Function fetch

services/app-builder/src/index.ts:91–198

(request: Request, env: Env, ctx: ExecutionContext)

      const pathname = url.pathname;

      const subdomainAppId = extractAppIdFromSubdomain(url.hostname, env.BUILDER_HOSTNAME);
      const pathAppId = extractAppIdFromPath(pathname);
      const appId = subdomainAppId ?? pathAppId;

      if (appId) {
        logger.setTags({ appId });
      }

      logger.info('Request received', {
        method: request.method,
        pathname,
      });

      if (subdomainAppId) {
        const allowedOrigin = getAllowedOrigin(request, env);

        // Handle CORS preflight for cross-origin requests (e.g. keep-alive pings from app.kilo.ai)
        if (allowedOrigin && request.method === 'OPTIONS') {
          const preflight = withCorsHeaders(new Response(null, { status: 204 }), allowedOrigin);
          preflight.headers.set('Access-Control-Max-Age', '86400');
          return preflight;
        }

        // All requests to app-id.* subdomain are proxied to the preview sandbox
        const response = await handlePreviewProxy(request, env, subdomainAppId);
        return allowedOrigin ? withCorsHeaders(response, allowedOrigin) : response;
      }

      const initMatch = pathname.match(INIT_PATTERN);
      if (initMatch && request.method === 'POST') {
        return handleInit(request, env, initMatch[1]);
      }

      const tokenMatch = pathname.match(TOKEN_PATTERN);
      if (tokenMatch && request.method === 'POST') {
        return handleGenerateToken(request, env, tokenMatch[1]);
      }

      const commitMatch = pathname.match(COMMIT_PATTERN);
      if (commitMatch && request.method === 'GET') {
        return handleGetCommit(request, env, commitMatch[1]);
      }

      const previewStatusMatch = pathname.match(PREVIEW_STATUS_PATTERN);
      if (previewStatusMatch && request.method === 'GET') {
        const matchedAppId = previewStatusMatch[1];
        if (env.DEV_MODE) {
          previewAppId = matchedAppId;
        }
        return handleGetPreviewStatus(request, env, matchedAppId);
      }

      const buildTriggerMatch = pathname.match(BUILD_TRIGGER_PATTERN);
      if (buildTriggerMatch && request.method === 'POST') {
        return handleTriggerBuild(request, env, buildTriggerMatch[1]);
      }

      const buildLogsMatch = pathname.match(BUILD_LOGS_PATTERN);