make proxy configurable

config.json

@@ -0,0 +1,17 @@
+{
+  "default": "aws",
+  "aws": {
+    "name": "aws-pricing",
+    "description": "AWS Price List API",
+    "backend": "pricing.us-east-1.amazonaws.com",
+    "path": "/offers/v1.0/aws/index.json",
+    "origin": "*"
+  },
+  "eos": {
+    "name": "fcsm-eos-api",
+    "description": "FCSM EOS API",
+    "backend": "emeia.fcsm.io",
+    "path": "/api/v1/analytics/summary",
+    "origin": "github.mikespub.net"
+  }
+}

index.js

@@ -10,7 +10,7 @@
 const https = require('https');
 const agent = new https.Agent({keepAlive: true});
 
-const backend = 'pricing.us-east-1.amazonaws.com';
+const config = require('./config.json')
 
 //https://github.com/firebase/functions-samples/blob/master/quickstarts/time-server/functions/index.js
 // CORS Express middleware to enable CORS Requests.
@@ -20,6 +20,10 @@ const backend = 'pricing.us-east-1.amazonaws.com';
 var cachedAgent = function cachedAgent(req, res) {
 	method = req.method || 'GET';
 	path = req.path || '/offers/v1.0/aws/index.json';
+	// TODO: choose proxy config based on path prefix?
+	proxy = config[config['default']]
+	backend = proxy.backend || 'pricing.us-east-1.amazonaws.com';
+	origin = proxy.origin || '*';
 	//If-Modified-Since: Sat, 05 May 2018 20:38:27 GMT
 	modified = req.get('If-Modified-Since');
 	//If-None-Match: "5e5d61fb71903f6b8f0123335154d11b"
@@ -31,7 +35,7 @@ var cachedAgent = function cachedAgent(req, res) {
 	if (match) {
 		headers['If-None-Match'] = match;
 	}
-	console.log(method + ' ' + path + ' ' + req.ips);
+	console.log(method + ' ' + path + ' ' + proxy.name + ' ' + req.ips);
 	reqInner = https.request({
 		hostname: backend,
 		port: 443,
@@ -45,7 +49,7 @@ var cachedAgent = function cachedAgent(req, res) {
 		resInner.on('data', chunk => { rawData += chunk; });
 		resInner.on('end', () => {
 			//https://expressjs.com/en/api.html#res
-			res.set('Access-Control-Allow-Origin', "*");
+			res.set('Access-Control-Allow-Origin', origin);
 			res.set('Access-Control-Allow-Methods', "GET, HEAD, OPTIONS");
 			res.set('Access-Control-Allow-Headers', "Origin, X-Requested-With, Content-Type, Accept");
 			// CHECKME: what about HEAD or GET 304? We need to expose Content-Length and ETag

package.json

@@ -1,6 +1,6 @@
 {
   "name": "gcf-cors-proxy",
-  "version": "1.0.0",
+  "version": "1.0.2",
   "description": "Basic CORS Proxy via Google Cloud Functions",
   "license": "Apache-2.0",
   "author": "mikespub",