add additional CORS headers

Author: u jann

README.md

@@ -23,7 +23,11 @@ exports.handler = router.handler(
 {
     // for handling an http-call from an AWS Apigateway proxyIntegration we provide the following config:
     proxyIntegration: {
-        // activate CORS on all http-methods (OPTIONS requests are handled automagically):
+        // activate CORS on all http-methods (OPTIONS requests are handled automagically);
+        // if set to true, these default headers will be sent on every response:
+        // "Access-Control-Allow-Origin" = "'*'"
+        // "Access-Control-Allow-Methods" = "'GET,POST,PUT,DELETE,HEAD'"
+        // "Access-Control-Allow-Headers" = "'Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token'"
         cors: true,
         routes: [
             {

lib/proxyIntegration.js

@@ -21,6 +21,8 @@ function process(proxyIntegrationConfig, event) {
     let headers = {};
     if (proxyIntegrationConfig.cors) {
         headers["Access-Control-Allow-Origin"] = "*";
+        headers["Access-Control-Allow-Methods"] = "'GET,POST,PUT,DELETE,HEAD'";
+        headers["Access-Control-Allow-Headers"] = "'Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token'";
         if (event.httpMethod === 'OPTIONS') {
             return Promise.resolve({statusCode: 200, headers: headers, body: ''});
         }

test/proxyIntegration.spec.js

@@ -14,6 +14,11 @@ function forEach(arrayOfArrays) {
 }
 
 const proxyIntegration = require('../lib/proxyIntegration');
+const expectedCorsHeaders = {
+    "Access-Control-Allow-Origin": "*",
+    "Access-Control-Allow-Methods": "'GET,POST,PUT,DELETE,HEAD'",
+    "Access-Control-Allow-Headers": "'Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token'"
+};
 
 describe('proxyIntegration.routeHandler.selection', () => {
     it('should select longer match', () => {
@@ -106,9 +111,7 @@ describe('proxyIntegration.routeHandler.selection', () => {
         }, {httpMethod: 'OPTIONS', path: '/'}).then(result => {
             expect(result).toEqual({
                 statusCode: 200,
-                headers: {
-                    "Access-Control-Allow-Origin": "*"
-                },
+                headers: expectedCorsHeaders,
                 body: ''
             });
             done();
@@ -121,10 +124,7 @@ describe('proxyIntegration.routeHandler.selection', () => {
         }, {httpMethod: 'GET', path: '/'}).then(result => {
             expect(result).toEqual({
                 statusCode: 200,
-                headers: {
-                    "Content-Type": "application/json",
-                    "Access-Control-Allow-Origin": "*"
-                },
+                headers: Object.assign({"Content-Type": "application/json"}, expectedCorsHeaders),
                 body: '"/"'
             });
             done();
@@ -307,7 +307,7 @@ describe('proxyIntegration.routeHandler', () => {
             expect(result).toEqual({
                 statusCode: 501,
                 body: 'bla',
-                headers: {"Content-Type": "application/json", "Access-Control-Allow-Origin": "*"}
+                headers: Object.assign({"Content-Type": "application/json"}, expectedCorsHeaders)
             });
             done();
         });