Merge pull request #21 from jkyberneees/framework-agnostic

Framework agnostic

Author: jkyberneees

README.md

@@ -1,5 +1,5 @@
 # fast-gateway
-A super fast Node.js API Gateway for the masses!  
+A super fast, framework agnostic Node.js API Gateway for the masses ❤️
 
 ## Medium articles:
 - https://medium.com/@kyberneees/node-js-api-gateway-a-developer-perspective-8defe575ed21
@@ -35,8 +35,16 @@ service.start(3000)
 ## Configuration options explained
 ```js
 {
+  // Optional server instance. Any HTTP framework that supports the following signature is compatible:
+  // - server[HTTP_METHOD](pattern, [middleware1, middleware2,], handler)
+  // 
+  // Known compatible frameworks: Restana, Express.js
+  // If omitted, restana is used as default HTTP framework
+  server, 
   // Optional restana library configuration (https://www.npmjs.com/package/restana#configuration)
-  // If the given value is a function instead of an object, it will be considered a restana service factory.
+  // If the given value is a function instead of an object, it will be considered a restana server factory.
+  //
+  // If "server" is provided, this settings are ignored.
   restana: {},
   // Optional global middlewares in the format: (req, res, next) => next() 
   // Default value: []

demos/basic-express.js

@@ -0,0 +1,42 @@
+const gateway = require('../index')
+const express = require('express')
+const PORT = process.env.PORT || 8080
+
+gateway({
+  server: express(),
+
+  middlewares: [
+    require('cors')(),
+    require('helmet')()
+  ],
+
+  routes: [{
+    prefix: '/public',
+    target: 'http://localhost:3000',
+    docs: {
+      name: 'Public Service',
+      endpoint: 'swagger.json',
+      type: 'swagger'
+    }
+  }, {
+    prefix: '/admin',
+    target: 'http://localhost:3001',
+    middlewares: [
+      require('express-jwt')({
+        secret: 'shhhhhhared-secret'
+      })
+    ]
+  }]
+}).listen(PORT, () => {
+  console.log(`API Gateway listening on ${PORT} port!`)
+})
+
+const service1 = require('restana')({})
+service1
+  .get('/hi', (req, res) => res.send('Hello World!'))
+  .start(3000).then(() => console.log('Public service listening on 3000 port!'))
+
+const service2 = require('restana')({})
+service2
+  .get('/users', (req, res) => res.send([]))
+  .start(3001).then(() => console.log('Admin service listening on 3001 port!'))

index.js

@@ -1,19 +1,22 @@
+/* eslint-disable no-useless-call */
+
 const fastProxy = require('fast-proxy')
 const restana = require('restana')
 const pump = require('pump')
 const toArray = require('stream-to-array')
 const defaultProxyHandler = (req, res, url, proxy, proxyOpts) => proxy(req, res, url, proxyOpts)
 const DEFAULT_METHODS = require('restana/libs/methods')
+const send = require('@polka/send-type')
 
 const gateway = (opts) => {
   opts = Object.assign({
     middlewares: [],
     pathRegex: '/*'
   }, opts)
 
-  const server = (opts.restana instanceof Function) ? opts.restana() : restana(opts.restana || {
+  const server = opts.server || ((opts.restana instanceof Function) ? opts.restana() : restana(opts.restana || {
     disableResponseEvent: true
-  })
+  }))
 
   // registering global middlewares
   opts.middlewares.forEach(middleware => {
@@ -26,7 +29,7 @@ const gateway = (opts) => {
     docs: route.docs
   }))
   server.get('/services.json', (req, res) => {
-    res.send(services)
+    send(res, 200, services)
   })
 
   // processing routes
@@ -40,6 +43,9 @@ const gateway = (opts) => {
     route.hooks.onRequest = route.hooks.onRequest || onRequestNoOp
     route.hooks.onResponse = route.hooks.onResponse || onResponse
 
+    // populating route middlewares
+    route.middlewares = route.middlewares || []
+
     // populating pathRegex if missing
     route.pathRegex = undefined === route.pathRegex ? opts.pathRegex : String(route.pathRegex)
 
@@ -62,14 +68,14 @@ const gateway = (opts) => {
       method = method.toLowerCase()
 
       if (server[method]) {
-        server[method](
-        // path
+        server[method].apply(server, [
+          // path
           route.prefix + route.pathRegex,
-          // route handler
-          handler(route, proxy, proxyHandler),
           // route middlewares
-          route.middlewares
-        )
+          ...route.middlewares,
+          // route handler
+          handler(route, proxy, proxyHandler)
+        ])
       }
     })
   })
@@ -100,7 +106,8 @@ const onResponse = async (req, res, stream) => {
       res.statusCode = stream.statusCode
       res.end(resBuffer)
     } catch (err) {
-      res.send(err)
+      res.statusCode = 500
+      res.end(err.message)
     }
   } else {
     res.statusCode = stream.statusCode