Where are the telemetry context properties?

Recently the change was made. Upgrading from Application Insights SDK version 0.13 to the version 0.14 you may notice that some public interfaces were changed. Specifically, public property Properties was removed from TelemetryContext class. Yes, one that mentioned in the documentation and blog post. One that is very important to enable many scenarios.

It is not a change we plan to keep for a long time. Public interface will be reverted back soon.

I thought a lot on how to explain this change and what led to this. Now I know what was the motivation of this change, I can tell that semantic versioning is designed to experiment with API surface, I know why it wasn’t immediately reverted. However I better not to go into details. I want to assure you that we understand that such a big API change should not happen again without the notice.

Version 0.14 of SDK brings great new features like ability to monitor custom performance counters. If you want to use this features and need custom properties I’d recommend to wait for the new version of SDK. If you don’t want to wait - here is a workaround (it will only work in 0.14 SDK).

If you are using context initializer - convert it to telemetry initializer. Now in telemetry initializer use ISupportProperties interface to set properties for telemetry item:

public class WorkaroundTelemetryInitializer : ITelemetryInitializer
{
    public void Initialize(ITelemetry telemetry)
    {
        var propsTelemetry = telemetry as ISupportProperties;
        if (propsTelemetry != null)
        {
            propsTelemetry.Properties["environment"] = "development";
        }
    }
}

Again, this workaround will only be needed for the version 0.14 and will not work in the next version of SDK.