Client-Server Application Using HTTP Api

Every developer is familiar with http api and this demo quickly illustrates how we can create a classic client-server application using http api.

Set your http resources as defined by the different paths along with the get and post methods.

You can customize your resources by defining your paths or routes with query strings and route parameters both in get and post methods.

Device1 Application

1. Create a device1 project directory and install m2m.

$ npm install m2m

2. Save the code below as device.js in your device1 project directory.

const { Device } = require('m2m');

let device = new Device(100);

device.connect(() => {

  device.get('/update-data', (req, res) => {
    console.log('req.query', req.query);
    res.json(req.query);
  });

  device.post('/machine-control/:id/actuator/:number/action/:state', (req, res) => {
    console.log('req.params', req.params);
    console.log('req.body', req.body);
    res.json({params:req.params, body:req.body});
  });

  device.post('/update-data', (req, res) => {
    console.log('req.body', req.body);
    res.send('device 100 data updated');
  });

});

3. Start your device1 application.

$ node device.js

Device2 Application

1. Create a device2 project directory and install m2m.

$ npm install m2m

2. Save the code below as device.js in your device2 project directory.

const { Device } = require('m2m');

let device = new Device(200);

device.connect(() => {

  device.get('/device/state', (req, res) => {
    res.json({id:100, state:'off'});
  });

  device.post('/update-data', (req, res) => {
    console.log('req.body', req.body);
    res.send('device 200 data updated');
  });

  device.post('/machine-control/:id/actuator/:number/action/:state', (req, res) => {
    console.log('req.params', req.params);
    console.log('req.body', req.body);
    res.json({params:req.params, body:req.body});
  });

});

3. Start your device2 application.

$ node device.js

Client Application

1. Create a client project directory and install m2m.

$ npm install m2m

2. Save the code below as client.js within your client project directory.

const m2m = require('m2m');

let client = new m2m.Client();

client.connect(() => {

  client.get({id:100, path:'/update-data?name=ed&status=member'}, (data) => {
    console.log('device 100 get /update-data result', data); 
  });

  client.get({id:200, path:'/device/state'}, (data) => {
    console.log('device 200 device/state result', data); 
  });

  client.post({id:100, path:'/update-data', body:{name:'Jim', age:'30'}}, (data) => {
    console.log('device 100 post /update-data result', data); 
  });

  client.post({id:200, path:'/machine-control/m120/actuator/25/action/on', body:{id:200, state:'true'}}, (data) => {
    console.log('device 200 /machine-control result', data);
  });

});

3. Start your client application.

$ node client.js