adding consistent hashing demo

Author: jkyberneees

demos/consistent-hashing.js

@@ -0,0 +1,68 @@
+// Gateway implementation
+
+'use strict'
+
+const gateway = require('../index')
+const ConsistentHash = require('consistent-hash')
+
+const targets = [
+  'http://localhost:3000',
+  'http://localhost:3001',
+  'http://localhost:3002',
+]
+
+const consistentHash = new ConsistentHash()
+targets.forEach((target) => consistentHash.add(target))
+
+gateway({
+  routes: [
+    {
+      proxyHandler: (req, res, url, proxy, proxyOpts) => {
+        const target = consistentHash.get(req.path)
+        proxyOpts.base = target
+
+        return proxy(req, res, url, proxyOpts)
+      },
+      prefix: '/api',
+    },
+  ],
+})
+  .start(8080)
+  .then(() => console.log('API Gateway listening on 8080 port!'))
+
+// Below is the services implementation, commonly located on separated projects
+const express = require('express')
+
+// service1.js
+const service1 = express()
+service1.get('/orders/:orderId', (req, res) => {
+  res.header('Service-Id', 'service1')
+  res.send('Order from service 1!')
+})
+service1.listen(3000, () => {
+  console.log('Service 1 running!')
+})
+
+// service2.js
+const service2 = express()
+
+service2.get('/orders/:orderId', (req, res) => {
+  res.header('Service-Id', 'service2')
+  res.send('Order from service 2!')
+})
+
+service2.listen(3001, () => {
+  console.log('Service 2 running!')
+})
+
+// service3.js
+const service3 = express()
+
+service3.get('/orders/:orderId', (req, res) => {
+  res.header('Service-Id', 'service3')
+  res.send('Order from service 3!')
+})
+
+service3.listen(3002, () => {
+  console.log('Service 3 running!')
+})

package.json

@@ -32,8 +32,7 @@
     "fast-proxy-lite": "^1.1.2",
     "http-cache-middleware": "^1.4.1",
     "restana": "^4.9.9",
-    "stream-to-array": "^2.3.0",
-    "micromatch": "^4.0.8"
+    "stream-to-array": "^2.3.0"
   },
   "files": [
     "lib/",
@@ -47,6 +46,7 @@
     "artillery": "^2.0.21",
     "aws-sdk": "^2.1691.0",
     "chai": "^4.5.0",
+    "consistent-hash": "^1.2.2",
     "cors": "^2.8.5",
     "express": "^5.0.1",
     "express-jwt": "^7.7.8",