Disable Dependency tracking in Azure Functions

Startup.cs

using Microsoft.ApplicationInsights.Channel;
using Microsoft.ApplicationInsights.DataContracts;
using Microsoft.ApplicationInsights.Extensibility;
using Microsoft.Azure.Functions.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection;
using System.Linq;

[assembly: FunctionsStartup(typeof(MyNamespace.Startup))]

namespace MyNamespace
{
    // Disable logging dependencies in Application Insights: https://github.com/Azure/Azure-Functions/issues/693#issuecomment-460798121
    // Dependencies cost SO MUCH MONEY in Application Insights, they eat up the gigabytes.
    // There potentially are some config options in host.json, however any changes I made to host.json weren't getting applied for some reason.
    // In a newly deployed function, host.json was working, but not in my existing functions... Doing this in code gives me more control anyways.
    public class Startup : FunctionsStartup
    {
        public override void Configure(IFunctionsHostBuilder builder)
        {
            var configDescriptor = builder.Services.SingleOrDefault(tc => tc.ServiceType == typeof(TelemetryConfiguration));
            if (configDescriptor?.ImplementationFactory == null)
            {
                return;
            }

            var implFactory = configDescriptor.ImplementationFactory;

            builder.Services.Remove(configDescriptor);
            builder.Services.AddSingleton(provider =>
            {
                if (!(implFactory.Invoke(provider) is TelemetryConfiguration config))
                    return null;

                config.TelemetryProcessorChainBuilder.Use(next => new DependencyErrorFilteringProcessor(next));
                config.TelemetryProcessorChainBuilder.Build();

                return config;
            });
        }
    }

    internal class DependencyErrorFilteringProcessor : ITelemetryProcessor
    {
        private readonly ITelemetryProcessor _next;
        public DependencyErrorFilteringProcessor(ITelemetryProcessor next)
        {
            _next = next;
        }

        public void Process(ITelemetry item)
        {
            // Ignore successful dependencies
            if (IsOkToSend(item))
            {
                _next.Process(item);
            }
        }

        private bool IsOkToSend(ITelemetry item)
        {
            if (item is DependencyTelemetry dependency)
            {
                // Only send failed dependencies
                return dependency.Success.HasValue && dependency.Success.Value == false;
            }

            // Ignore traces and requests
            if (item is TraceTelemetry
                || item is RequestTelemetry)
            {
                return false;
            }

            return true;
        }
    }
}