HttpContext和TelemetryInitializer

Question

我希望将用户的"client_id“声明作为属性附加到发送到Application的每个请求中。

根据我所读到的，我应该实现ITelemetryInitializer，但是为了检索"client_id“，我需要请求的HttpContext。见我的首字母：

public class ClaimTelemetryInitializer : ITelemetryInitializer
{
    public HttpContext HttpContext { get; set; }

    public void Initialize(ITelemetry telemetry)
    {
        this.AddTelemetryContextPropertFromClaims(telemetry, "client_id");
    }

    private void AddTelemetryContextPropertFromClaims(ITelemetry telemetry, string claimName)
    {
        if (HttpContext != null)
        {
            var requestTelemetry = telemetry as RequestTelemetry;

            var claim = HttpContext.User.Claims.SingleOrDefault(x => x.Type.Equals(claimName, StringComparison.InvariantCultureIgnoreCase));

            if (claim != null)
            {
                telemetry.Context.Properties[claimName] = claim.Value;
            }
        }
    }
}

我可以创建一个动作过滤器来每次设置上下文，但这感觉很糟糕：

public class TrackClaimsAttribute : ActionFilterAttribute
{
    public override Task OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)
    {
        var initialiser = TelemetryConfiguration.Active.TelemetryInitializers.OfType<ClaimTelemetryInitializer>().Single();

        initialiser.HttpContext = context.HttpContext;

        return base.OnActionExecutionAsync(context, next);
    }
}

有没有更好的方法来实现我想做的事？

Answer 1

您应该实现WebTelemetryInitializerBase，它为您提供HttpContext。

您的代码应该如下所示：

public class ClaimTelemetryInitializer : WebTelemetryInitializerBase
{
    protected override void OnInitializeTelemetry(
            HttpContext platformContext,
            RequestTelemetry rootRequestTelemetry, 
            ITelemetry telemetry) {

            var claim = HttpContext.User.Claims.SingleOrDefault(x => x.Type.Equals(claimName, StringComparison.InvariantCultureIgnoreCase));

            if (claim != null)
            {
                telemetry.Context.Properties[claimName] = claim.Value;
            }
    }
}

Answer 2

我建议在HttpContextAccessor类的构造函数中注入一个ClaimTelemetryInitializer实例，然后您可以使用它从HttpContext中提取值。或者，更好的是，为您的TelemetryInitializer创建一个基类，并使用它的构造函数注入HttpContextAccessor实例。

例如：

    protected ClaimTelemetryInitializer(IHttpContextAccessor httpContextAccessor)
    {
        this.httpContextAccessor = httpContextAccessor;
    }

    public void Initialize(ITelemetry telemetry)
    {
        var context = this.httpContextAccessor.HttpContext;
        if (context == null)
        {
            return;
        }

        var claim = context.User.Claims.SingleOrDefault(x => x.Type.Equals(claimName, StringComparison.InvariantCultureIgnoreCase));
        //Do logic here...
    }

Answer 3

我希望这是设计成AppInsights的，但是您可以直接使用静态HttpContext.Current。您可以使用它的每个请求的Items字典作为短期(接近无状态)存储空间，将您的自定义值传递给自定义遥测处理程序。

所以试试

class AppInsightCustomProps : ITelemetryInitializer
{
    public void Initialize(ITelemetry telemetry)
    {
        var requestTelemetry = telemetry as RequestTelemetry;
        // Is this a TrackRequest() ?
        if (requestTelemetry == null) return;

        var httpCtx = HttpContext.Current;
        if (httpCtx != null)
        {
            var customPropVal = (string)httpCtx.Items["PerRequestMyCustomProp"];
            if (!string.IsNullOrWhiteSpace(customPropVal))
            {
                requestTelemetry.Properties["MyCustomProp"] = customPropVal;
            }
        }
    }
}

并对所需的自定义属性进行编程，在请求管道中的任何位置都有以下内容

if (HttpContext.Current != null)
{
    HttpContext.Current.Items["PerRequestMyCustomProp"] = myCustomPropValue;
}