Implement metrics collection for API server (#143)

helpers.go

@@ -0,0 +1,52 @@
+package main
+
+import (
+	"net"
+	"net/http"
+
+	"github.com/Luzifer/ots/pkg/metrics"
+	"github.com/Luzifer/ots/pkg/storage"
+	"github.com/sirupsen/logrus"
+)
+
+func requestInSubnetList(r *http.Request, subnets []string) bool {
+	if len(subnets) == 0 {
+		// No subnets specififed: None allowed (without doing the parsing)
+		return false
+	}
+
+	remote, _, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		logrus.WithError(err).Error("parsing remote address")
+		return false
+	}
+
+	remoteIP := net.ParseIP(remote)
+	if remoteIP == nil {
+		logrus.WithError(err).Error("parsing remote address")
+		return false
+	}
+
+	for _, sn := range subnets {
+		_, netw, err := net.ParseCIDR(sn)
+		if err != nil {
+			logrus.WithError(err).WithField("subnet", sn).Warn("invalid subnet specified")
+			continue
+		}
+
+		if netw.Contains(remoteIP) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func updateStoredSecretsCount(store storage.Storage, collector *metrics.Collector) {
+	n, err := store.Count()
+	if err != nil {
+		logrus.WithError(err).Error("counting stored secrets")
+		return
+	}
+	collector.UpdateSecretsCount(n)
+}