How to add custom properties to HTTPS calls so I can see them in Azure Application Insights?

Claus Appel 0
Viewed 33

I have a C# client application that calls a web application in Azure (also in written in C#, ASP .NET Core). Traffic gets captured in Azure Log Analytics so I can see it in Azure Application Insights.

When calling the web application from my client application, I would like to add some information about the version of the client application. I want this information to be easily viewable in Application Insights.

I notice that the requests table in Application Insights has a column called customDimensions. Maybe I can put stuff there, but I don't know how.

My idea is to add this information as a header and somehow configure the application to copy this information from the header into customDimensions. Is this a good way to go? If so, how do I accomplish the latter half (configure the application to copy this information from the header into customDimensions)?

azure-log-analytics azure-application-insights http-headers azure
1 Answers

You could write a telemetry initializer for this, as explained in the docs:

Use telemetry initializers to enrich telemetry with additional information or to override telemetry properties set by the standard telemetry modules.

There is a base class (TelemetryInitializerBase) that you can use which provides access to the http context to get details of the headers:

public class CustomInitializer : TelemetryInitializerBase
{
    public CustomInitializer(IHttpContextAccessor contextAccessor) : base(contextAccessor)
    {

    }

    protected override void OnInitializeTelemetry(HttpContext platformContext, RequestTelemetry requestTelemetry, ITelemetry telemetry)
    {
        var appVersion = platformContext.Request.Headers["x-app-version"].ToString();
        if(!string.IsNullOrWhiteSpace(appVersion))
            requestTelemetry.Properties["appVersion"] = appVersion;
    }
}

Add this initializer to the web app running in Azure. Then, in the customDimensions field of the request telemetry you can find the value of appVersion.

Another option is to set custom propertions in the controller action like this:

var appVersion = Request.Headers["x-app-version"].ToString();
if (!string.IsNullOrWhiteSpace(appVersion))
{
    var requestTelemetry = HttpContext.Features.Get<RequestTelemetry>();
    requestTelemetry.Properties.Add("appVersion", appVersion);
}
Peter Bons0
Related