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
To successfully complete this section, you must have a working installation of Node.js and the Azure SDK for Node.js for your platform.
Perform the following steps to create a new cloud service project named 'expressapp':
From the Start Menu or Start Screen, search for Windows PowerShell. Finally, right-click Windows PowerShell and select Run As Administrator.
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. 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 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 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.
For more information, see the Node.js Developer Center.