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':

1. From the Start Menu or Start Screen, search for Windows PowerShell. Finally, right-click Windows PowerShell and select Run As Administrator.

   

2. 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
   

   Note

   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. Note the parameters are case-sensitive. You can verify the correct version of Node.js has been selected by checking the engines property in WebRole1\package.json.

Install Express

1. 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.

   

2. 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.

   

3. To install additional dependencies defined in the package.json file, enter the following command:

   PS C:\node\expressapp\WebRole1> npm install
   

   

4. 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.

5. 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.

6. Use the following command to run the application in the 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".

1. 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.

2. Modify the last line of text by appending in Azure.

   

3. Save the file and exit Notepad.

4. 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.

Next steps

For more information, see the Node.js Developer Center.