Text HTML in Rest API with Express


Create LearnExpressJSRestAPIWithRealApps folder and select to this folder in Visual Studio Code

Use the following command to install Express.JS:

npm install express --save
npm install body-parser --save
npm install cookie-parser --save
npm install multer --save

Create a new folder named api inside the server project. Create demo.api.js file inside api folder contains Rest APIs provides text/plain data for the client

var DemoAPI = {
    helloWorld: function (request, response) {
        response.setHeader('Content-Type', 'text/plain');
        response.send('Hello World');
    }
};

module.exports = DemoAPI;




Inside the api folder create a new file named index.js. This file will hold all the routes needed for rest api in server.

var express = require('express');
var router = express.Router();

var DemoAPI = require('./demo.api');

router.get('/demo/helloworld', DemoAPI.helloWorld);

module.exports = router;

At the root of server project, create a file named server.js. This will be the entry point into node application. This will start the server and listen on a local port

var express = require('express');
var app = express();

app.use('/api', require('./api/index'));

var server = app.listen(9090, function () {
	var host = server.address().address;
	var port = server.address().port;
	console.log("Server listening at http://%s:%s", host, port)
 });




At the root of server project run command: node server.js

Open http://localhost:9090/api/demo/helloworld in your browser to see the result

Hello World

Create LearnExpressJSRestAPIWithRealApps_Client folder and select to this folder in Visual Studio Code

Use the following command to install http module

npm install http --save

Create a new folder named api inside the client folder. Create demo.api.js file inside api folder contains method call Rest API from server

var http = require('http');
var BASE_URL = 'http://localhost:9090/api/';

var DemoAPIClient = {
    helloWorld: function (callback) {
        return http.get(BASE_URL + 'demo/helloworld', function (response) {
            var str = '';
            response.on('data', function (chunk) {
                str += chunk;
            });
            response.on('end', function () {
                callback({
                    status: response.statusCode,
                    body: str
                });
            });
            response.on('error', function (error) {
                callback({
                    status: response.statusCode,
                    error: error.message
                });
            });
        }).end();
    }
};

module.exports = DemoAPIClient;




At the root of client project, create a file named client.js. This will call Rest API and display results

var DemoAPIClient = require('./api/demo.api');
DemoAPIClient.helloWorld(function (result) {
    if (result.error) {
        console.log(result.error)
    } else {
        console.log('Status: ' + result.status);
        console.log('Body: ' + result.body);
    }
});
Status: 200
Body: Hello World