Quickstart: Use Azure Cache for Redis with an ASP.NET web app

In this quickstart, you use Visual Studio 2019 to create an ASP.NET web application that connects to Azure Cache for Redis to store and retrieve data from the cache. You then deploy the app to Azure App Service.

Skip to the code on GitHub

Clone the repo https://github.com/Azure-Samples/azure-cache-redis-samples/tree/main/quickstart/aspnet on GitHub.

Prerequisites

• Azure subscription - create one for free
• Visual Studio 2019 with the ASP.NET and web development and Azure development workloads.

Create a cache

Next, you create the cache for the app.

1. To create a cache, sign in to the Azure portal. On the portal menu, select Create a resource.

   

2. On the Get Started pane, enter Azure Cache for Redis in the search bar. In the search results, find Azure Cache for Redis, and then select Create.

   

3. On the New Redis Cache pane, on the Basics tab, configure the following settings for your cache:

   Setting	Action	Description
   Subscription	Select your Azure subscription.	The subscription to use to create the new instance of Azure Cache for Redis.
   Resource group	Select a resource group, or select Create new and enter a new resource group name.	A name for the resource group in which to create your cache and other resources. By putting all your app resources in one resource group, you can easily manage or delete them together.
   DNS name	Enter a unique name.	The cache name must be a string of 1 to 63 characters that contains only numbers, letters, and hyphens. The name must start and end with a number or letter, and it can't contain consecutive hyphens. Your cache instance's host name is \<DNS name>.redis.cache.windows.net.
   Location	Select a location.	An Azure region that is near other services that use your cache.
   Cache SKU	Select a SKU.	The SKU determines the size, performance, and feature parameters that are available for the cache. For more information, see Azure Cache for Redis overview.
   Cache size	Select a cache size.	For more information, see Azure Cache for Redis overview.

4. Select the Networking tab or select Next: Networking.

5. On the Networking tab, select a connectivity method to use for the cache.

6. Select the Advanced tab or select Next: Advanced.

7. On the Advanced pane, verify or select an authentication method based on the following information:

   

   • By default, for a new Basic, Standard, or Premium cache, Microsoft Entra Authentication is enabled and Access Keys Authentication is disabled.
   • For Basic or Standard caches, you can choose the selection for a non-TLS port.
   • For Standard and Premium caches, you can choose to enable availability zones. You can't disable availability zones after the cache is created.
   • For a Premium cache, configure the settings for non-TLS port, clustering, managed identity, and data persistence.

   Important

   For optimal security, we recommend that you use Microsoft Entra ID with managed identities to authorize requests against your cache if possible. Authorization by using Microsoft Entra ID and managed identities provides superior security and ease of use over shared access key authorization. For more information about using managed identities with your cache, see Use Microsoft Entra ID for cache authentication.

8. (Optional) Select the Tags tab or select Next: Tags.

9. (Optional) On the Tags tab, enter a tag name and value if you want to categorize your cache resource.

10. Select the Review + create button.

    On the Review + create tab, Azure automatically validates your configuration.

11. After the green Validation passed message appears, select Create.

A new cache deployment occurs over several minutes. You can monitor the progress of the deployment on the Azure Cache for Redis Overview pane. When Status displays Running, the cache is ready to use.

Enable Microsoft Entra ID authentication on your cache

If you have a cache, check to see if Microsoft Entra Authentication has been enabled. If not, then enable it. We recommend using Microsoft Entra ID for your apps.

1. In the Azure portal, select the Azure Cache for Redis instance where you'd like to use Microsoft Entra token-based authentication.

2. Select Authentication from the Resource menu.

3. Check in the working pane to see if Enable Microsoft Entra Authentication is checked. If so, you can move on.

4. Select Enable Microsoft Entra Authentication, and enter the name of a valid user. The user you enter is automatically assigned Data Owner Access Policy by default when you select Save. You can also enter a managed identity or service principal to connect to your cache instance.

   

5. A popup dialog box displays asking if you want to update your configuration, and informing you that it takes several minutes. Select Yes.

   Important

   Once the enable operation is complete, the nodes in your cache instance reboots to load the new configuration. We recommend performing this operation during your maintenance window or outside your peak business hours. The operation can take up to 30 minutes.

For information on using Microsoft Entra ID with Azure CLI, see the references pages for identity.

To edit the CacheSecrets.config file

1. Create a file on your computer named CacheSecrets.config. Put it in a location where it won't be checked in with the source code of your sample application. For this quickstart, the CacheSecrets.config file is located at C:\AppSecrets\CacheSecrets.config.

2. Edit the Web.config file. Then add the following content:

   <appSettings>
       <add key="RedisHostName" value="<cache-hostname>:<port-number>"/>
   </appSettings>
   

3. Replace <cache-hostname> with your cache host name as it appears in the Overview blade of Azure Portal

4. Replace <port-number> with your cache host port number.

5. Save the file.

Update the MVC application

In this section, you can see an MVC application that presents a view that displays a simple test against Azure Cache for Redis. The MVC application can connect to your Azure Managed Redis (preview) instance when the "RedisHostName" configuration points to your Azure Managed Redis instance.

Install StackExchange.Redis

Your solution needs the StackExchange.Redis package to run. Install it, with this procedure:

1. To configure the app to use the StackExchange.Redis NuGet package for Visual Studio, select Tools > NuGet Package Manager > Package Manager Console.

2. Run the following command from the Package Manager Console window:

   Install-Package Microsoft.Azure.StackExchangeRedis
   

3. The NuGet package downloads and adds the required assembly references for your client application to access Azure Cache for Redis with the Microsoft.Azure.StackExchangeRedis client.

