Convert fn to ts and unit test

.github/workflows/build-and-deploy.yml

@@ -43,5 +43,8 @@ jobs:
       - name: install node dependencies 🔨
         run: cd cdk && npm install
 
+      - name: build and test the cdk solution 🧪
+        run: cd cdk && npm run build && npm run test
+
       - name: deploy it all! 🙈
         run: cd cdk && npm run cdk deploy

cdk/.gitignore

@@ -6,6 +6,3 @@ node_modules
 # CDK asset staging directory
 .cdk.staging
 cdk.out
-
-# Allow cloudfront distribution function to be picked up
-!/cfd-fn/*.js

cdk/cfd-fn/url-rewrite.js → cdk/cfd-fn/url-rewrite.ts

@@ -1,9 +1,7 @@
-// url-rewrite.js
-// See other AWS examples at https://github.com/aws-samples/amazon-cloudfront-functions/)
-
-function handler(event) {
-    var request = event.request;
-    var uri = request.uri;
+const handler = (event: AWSCloudFrontFunction.Event): AWSCloudFrontFunction.Request =>
+{
+    const { request } = event;
+    const { uri } = request;
 
     // Check whether the URI is missing a file name.
     if (uri.endsWith('/')) {
@@ -13,6 +11,8 @@ function handler(event) {
     else if (!uri.includes('.')) {
         request.uri += '/index.html';
     }
-    
+
     return request;
-}
+};
+
+export default handler;

cdk/package.json

@@ -15,13 +15,14 @@
     "@types/jest": "^27.5.2",
     "@types/node": "10.17.27",
     "@types/prettier": "2.6.0",
+    "aws-cdk": "2.53.0",
     "jest": "^27.5.1",
     "ts-jest": "^27.1.4",
-    "aws-cdk": "2.53.0",
     "ts-node": "^10.9.1",
     "typescript": "~3.9.7"
   },
   "dependencies": {
+    "@types/aws-cloudfront-function": "^1.0.2",
     "aws-cdk-lib": "2.53.0",
     "constructs": "^10.0.0",
     "source-map-support": "^0.5.21"

cdk/test/cfd-fn/url-rewrite.test.ts

@@ -0,0 +1,90 @@
+import handler from '../../cfd-fn/url-rewrite';
+
+const cffValue: AWSCloudFrontFunction.ValueObject = {
+    key1: { value: 'text/plain' },
+};
+
+const cffResponseCookie: AWSCloudFrontFunction.ResponseCookie = {
+    id: {
+        value: 'text/plain',
+        attributes: "Expires=Wed, 05 Apr 2021 07:28:00 GMT",
+    },
+    cookie1: {
+        value: 'val1',
+        attributes: "Secure; Domain=example.com; Expires=Wed, 05 Apr 2021 07:28:00 GMT",
+        multiValue: [
+            {
+                value: 'val1',
+                attributes: "Secure; Domain=example.com; Expires=Wed, 05 Apr 2021 07:28:00 GMT",
+            },
+            {
+                value: "val2",
+                attributes: "Path=/cat; Domain=example.com; Expires=Wed, 10 Jan 2021 07:28:00 GMT",
+            }
+        ]
+    },
+};
+
+const cffResponse: AWSCloudFrontFunction.Response = {
+    statusCode: 200,
+    statusDescription: 'OK',
+    headers: cffValue,
+    cookies: cffResponseCookie,
+};
+
+const cffViewer: AWSCloudFrontFunction.Viewer = {
+    ip: '192.168.0.1',
+};
+
+const cffContext: AWSCloudFrontFunction.Context = {
+    distributionDomainName: 'd111111abcdef8.cloudfront.net',
+    distributionId: 'EDFDVBD6EXAMPLE',
+    eventType: 'viewer-response',
+    requestId: 'EXAMPLEntjQpEXAMPLE_SG5Z-EXAMPLEPmPfEXAMPLEu3EqEXAMPLE==',
+};
+
+function BuildEvent(uri: string) : AWSCloudFrontFunction.Event {
+    const cffRequest: AWSCloudFrontFunction.Request = {
+        method: 'GET',
+        uri: uri,
+        querystring: cffValue,
+        headers: cffValue,
+        cookies: cffValue
+    };
+
+    return {
+        version: '1.0',
+        context: cffContext,
+        viewer: cffViewer,
+        request: cffRequest,
+        response: cffResponse,
+    };
+}
+
+describe('testing the CloudFront Function', () => {
+
+    test('when the uri ends in / then index.html should be appended', () => {
+        const event = BuildEvent('/test/');
+        const returnedRequest = handler(event);
+
+        expect(returnedRequest).toBe(event.request);
+        expect(returnedRequest.uri).toBe('/test/index.html');
+    });
+
+    test('when the uri does not contain . then  /index.html should be appended', () => {
+        const event = BuildEvent('/test');
+        const returnedRequest = handler(event);
+
+        expect(returnedRequest).toBe(event.request);
+        expect(returnedRequest.uri).toBe('/test/index.html');
+    });
+
+    test('when the uri has a file extension it should be unaltered', () => {
+        const event = BuildEvent('/test/file.png');
+        const returnedRequest = handler(event);
+
+        expect(returnedRequest).toBe(event.request);
+        expect(returnedRequest.uri).toBe('/test/file.png');
+    });
+
+});

cdk/tsconfig-ignore.json

@@ -0,0 +1,31 @@
+{
+    "compilerOptions": {
+      "target": "ES5",
+      "module": "commonjs",
+      "lib": [
+        "ES2015"
+      ],
+      "declaration": true,
+      "strict": true,
+      "noImplicitAny": true,
+      "strictNullChecks": true,
+      "noImplicitThis": true,
+      "alwaysStrict": true,
+      "noUnusedLocals": false,
+      "noUnusedParameters": false,
+      "noImplicitReturns": true,
+      "noFallthroughCasesInSwitch": false,
+      "inlineSourceMap": true,
+      "inlineSources": true,
+      "experimentalDecorators": true,
+      "strictPropertyInitialization": false,
+      "typeRoots": [
+        "./node_modules/@types"
+      ]
+    },
+    "exclude": [
+      "node_modules",
+      "cdk.out"
+    ]
+  }
+

cdk/tsconfig.json

@@ -1,30 +1,11 @@
 {
   "compilerOptions": {
-    "target": "ES2020",
-    "module": "commonjs",
-    "lib": [
-      "es2020"
-    ],
-    "declaration": true,
+    "target": "es5",
+    "module": "CommonJS",
+    "moduleResolution": "node",
+    "lib": ["es2015", "es5"],
+    "sourceMap": true,
     "strict": true,
-    "noImplicitAny": true,
-    "strictNullChecks": true,
-    "noImplicitThis": true,
-    "alwaysStrict": true,
-    "noUnusedLocals": false,
-    "noUnusedParameters": false,
-    "noImplicitReturns": true,
-    "noFallthroughCasesInSwitch": false,
-    "inlineSourceMap": true,
-    "inlineSources": true,
-    "experimentalDecorators": true,
-    "strictPropertyInitialization": false,
-    "typeRoots": [
-      "./node_modules/@types"
-    ]
-  },
-  "exclude": [
-    "node_modules",
-    "cdk.out"
-  ]
+    "allowSyntheticDefaultImports": true
+  }
 }