Azure App Config: Create Feature Flag using Azure.Data.AppConfiguration namespace

AzureAppConfigExtensions.cs

namespace FeatureFlags.Extensions
{
    using System;
    using Azure;
    using Azure.Data.AppConfiguration;
    using Microsoft.AspNetCore.Hosting;
    using Microsoft.AspNetCore.Mvc.Filters;
    using Microsoft.Extensions.Configuration;
    using Microsoft.Extensions.Configuration.AzureAppConfiguration;
    using Microsoft.Extensions.DependencyInjection;
    using Microsoft.FeatureManagement;
    using Newtonsoft.Json;

    public static class AzureAppConfigExtensions
    {
        public static async Task InitialiseFlags(string connectionString, string label, Feature[] featureFlags)
        {
            var client = new ConfigurationClient(connectionString);

            /* Loop the flags and create as disabled the first time */
            
            foreach (var flag in featureFlags)
            {
                var featureModel = new CreateFeatureModel()
                {
                    Enabled = false,
                    Id = flag.Id,
                    Description = flag.Description
                };

                var config = JsonConvert.SerializeObject(featureModel);

                try
                {
                    /* A feature flag needs this exact name as a prefix followed by your key */
                    /* It also needs the exact content type too or it will add as a config entry */
                    
                    await client.AddConfigurationSettingAsync(new ConfigurationSetting(".appconfig.featureflag/" + flag.Id, config, label)
                    {
                        ContentType = "application/vnd.microsoft.appconfig.ff+json;charset=utf-8"
                    });
                }
                catch (RequestFailedException exception) when (exception.Status == 412)
                {
                    /* If the exception is a 412, it more than likely already in the instance, so ignore it */
                    
                    if (!exception.Message.ToLower().Contains("setting was already present"))
                    {
                        throw;
                    }
                }
            }
        }
    }
}

^^ Not sure if the async methods actually exists or not, sure would be nice oif they did, though this runs on app start anyway, so reckon you'd be ok with it being sync anyway.