7 @@ describe('getRouteHandlers', () => {
       mockSandboxAuditController,
       mockReportsController,
       mockPTA2Controller,
+      mockProxyController,
     );
 
     expect(staticRoutes).to.have.all.keys(
@@ -411,6 +416,7 @@ describe('getRouteHandlers', () => {
       'GET /sites/:siteId/brand-guidelines',
       'GET /sites/:siteId/brand-profile',
       'POST /sites/:siteId/brand-profile',
+      'GET /sites/:siteId/csproxy/:base64ProxyUrl',
       'GET /sites/:siteId/opportunities',
       'GET /sites/:siteId/opportunities/by-status/:status',
       'GET /sites/:siteId/opportunities/:opportunityId',