Application Insights Telemetry Initializer to capture responses from outbound http calls (dependencies)

DependencyResponseInitializer.cs

public class DependencyResponseInitializer : ITelemetryInitializer
{
    private readonly bool _dependencyResponseCaptureDisabled;

    public DependencyResponseInitializer(IConfiguration configuration)
    {
        bool.TryParse(configuration[Constants.ConfigKeys.DependencyResponseCapturingDisabled], out _dependencyResponseCaptureDisabled);
    }

    public void Initialize(ITelemetry telemetry)
    {
        if(_dependencyResponseCaptureDisabled)
            return;
        
        if (!(telemetry is DependencyTelemetry dependencyTelemetry) ||
            !dependencyTelemetry.TryGetOperationDetail("HttpResponse", out var reponseObject)) return;
        
        if (!(reponseObject is HttpResponseMessage response)) 
            return;
        
        foreach (var header in response.Headers)                            
            dependencyTelemetry.Properties.Add($"ResponseHeader-{header.Key}", string.Join(", ", header.Value));
        
        if (response.Content == null) 
            return;
        
        foreach (var header in response.Content.Headers)            
            dependencyTelemetry.Properties.Add($"ContentHeader-{header.Key}", string.Join(", ", header.Value));

        if (!(response.Content is StringContent) 
            && !IsTextBasedContentType(response.Headers) 
            && !IsTextBasedContentType(response.Content.Headers)) 
            return;

        var content = response.Content.ReadAsStringAsync().GetAwaiter().GetResult();
        dependencyTelemetry.Properties.Add("ResponseContent", content);
    }
    
    private static bool IsTextBasedContentType(HttpHeaders headers)
    {
        if (!headers.TryGetValues("Content-Type", out var values))
            return false;

        var header = string.Join(" ", values).ToLowerInvariant();
        var textBasedTypes = new [] { "html", "text", "xml", "json", "txt", "x-www-form-urlencoded" };
        return textBasedTypes.Any(t => header.Contains(t));
    }
}