Connect to the cache with RedisConnection

The connection to your cache is managed by the RedisConnection class. The connection is first made in this statement from ContosoTeamStats/Controllers/HomeController.cs:

private static Task<RedisConnection> _redisConnectionFactory = RedisConnection.InitializeAsync(redisHostName: ConfigurationManager.AppSettings["RedisHostName"].ToString());

In RedisConnection.cs, you see the StackExchange.Redis namespace has been added to the code. This is needed for the RedisConnection class.

using StackExchange.Redis;

The RedisConnection code ensures that there is always a healthy connection to the cache by managing the ConnectionMultiplexer instance from StackExchange.Redis. The RedisConnection class recreates the connection when a connection is lost and unable to reconnect automatically.

The following line of code uses Microsoft Entra ID to connect to Azure Cache for Redis or Azure Managed Redis (preview) without password.

var configurationOptions = await ConfigurationOptions.Parse($"{_redisHostName}").ConfigureForAzureWithTokenCredentialAsync(new DefaultAzureCredential());

For more information, see StackExchange.Redis and the code in a GitHub repo.

Layout views in the sample

The home page layout for this sample is stored in the _Layout.cshtml file. From this page, you start the actual cache testing by clicking the Azure Cache for Redis Test from this page.

1. In Solution Explorer, expand the Views > Shared folder. Then open the _Layout.cshtml file.

2. You see the following line in <div class="navbar-header">.

   @Html.ActionLink("Azure Cache for Redis Test", "RedisCache", "Home", new { area = "" }, new { @class = "navbar-brand" })
   

   

Showing data from the cache

From the home page, you select Azure Cache for Redis Test to see the sample output.

1. In Solution Explorer, expand the Views folder, and then right-click the Home folder.

2. You should see this code in the RedisCache.cshtml file.

   @{
       ViewBag.Title = "Azure Cache for Redis Test";
   }
   
   <h2>@ViewBag.Title.</h2>
   <h3>@ViewBag.Message</h3>
   <br /><br />
   <table border="1" cellpadding="10">
       <tr>
           <th>Command</th>
           <th>Result</th>
       </tr>
       <tr>
           <td>@ViewBag.command1</td>
           <td><pre>@ViewBag.command1Result</pre></td>
       </tr>
       <tr>
           <td>@ViewBag.command2</td>
           <td><pre>@ViewBag.command2Result</pre></td>
       </tr>
       <tr>
           <td>@ViewBag.command3</td>
           <td><pre>@ViewBag.command3Result</pre></td>
       </tr>
       <tr>
           <td>@ViewBag.command4</td>
           <td><pre>@ViewBag.command4Result</pre></td>
       </tr>
       <tr>
           <td>@ViewBag.command5</td>
           <td><pre>@ViewBag.command5Result</pre></td>
       </tr>
   </table>
   

Run the app locally

By default, the project is configured to host the app locally in IIS Express for testing and debugging.

To run the app locally

1. In Visual Studio, select Debug > Start Debugging to build and start the app locally for testing and debugging.

2. In the browser, select Azure Cache for Redis Test on the navigation bar.

3. In the following example, the Message key previously had a cached value, which was set by using the Azure Cache for Redis console in the portal. The app updated that cached value. The app also executed the PING and CLIENT LIST commands.

   

Publish and run in Azure

After you successfully test the app locally, you can deploy the app to Azure and run it in the cloud.

To publish the app to Azure

1. In Visual Studio, right-click the project node in Solution Explorer. Then select Publish.

   

2. Select Microsoft Azure App Service, select Create New, and then select Publish.

   

3. In the Create App Service dialog box, make the following changes:

   Setting	Recommended value	Description
   App name	Use the default.	The app name is the host name for the app when it's deployed to Azure. The name might have a timestamp suffix added to it to make it unique if necessary.
   Subscription	Choose your Azure subscription.	This subscription is charged for any related hosting costs. If you have multiple Azure subscriptions, verify that the subscription that you want is selected.
   Resource group	Use the same resource group where you created the cache (for example, TestResourceGroup).	The resource group helps you manage all resources as a group. Later, when you want to delete the app, you can just delete the group.
   App Service plan	Select New, and then create a new App Service plan named TestingPlan. Use the same Location you used when creating your cache. Choose Free for the size.	An App Service plan defines a set of compute resources for a web app to run with.

   

4. After you configure the App Service hosting settings, select Create.

5. Monitor the Output window in Visual Studio to see the publishing status. After the app has been published, the URL for the app is logged:

   

Add the app setting for the cache

After the new app has been published, add a new app setting. This setting is used to store the cache connection information.

To add the app setting

1. Type the app name in the search bar at the top of the Azure portal to find the new app you created.

   

2. Add a new app setting named CacheConnection for the app to use to connect to the cache. Use the same value you configured for RedisHostName in your web.config file.

   

Run the app in Azure

1. In your browser, go to the URL for the app. The URL appears in the results of the publishing operation in the Visual Studio output window. It's also provided in the Azure portal on the overview page of the app you created.

2. Select Azure Cache for Redis Test on the navigation bar to test cache access as you did with the local version.

Clean up resources

If you want to continue to use the resources you created in this article, keep the resource group.

Otherwise, if you're finished with the resources, you can delete the Azure resource group that you created to avoid charges.

To delete a resource group

1. Sign in to the Azure portal, and then select Resource groups.

2. Select the resource group you want to delete.

   If there are many resource groups, use the Filter for any field... box, type the name of your resource group you created for this article. Select the resource group in the results list.

   

3. Select Delete resource group.

4. You're asked to confirm the deletion of the resource group. Type the name of your resource group to confirm, and then select Delete.

   

After a few moments, the resource group and all of its resources are deleted.

Next steps

• Connection resilience
• Best Practices Development