Azure functions queue trigger with managed identity

Question

I created an isolated process Azure functions for queue trigger. Based on link I created managed identify string using <CONNECTION_NAME_PREFIX>__queueServiceUri. This property works locally when I specify in local.settings.json. But it doesn't work when I specify in appsettings.json. Below is my program.cs code

var configuration = new ConfigurationBuilder().AddEnvironmentVariables()
    .AddCommandLine(args)
    .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
    .Build();

var host = new HostBuilder().ConfigureHostConfiguration(config => {
config.AddConfiguration(configuration);
}).ConfigureFunctionsWorkerDefaults().Build();

Function code:

 [Function("BlobQueueTrigger")]
    public async Task RunAsync([QueueTrigger("datablobqueue", Connection = "blobQueue")] string blobQueueItem)
    {}

Property in appsettings:

"blobQueue__queueServiceUri": "https://mydatastorage.queue.core.windows.net"

Have you tried setting them from azure portal ? in the configuration / app setting balde ? — Thomas, Oct 19 '22 at 20:21
yes. App setting in portal is working. Only appsettings.json property is not read. — DxG, Oct 19 '22 at 21:00
are you using out of process function app (dotnet-isolated)? — Thomas, Oct 19 '22 at 22:11
if you put a break point anywhere in your program.cs file, you see the error is thrown before hitting your code => i imagine it is due to the out of process mechanism — Thomas, Oct 20 '22 at 04:53

score 3 · Accepted Answer · edited Oct 20 '22 at 04:50

3

According to the documentation you referenced above, blobQueue__queueServiceUri must be defined as an Environment Variable, not in appsettings.json. This means you need to set it as an Application Setting in the portal. When working locally, values set in local.settings.json are indeed loaded as Environment Variables

Been a while since I dug into this, but I think it needs to access that value before it actually starts your process. Hence the custom configuration providers you have defined in Program.cs aren't yet loaded.

edited Oct 20 '22 at 04:50

Thomas

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answered Oct 19 '22 at 20:12

Harris Spivack

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yes. App setting in portal is working. I would prefer the property within the code than in portal. If it is not possible within code , then portal is the only option. – DxG Oct 19 '22 at 20:58

Azure functions queue trigger with managed identity

1 Answers1