Build a Node.js web application using Express on an Azure Cloud Service
Node.js includes a minimal set of functionality in the core runtime. Developers often use 3rd party modules to provide additional functionality when developing a Node.js application. In this tutorial you will create a new application using the Express module, which provides an MVC framework for creating Node.js web applications.
A screenshot of the completed application is below:
Create a Cloud Service Project
Perform the following steps to create a new cloud service project named 'expressapp':
From the Start Menu or Start Screen, search for Azure PowerShell. Finally, right-click Azure PowerShell and select Run As Administrator.
To successfully complete this section, you must have a working installation of Node.js and the Azure SDK for Node.js for your platform.
Change directories to the c:\node directory and then enter the following commands to create a new solution named expressapp and a web role named WebRole1:
PS C:\node> New-AzureServiceProject expressapp
PS C:\Node\expressapp> Add-AzureNodeWebRole
PS C:\Node\expressapp> Set-AzureServiceProjectRole WebRole1 node 0.10.21
By default, Add-AzureNodeWebRole uses an older version of Node.js. The Set-AzureServiceProjectRole statement above instructs Azure to use v0.10.21 of Node.
Install the Express generator by issuing the following command:
PS C:\node\expressapp> npm install express-generator -g
The output of the npm command should look similar to the result below.
Change directories to the WebRole1 directory and use the express command to generate a new application:
PS C:\node\expressapp\WebRole1> express
You will be prompted to overwrite your earlier application. Enter y or yes to continue. Express will generate the app.js file and a folder structure for building your application.
To install additional dependencies defined in the package.json file, enter the following command:
PS C:\node\expressapp\WebRole1> npm install
Use the following command to copy the bin/www file to server.js. This is so the cloud service can find the entry point for this application.
PS C:\node\expressapp\WebRole1> copy bin/www server.js
After this command completes, you should have a server.js file in the WebRole1 directory.
Modify the server.js to remove one of the '.' characters from the following line.
var app = require('../app');
After making this modification, the line should appear as follows.
var app = require('./app');
This change is required since we moved the file (formerly bin/www,) to the same directory as the app file being required. After making this change, save the server.js file.
Use the following command to run the application in the Windows Azure emulator:
PS C:\node\expressapp\WebRole1> Start-AzureEmulator -launch
Modifying the View
Now modify the view to display the message "Welcome to Express in Azure".
Enter the following command to open the index.jade file:
PS C:\node\expressapp\WebRole1> notepad views/index.jade
Jade is the default view engine used by Express applications. For more information on the Jade view engine, see http://jade-lang.com.
Modify the last line of text by appending in Azure.
Save the file and exit Notepad.
Refresh your browser and you will see your changes.
After testing the application, use the Stop-AzureEmulator cmdlet to stop the emulator.
Publishing the Application to Azure
In the Azure PowerShell window, use the Publish-AzureServiceProject cmdlet to deploy the application to a cloud service
PS C:\node\expressapp\WebRole1> Publish-AzureServiceProject -ServiceName myexpressapp -Location "East US" -Launch
Once the deployment operation completes, your browser will open and display the web page.