.NET Aspire Azure Web PubSub integration
In this article, you learn how to use the .NET Aspire Azure Web PubSub integration. The Aspire.Azure.Messaging.WebPubSub library offers options for registering an WebPubSubServiceClient in the DI container for connecting to Azure Web PubSub.
Prerequisites
- Azure subscription: create one for free.
- An existing Azure Web PubSub service instance. For more information, see Create a Web PubSub resource. Alternatively, you can use a connection string, which isn't recommended in production environments.
Get started
To get started with the .NET Aspire Azure Web PubSub integration, install the 📦 Aspire.Azure.Messaging.WebPubSub NuGet package in the client-consuming project, i.e., the project for the application that uses the Azure Web PubSub client.
dotnet add package Aspire.Azure.Messaging.WebPubSub
For more information, see dotnet add package or Manage package dependencies in .NET applications.
Example usage
In the Program.cs file of your project, call the AddAzureWebPubSubHub extension method to register a WebPubSubServiceClient for use via the dependency injection container. The method takes a connection name parameter.
builder.AddAzureWebPubSubServiceClient("wps");
You can then retrieve the WebPubSubServiceClient instance using dependency injection. For example, to retrieve the client from a service:
public class ExampleService(WebPubSubServiceClient client)
{
// Use client...
}
For more information, see the Azure.Messaging.WebPubSub documentation.
App host usage
To add Azure Web PubSub hosting support to your IDistributedApplicationBuilder, install the 📦 Aspire.Hosting.Azure.WebPubSub NuGet package in the app host project.
dotnet add package Aspire.Hosting.Azure.WebPubSub
In your app host project, add a Web PubSub connection and consume the connection using the following methods:
var webPubSub = builder.AddAzureWebPubSub("wps");
var exampleService = builder.AddProject<Projects.ExampleService>()
.WithReference(webPubSub);
The AddAzureWebPubSubHub method reads connection information from the app host's configuration (for example, from "user secrets") under the ConnectionStrings:wps configuration key. The WithReference method passes that connection information into a connection string named wps in the ExampleService project. In the Program.cs file of ExampleService, the connection can be consumed using:
builder.AddAzureWebPubSubServiceClient("wps");
Configuration
The .NET Aspire Azure Web PubSub library provides multiple options to configure the Azure Web PubSub connection based on the requirements and conventions of your project. Note that either a Endpoint or a ConnectionString is a required to be supplied.
Use a connection string
When using a connection string from the ConnectionStrings configuration section, you can provide the name of the connection string when calling builder.AddAzureWebPubSubHub():
builder.AddAzureWebPubSubServiceClient(
"WebPubSubConnectionName",
"your_hub_name");
And then the connection information will be retrieved from the ConnectionStrings configuration section. Two connection formats are supported:
Use the service endpoint
The recommended approach is to use the service endpoint, which works with the AzureMessagingWebPubSubSettings.Credential property to establish a connection. If no credential is configured, the DefaultAzureCredential is used.
{
"ConnectionStrings": {
"WebPubSubConnectionName": "https://xxx.webpubsub.azure.com"
}
}
Connection string
Alternatively, a connection string can be used.
{
"ConnectionStrings": {
"WebPubSubConnectionName": "Endpoint=https://xxx.webpubsub.azure.com;AccessKey==xxxxxxx"
}
}
Use configuration providers
The .NET Aspire Azure Web PubSub library supports Microsoft.Extensions.Configuration. It loads the AzureMessagingWebPubSubSettings and WebPubSubServiceClientOptions from configuration by using the Aspire:Azure:Messaging:WebPubSub key. Consider the example appsettings.json that configures some of the options:
{
"Aspire": {
"Azure": {
"Messaging": {
"WebPubSub": {
"DisableHealthChecks": true,
"HubName": "your_hub_name"
}
}
}
}
}
Use inline delegates
You can also pass the Action<AzureMessagingWebPubSubSettings> configureSettings delegate to set up some or all the options inline, for example to disable health checks from code:
builder.AddAzureWebPubSubServiceClient(
"wps",
settings => settings.DisableHealthChecks = true);
You can also setup the WebPubSubServiceClientOptions using the optional Action<IAzureClientBuilder<WebPubSubServiceClient, WebPubSubServiceClientOptions>> configureClientBuilder parameter of the AddAzureWebPubSubHub method. For example, to set the client ID for this client:
builder.AddAzureWebPubSubServiceClient(
"wps",
configureClientBuilder: clientBuilder =>
clientBuilder.ConfigureOptions(options => options.Retry.MaxRetries = 5));
Health checks
By default, .NET Aspire integrations enable health checks for all services. For more information, see .NET Aspire integrations overview.
The .NET Aspire Azure Web PubSub integration handles exposes a configurable health check that reports as healthy, when the client can successfully connect to the Azure Web PubSub service.
Observability and telemetry
.NET Aspire integrations automatically set up Logging, Tracing, and Metrics configurations, which are sometimes known as the pillars of observability. For more information about integration observability and telemetry, see .NET Aspire integrations overview. Depending on the backing service, some integrations may only support some of these features. For example, some integrations support logging and tracing, but not metrics. Telemetry features can also be disabled using the techniques presented in the Configuration section.
Logging
The .NET Aspire Azure Web PubSub integration uses the following log categories:
AzureAzure.CoreAzure.IdentityAzure.Messaging.WebPubSub
Tracing
The .NET Aspire Azure Web PubSub integration will emit the following tracing activities using OpenTelemetry:
- "Azure.Messaging.WebPubSub.*"
Metrics
The .NET Aspire Azure Web PubSub integration currently doesn't support metrics by default due to limitations with the Azure SDK for .NET. If that changes in the future, this section will be updated to reflect those changes.
See also
.NET Aspire