Release prep: 54 engines, self-hosted signatures, i18n, dashboard updates

internal/transport/http/metrics.go

@@ -0,0 +1,91 @@
+package httpserver
+
+import (
+	"fmt"
+	"net/http"
+	"runtime"
+	"sync/atomic"
+	"time"
+)
+
+// Metrics collects runtime metrics for Prometheus-style /metrics endpoint.
+type Metrics struct {
+	requestsTotal   atomic.Int64
+	requestErrors   atomic.Int64
+	eventsIngested  atomic.Int64
+	incidentsTotal  atomic.Int64
+	rateLimited     atomic.Int64
+	startTime       time.Time
+}
+
+// NewMetrics creates a metrics collector.
+func NewMetrics() *Metrics {
+	return &Metrics{
+		startTime: time.Now(),
+	}
+}
+
+// IncRequests increments total request count.
+func (m *Metrics) IncRequests() { m.requestsTotal.Add(1) }
+
+// IncErrors increments error count.
+func (m *Metrics) IncErrors() { m.requestErrors.Add(1) }
+
+// IncEvents increments ingested events count.
+func (m *Metrics) IncEvents() { m.eventsIngested.Add(1) }
+
+// IncIncidents increments incident count.
+func (m *Metrics) IncIncidents() { m.incidentsTotal.Add(1) }
+
+// IncRateLimited increments rate-limited request count.
+func (m *Metrics) IncRateLimited() { m.rateLimited.Add(1) }
+
+// Middleware counts all requests.
+func (m *Metrics) Middleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		m.IncRequests()
+		next.ServeHTTP(w, r)
+	})
+}
+
+// Handler returns /metrics in Prometheus text exposition format.
+func (m *Metrics) Handler() http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		var memStats runtime.MemStats
+		runtime.ReadMemStats(&memStats)
+
+		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+
+		uptime := time.Since(m.startTime).Seconds()
+
+		fmt.Fprintf(w, "# HELP syntrex_uptime_seconds Time since server start\n")
+		fmt.Fprintf(w, "syntrex_uptime_seconds %.2f\n\n", uptime)
+
+		fmt.Fprintf(w, "# HELP syntrex_requests_total Total HTTP requests\n")
+		fmt.Fprintf(w, "syntrex_requests_total %d\n\n", m.requestsTotal.Load())
+
+		fmt.Fprintf(w, "# HELP syntrex_request_errors_total Total request errors\n")
+		fmt.Fprintf(w, "syntrex_request_errors_total %d\n\n", m.requestErrors.Load())
+
+		fmt.Fprintf(w, "# HELP syntrex_events_ingested_total Total events ingested\n")
+		fmt.Fprintf(w, "syntrex_events_ingested_total %d\n\n", m.eventsIngested.Load())
+
+		fmt.Fprintf(w, "# HELP syntrex_incidents_total Total incidents created\n")
+		fmt.Fprintf(w, "syntrex_incidents_total %d\n\n", m.incidentsTotal.Load())
+
+		fmt.Fprintf(w, "# HELP syntrex_rate_limited_total Total rate-limited requests\n")
+		fmt.Fprintf(w, "syntrex_rate_limited_total %d\n\n", m.rateLimited.Load())
+
+		fmt.Fprintf(w, "# HELP syntrex_goroutines Current goroutine count\n")
+		fmt.Fprintf(w, "syntrex_goroutines %d\n\n", runtime.NumGoroutine())
+
+		fmt.Fprintf(w, "# HELP syntrex_memory_alloc_bytes Current memory allocation\n")
+		fmt.Fprintf(w, "syntrex_memory_alloc_bytes %d\n\n", memStats.Alloc)
+
+		fmt.Fprintf(w, "# HELP syntrex_memory_sys_bytes Total memory from OS\n")
+		fmt.Fprintf(w, "syntrex_memory_sys_bytes %d\n\n", memStats.Sys)
+
+		fmt.Fprintf(w, "# HELP syntrex_gc_runs_total Total GC runs\n")
+		fmt.Fprintf(w, "syntrex_gc_runs_total %d\n", memStats.NumGC)
+	}
+}