Feature/lambda origins

package.json

@@ -8,19 +8,19 @@
   "license": "BSD-3",
   "private": true,
   "scripts": {
-    "build": "webpack; zip -j dist/lambda-gateway.zip dist/*; rm dist/index.js"
+    "build": "rm -rf dist; mkdir -p dist; webpack; zip -j dist/lambda-gateway.zip dist/*; rm dist/index.js"
   },
   "dependencies": {
-    "aws-sdk": "^2.1117.0"
+    "aws-sdk": "^2.1153.0"
   },
   "devDependencies": {
-    "@types/aws-lambda": "^8.10.94",
+    "@types/aws-lambda": "^8.10.100",
     "@types/node": "^17.0.25",
-    "fork-ts-checker-webpack-plugin": "^7.2.6",
-    "ts-loader": "^9.2.6",
-    "ts-node": "^10.7.0",
-    "typescript": "^4.6.3",
-    "webpack": "^5.61.0",
-    "webpack-cli": "^4.9.1"
+    "fork-ts-checker-webpack-plugin": "^7.2.11",
+    "ts-loader": "^9.3.0",
+    "ts-node": "^10.8.1",
+    "typescript": "^4.7.3",
+    "webpack": "^5.73.0",
+    "webpack-cli": "^4.10.0"
   }
 }

src/index.ts

@@ -1,16 +1,17 @@
 import path from 'path';
+import { urlToHttpOptions } from 'url';
 import { CloudFrontRequestEvent, CloudFrontRequestResult } from 'aws-lambda';
 
-function log(message: string, context: any) {
-  console.log(
-    JSON.stringify({
-      message,
-      context,
-    })
-  );
-}
-
 export async function handler(event: CloudFrontRequestEvent): Promise<CloudFrontRequestResult> {
+  const log = (message: string, context: any) => {
+    console.info(
+      JSON.stringify({
+        message,
+        context,
+      })
+    );
+  };
+
   try {
     const { config, request } = event.Records[0].cf;
     if (config.eventType.toLowerCase() !== 'origin-request') {
@@ -25,13 +26,38 @@ export async function handler(event: CloudFrontRequestEvent): Promise<CloudFront
     const baseHost = s3.customHeaders['x-base-host'][0].value;
     const hostDiff = targetHost.length - baseHost.length;
     const subDomain = hostDiff > 0 ? targetHost.substring(0, hostDiff - 1) : 'www';
-    const s3Path = path.join(s3.path, subDomain);
+    const s3Path = path.join(s3.path, subDomain).replace(/\/$/i, '');
 
-    log('Redirecting request to origin path', { s3Path, request });
+    const customHost =
+      s3.customHeaders[`x-origin-${subDomain.toLowerCase()}`]?.[0]?.value ??
+      s3.customHeaders[`X-Origin-${subDomain.toUpperCase()}`]?.[0]?.value ??
+      null;
+    if (!!customHost) {
+      const opts = urlToHttpOptions(new URL(customHost));
+      log('Redirecting request to custom origin', { s3Path, request, opts });
+      Reflect.deleteProperty(request.origin, 's3');
+      const uri = opts.path.split('/').pop();
+      request.origin.custom = {
+        path: opts.path.split('/').reverse().splice(1).reverse().join('/'),
+        readTimeout: 30,
+        keepaliveTimeout: 5,
+        domainName: opts.hostname,
+        customHeaders: s3.customHeaders,
+        port: parseInt(`${opts.port ?? '443'}`),
+        sslProtocols: ['TLSv1', 'TLSv1.1', 'TLSv1.2'],
+        protocol: 'https',
+      };
+      request.uri = `/${uri}`;
+      request.headers['host'][0].value = opts.hostname;
+    } else {
+      log('Redirecting request to S3 origin path', { s3Path, request });
+
+      request.origin.s3.path = s3Path;
+      request.headers['host'][0].value = request.origin.s3.domainName;
+    }
 
-    request.origin.s3.path = s3Path;
-    request.headers['host'][0].value = request.origin.s3.domainName;
     request.headers['x-target-domain'] = [{ value: targetHost }];
+    log('Responding with modified request', { request });
 
     return request;
   } catch (e) {