Logging Request and response to Application Insight

Question

I'm trying to log API request payload and response data to Azure Application Insight. Using trace I can able to log. but I want to know what is the best way to log request and response data to application insight. Because data is huge, no.of API calls will be more. I can't just trace hundreds of thousands of request and response data using tracing. I tried some of the blogs like using ITelemetryInitializer/ httpcontext.feature,get, but no luck.

I want to log from c# .Net framework, Web API, not .NET Core.

Sample code which I tried.

public class AzureRequestResponseInitializer : ITelemetryInitializer
{
    public void Initialize(ITelemetry telemetry)
    {
        var requestTelemetry = telemetry as RequestTelemetry;
        
        if (requestTelemetry != null && (HttpContext.Current.Request.HttpMethod == HttpMethod.Post.ToString() || HttpContext.Current.Request.HttpMethod == HttpMethod.Get.ToString()))
        {
            using (var reader = new StreamReader(HttpContext.Current.Request.InputStream))
            {
                string requestBody = reader.ReadToEnd();
                requestTelemetry.Properties.Add("body", requestBody);
            }
        } 

Answer 1

This question is answered in https://thirum.wordpress.com/2019/08/19/logging-the-http-response-body-in-application-insights/

Please take a look.

Answer 2

You can achieve it by implementing IHttpModule that using Application Insight's TelemtryClient, see the following code:

using Microsoft.ApplicationInsights;
using Microsoft.ApplicationInsights.DataContracts;
using Contoso.Services.Logging.Extensions;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web;

namespace Contoso.Services.Logging.Modules
{
    public class CaptureTrafficModule : IHttpModule
    {
        public TelemetryClient Telemetry { get; set; }
        public void Init(HttpApplication context)
        {
            context.BeginRequest += new EventHandler(context_BeginRequest);
            context.EndRequest += new EventHandler(context_EndRequest);

            Telemetry = new TelemetryClient();
        }

        void context_BeginRequest(object sender, EventArgs e)
        {
            HttpApplication app = sender as HttpApplication;

            HttpResponse response = HttpContext.Current.Response;
            OutputFilterStream filter = new OutputFilterStream(response.Filter);
            response.Filter = filter;
            app.Context.Items["Filter"] = filter;


            StringBuilder request = new StringBuilder();
            // Write All The Headers too :
            //foreach (string key in app.Request.Headers.Keys)
            //{
            //    request.Append(key);
            //    request.Append(": ");
            //    request.Append(app.Request.Headers[key]);
            //    request.Append("\n");
            //}
            //request.Append("\n");

            byte[] bytes = app.Request.BinaryRead(app.Request.ContentLength);
            if (bytes.Count() > 0)
                request.Append(Encoding.ASCII.GetString(bytes));
            app.Request.InputStream.Position = 0;

            string operationName = $"{app.Request.HttpMethod} {app.Request.FilePath}";
            string activityId = System.Diagnostics.Activity.Current.RootId;
            app.Context.Items["OperationName"] = operationName;
            app.Context.Items["ActivityId"] = activityId;
            using (var logRequest = Telemetry.StartOperation<RequestTelemetry>(operationName, System.Diagnostics.Activity.Current.RootId, System.Diagnostics.Activity.Current.RootId))
            {
                try
                {
                    //logRequest.Telemetry.Id = $"10-{activityId}";
                    logRequest.Telemetry.Url = app.Request.Url;
                    logRequest.Telemetry.Properties["RequestBody"] = request.ToString();
                }
                catch (Exception ex)
                {
                    logRequest.Telemetry.Success = false;

                    Telemetry.TrackException(ex);
                    //throw;
                }
            }
        }

        void context_EndRequest(object sender, EventArgs e)
        {
            HttpApplication app = sender as HttpApplication;
            OutputFilterStream filter = null;
            string operationName = "", activityId = Guid.Empty.ToString(), responseStr = "NONE";

            if (app.Context.Items.Contains("OperationName"))
                operationName = app.Context.Items["OperationName"].ToString();

            if (app.Context.Items.Contains("ActivityId"))
                activityId = app.Context.Items["ActivityId"].ToString();

            if (app.Context.Items.Contains("Filter"))
            {
                filter = (OutputFilterStream)app.Context.Items["Filter"];
                responseStr = filter.ReadStream();
            }

            using (var logResponse = Telemetry.StartOperation<RequestTelemetry>(operationName, activityId, activityId))
            {
                try
                {
                    //logResponse.Telemetry.Id = $"20-{activityId}";
                    logResponse.Telemetry.Url = app.Request.Url;
                    logResponse.Telemetry.Properties["ResponseBody"] = responseStr.ToString();
                }
                catch (Exception ex)
                {
                    logResponse.Telemetry.Success = false;

                    Telemetry.TrackException(ex);
                    //throw;
                }
            }
        }



        public void Dispose()
        {
            //Does nothing
        }
    }

}