使用托管身份配置Azure Function App与App Configuration时遇间歇性错误

我们运行基于.NET 7的隔离式v4 Azure Function App，通过Azure App Configuration获取配置项与功能标志，但应用会间歇性崩溃（每分钟发生2-3次），错误信息可查看Function App日志流截图。

相关配置 #

Host.json配置 #

{
  "version": "2.0",
  "extensions": {
    "queues": {
      "maxPollingInterval": "00:00:00.100",
      "batchSize": 32,
      "maxDequeueCount": 7
    }
  }
}

Program.cs中的App Configuration配置代码 #

var appConfigName =
   $"https://{(Environment.GetEnvironmentVariable("Environment")!.ToUpper() != "PROD" ? "shared-test" : "prod")}" +
   $"-appconfiguration.azconfig.io";

var clientId = Environment.GetEnvironmentVariable("ClientIdUserAssignedManagedIdentity");
var tokenCredential = new DefaultAzureCredential(new DefaultAzureCredentialOptions() { ManagedIdentityClientId = clientId });

config.AddAzureAppConfiguration(options =>
{
    options.Connect(new Uri(appConfigName),
            tokenCredential)
           .Select(KeyFilter.Any, LabelFilter.Null)
           .Select(KeyFilter.Any, "interservice")
           .Select(KeyFilter.Any, "intraservice-functionapp")
           .Select(KeyFilter.Any, $"{Environment.GetEnvironmentVariable("Environment")}-functionapp")
           .Select(KeyFilter.Any, $"{Environment.GetEnvironmentVariable("Environment")}-interservice")
           .ConfigureKeyVault(kv => kv.SetCredential(tokenCredential))
           .UseFeatureFlags(featureFlagOptions =>
           {
               featureFlagOptions.CacheExpirationInterval = TimeSpan.FromDays(1);
           })
           .Select(KeyFilter.Any, Environment.GetEnvironmentVariable("Environment"));
});

已尝试的方案 #

• 尝试用连接字符串连接App Configuration，但因需关联Key Vault仍需使用tokenCredential，未能解决间歇性崩溃问题。

内容的提问来源于stack exchange，提问作者pradeep