.net core 使用 prometheus 监控 nats 请求答案

【问题标题】：.net core monitor nats request with prometheus.net core 使用 prometheus 监控 nats 请求
【发布时间】：2020-06-28 12:56:10
【问题描述】：

我有一个与 nats 集成的 net core 3.1 web-API 应用程序我需要捕获所有应用程序的流量并将它们发送到 Prometheus 以监控应用程序的活动在这种情况下，我使用了this 文章，但它描述了一种捕获 Http 请求而不是 nats 的方法有没有人遇到过这样的问题？

【问题讨论】：

标签： c# .net-core prometheus nats.io

【解决方案1】：

我终于明白了！如果有人有同样的问题这是我的解决方案：

    {
        private readonly ITracer _tracer;

        public TraceMiddleware(ITracer tracer)
        {
            _tracer = tracer;
        }

        public async Task ExecuteAsync(NatsContext context, PipelineDelegate next)
        {
            var operationName = $"{context.Request.Address.Service}:{context.Request.Address.Method}";
            var builder = _tracer.BuildSpan(operationName);

            #region [Context TraceId]

            builder.WithTag("internalRequestId", context["requestId"].ToString());

            context.Tracer.AddTracer(context.Request.Address.ToNatsSubject(), context["requestId"].ToString());


            builder.WithTag("TraceId", context.Tracer.TraceId);

            #endregion

            using (var scope = builder.StartActive(false))
            {
                var span = scope.Span;
                span.SetTag("flow", context.Tracer.ToString());
                span.SetTag("request-route", context.Request.Address.ToNatsSubject());
                span.Log(DateTimeOffset.UtcNow, "request-started");

            #region [Prometheus]

                var counter = Metrics.CreateCounter("app_request_total", "Nats Requests Total",
                    new CounterConfiguration
                    {
                        LabelNames = new[] {"path", "method", "statusCode"}
                    });

                var path = context.Request.Address.Service;
                var method = context.Request.Address.Method;
                int statusCode;
                try
                {
                    await next();
                }
                catch (Exception)
                {
                    statusCode = 500;
                    counter.Labels(path, method, statusCode.ToString()).Inc();
                    throw;
                }

                statusCode = (int) context.Response.Status;
                counter.Labels(path, method, statusCode.ToString()).Inc();

            #endregion

                span.Log(DateTimeOffset.UtcNow, "request-finished");
                var logData = new List<KeyValuePair<string, object>>
                {
                    new KeyValuePair<string, object>("status-code", context.Response.Status),
                    new KeyValuePair<string, object>("has-exception", context.Response.Error != null)
                };
                span.Log(logData);
                span.Finish();
            }
        }
    }```

【讨论】：