While we have used restify to create this simple service, there are several alternative approaches that we could have used, such as:

• The Node core http module
• The Express framework http://expressjs.com/
• The HAPI framework https://hapijs.com/

Let's create an alternative implementation using the Node core HTTP module. We'll copy the micro folder to micro-core-http and alter the service.js file in the micro-core-http/adderservice folder to the following:

const http = require('http')

 const server = http.createServer(respond)

 server.listen(8080, function () {
   console.log('listening on port 8080')
 })

 function respond (req, res) {
   const [cmd, first, second] = req.url.split('/').slice(1)
   const notFound = cmd !== 'add' || 
     first === undefined || 
     second === undefined

   if (notFound) {
     error(404, res)
     return
   }

   const result = parseInt(first, 10) + parseInt(second, 10)
   res.end(result)
 }

 function error(code, res) {
   res.statusCode = code
   res.end(http.STATUS_CODES[code])
 }

We can start our service, as in the main recipe, with:

$ node service.js 

We can use curl as before to test our service:

$ curl http://localhost:8080/add/1/2 

While using the core http module can give us the same results, we have to implement additional lower level logic. Neglecting edge cases or misunderstanding fundamentals can lead to brittle code. The framework support provided by the restify module also supplies us with conveniences such as parameter parsing, automated error handling, middleware support, and so forth.