How did you collect metrics and monitor?

Metrics collection and monitoring are typically implemented using specialized tools and libraries that allow collecting, aggregating, and visualizing application data.

In the context of Go and modern systems, the following approaches are often used:

• Metrics collection tools: Prometheus, StatsD, OpenTelemetry.
• Integration libraries: for example, prometheus/client_golang for exporting metrics from Go applications.
• Types of metrics: counters, histograms, timers, gauges.

Example of metrics collection in Go with Prometheus:

import (
    "github.com/prometheus/client_golang/prometheus"
    "github.com/prometheus/client_golang/prometheus/promhttp"
    "net/http"
)

var (
    requestCounter = prometheus.NewCounterVec(
        prometheus.CounterOpts{
            Name: "http_requests_total",
            Help: "Number of HTTP requests",
        },
        []string{"path", "method", "status"},
    )
)

func init() {
    prometheus.MustRegister(requestCounter)
}

func handler(w http.ResponseWriter, r *http.Request) {
    // handle request
    w.WriteHeader(http.StatusOK)
    w.Write([]byte("OK"))

    requestCounter.WithLabelValues(r.URL.Path, r.Method, "200").Inc()
}

func main() {
    http.HandleFunc("/", handler)
    http.Handle("/metrics", promhttp.Handler())
    http.ListenAndServe(":8080", nil)
}

Monitoring

• Metrics are collected and aggregated in a monitoring system (e.g., Prometheus).
• Dashboards (Grafana) are used for visualization.
• Alerts are configured based on metrics for timely response.

Thus, metrics collection and monitoring are a comprehensive process involving code instrumentation, data collection, visualization, and alerting.