C#•2mo ago

✅ SignalR trigger for Azure Function (isolated) does not trigger.

Trying to set up a SignalR trigger that recieves a message from the client. The negotiate work fine, and the connection gets established. I see the message being sent from the client as well, but my function never triggers. The message that gets sent: {"arguments":["Hello from client"],"invocationId":"0","streamIds":[],"target":"sendMessage","type":1} Azure function:

c#
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;

namespace HueCue.API;

public class Api(ILogger<Api> logger)
{
    private const string HubName = "ChatRoom";

    [Function("negotiate")]
    public string Negotiate(
        [HttpTrigger(AuthorizationLevel.Anonymous, "post")]
        HttpRequestData req,
        [SignalRConnectionInfoInput(HubName = HubName, ConnectionStringSetting = "AzureSignalR")]
        string connectionInfo)
    {
        logger.LogInformation($"SignalR Connection data requested: {connectionInfo}");
        
        return connectionInfo;
    }
    
    [Function(nameof(SendMessage))]
    public void SendMessage(
        [SignalRTrigger(HubName,"messages", nameof(SendMessage), ConnectionStringSetting = "AzureSignalR")]
        SignalRInvocationContext invocationContext)
    {
        // Extract the message from the arguments
        var content = invocationContext.Arguments?.Length > 0 
            ? invocationContext.Arguments[0]?.ToString() 
            : "(no content)";
        
        logger.LogInformation($"SignalR Message received: {content}");
    }
}

c#
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;

namespace HueCue.API;

public class Api(ILogger<Api> logger)
{
    private const string HubName = "ChatRoom";

    [Function("negotiate")]
    public string Negotiate(
        [HttpTrigger(AuthorizationLevel.Anonymous, "post")]
        HttpRequestData req,
        [SignalRConnectionInfoInput(HubName = HubName, ConnectionStringSetting = "AzureSignalR")]
        string connectionInfo)
    {
        logger.LogInformation($"SignalR Connection data requested: {connectionInfo}");
        
        return connectionInfo;
    }
    
    [Function(nameof(SendMessage))]
    public void SendMessage(
        [SignalRTrigger(HubName,"messages", nameof(SendMessage), ConnectionStringSetting = "AzureSignalR")]
        SignalRInvocationContext invocationContext)
    {
        // Extract the message from the arguments
        var content = invocationContext.Arguments?.Length > 0 
            ? invocationContext.Arguments[0]?.ToString() 
            : "(no content)";
        
        logger.LogInformation($"SignalR Message received: {content}");
    }
}

24 Replies

JoeyOP•2mo ago

index.html (client):

<html>
<body>
<h1>Azure SignalR Serverless Sample</h1>
<div id="messages"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/microsoft-signalr/3.1.7/signalr.min.js"></script>
<script>
    const apiBaseUrl = window.location.origin;
    const connection = new signalR.HubConnectionBuilder()
        .withUrl(apiBaseUrl + '/api')
        .configureLogging(signalR.LogLevel.Information)
        .build();
    
    connection.start().then(() => {
        console.log("Connection established");
        console.log(connection)
        connection.invoke("SendMessage", "Hello from client")
    }).catch(console.error);
</script>
</body>

</html>

<html>
<body>
<h1>Azure SignalR Serverless Sample</h1>
<div id="messages"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/microsoft-signalr/3.1.7/signalr.min.js"></script>
<script>
    const apiBaseUrl = window.location.origin;
    const connection = new signalR.HubConnectionBuilder()
        .withUrl(apiBaseUrl + '/api')
        .configureLogging(signalR.LogLevel.Information)
        .build();
    
    connection.start().then(() => {
        console.log("Connection established");
        console.log(connection)
        connection.invoke("SendMessage", "Hello from client")
    }).catch(console.error);
</script>
</body>

</html>

Unknown User•2mo ago

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JoeyOP•2mo ago

The "messages" is not the hub name, that's the category I don't have a github project, this is all the code

Unknown User•2mo ago

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JoeyOP•2mo ago

JoeyOP•2mo ago

I don't think that's the issue though, that's just the path where the negotiate endpoint lives It manages to establish the connection with that set-up

Unknown User•2mo ago

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JoeyOP•2mo ago

Think it might be this

Unknown User•2mo ago

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JoeyOP•2mo ago

If I run this function, the connection works just fine

JoeyOP•2mo ago

https://learn.microsoft.com/en-us/azure/azure-functions/functions-bindings-signalr-service-trigger?tabs=isolated-process%2Cnodejs-v4&pivots=programming-language-csharp

Azure Functions SignalR Service trigger binding

Learn to handle SignalR Service messages from Azure Functions.

JoeyOP•2mo ago

The stuff about SignalR Service integration Think I need to set up a URL to be able to use the trigger The connection works if I don't use the trigger

Unknown User•2mo ago

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JoeyOP•2mo ago

Of the js sdk?

Unknown User•2mo ago

Message Not Public

JoeyOP•2mo ago

Ah I took that straight from one of the examples

Unknown User•2mo ago

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JoeyOP•2mo ago

Makes sense, I'll try it thanks

Unknown User•2mo ago

Message Not Public

JoeyOP•2mo ago

Changed it to <script src="https://cdnjs.cloudflare.com/ajax/libs/microsoft-signalr/6.0.1/signalr.js"></script> This serverless stuff isn't too straightforward is it 😂

JoeyOP•2mo ago

Seems like I found the answer: https://stackoverflow.com/questions/73982004/local-development-with-azure-signalr-service-and-azure-functions

Stack Overflow

Local development with Azure SignalR Service and Azure Functions

I'm using Azure SignalR Services, which is running in the cloud, and running an Azure Function App, which runs locally on my laptop on localhost. I have the following hub: public class Leaderboard...

JoeyOP•2mo ago

https://learn.microsoft.com/en-us/azure/azure-signalr/signalr-howto-emulator - There's an emulator for local development

Azure SignalR Local Emulator for serverless development

Learn how to use Azure SignalR Local Emulator for serverless development

JoeyOP•2mo ago

Thanks for taking the time to look at it!

Unknown User•2mo ago

Message Not Public

Gaming

Programming

✅ SignalR trigger for Azure Function (isolated) does not trigger.

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