Initial QSfera import

Server/pkg/checks/checknats.go

@@ -0,0 +1,23 @@
+package checks
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/nats-io/nats.go"
+)
+
+// NewNatsCheck checks the reachability of a nats server.
+func NewNatsCheck(natsCluster string, options ...nats.Option) func(context.Context) error {
+	return func(_ context.Context) error {
+		n, err := nats.Connect(natsCluster, options...)
+		if err != nil {
+			return fmt.Errorf("could not connect to nats server: %v", err)
+		}
+		defer n.Close()
+		if n.Status() != nats.CONNECTED {
+			return fmt.Errorf("nats server not connected")
+		}
+		return nil
+	}
+}