c# - 将响应正文记录到应用程序洞察依赖关系日志

Question

我想在依赖项表 Application Insight 中跟踪我的httpclient请求的响应正文。我的应用程序使用 .NET 框架 4.8 运行我创建了一个 Initializer 来使用以下代码跟踪 Dependencies 遥测：

public class TrackResponseBody : ITelemetryInitializer
{
    public void Initialize(ITelemetry telemetry)
    {
        var requestTelemetry = telemetry as DependencyTelemetry;

        if (requestTelemetry == null)
            return;

        if (requestTelemetry.TryGetOperationDetail("HttpResponse", out var responseObj))
        {
            var response = responseObj as HttpWebResponse;

            if (response != null)
            {
                using (var stream = response.GetResponseStream())
                {
                    var reader = new StreamReader(stream);
                    string result = reader.ReadToEnd();
                    requestTelemetry.Properties["ResponseBody"] = result;
                }
            }
        }
    }
}

但是当我尝试调用时reader.ReadToEnd()，我的代码会生成此异常：System.NotSupportedException: 'The stream does not support concurrent IO read or write operations.'

如果我不尝试获取正文响应，则此代码在应用程序洞察依赖项日志中正确写入。

这就是我实现我的方式HttpClient：

            var client_ = new HttpClient();

            client_.BaseAddress = new Uri("https://www.google.com");

            using (var request_ = new HttpRequestMessage())
            {
                request_.Method = new HttpMethod("GET");
                var response_ = await client_.SendAsync(request_).ConfigureAwait(false);
                var responseData_ = await response_.Content.ReadAsStringAsync().ConfigureAwait(false);
            }

有没有办法获得我的HttpClient的正文响应？

Answer 1

我自己试了下代码，在TrackResponseBody，这行代码返回null:，变量始终为null var response = responseObj as HttpWebResponse;。response

然后我做了一个小改动，而不是转换responseObj为HttpWebResponse，我只是转换responseObj为字符串，然后将其添加到requestTelemetry.Properties. 代码如下：

public class TrackResponseBody: ITelemetryInitializer
{
    public void Initialize(ITelemetry telemetry)
    {
        var requestTelemetry = telemetry as DependencyTelemetry;

        if (requestTelemetry == null)
            return;

        if (requestTelemetry.TryGetOperationDetail("HttpResponse", out var responseObj))
        {
            var response = responseObj as HttpWebResponse;

            //convert responseObj to string
            string s = responseObj.ToString();
            requestTelemetry.Properties["ResponseBody"] = s;
        }
    }

}

测试结果：