Add nasctl: Go NAS control plane with React frontend

internal/web/handlers_system.go

@@ -0,0 +1,75 @@
+package web
+
+import (
+	"net/http"
+	"strings"
+	"syscall"
+
+	"github.com/darroyo/nasctl/internal/system"
+)
+
+type diskUsage struct {
+	Path        string  `json:"path"`
+	TotalBytes  uint64  `json:"total_bytes"`
+	FreeBytes   uint64  `json:"free_bytes"`
+	UsedBytes   uint64  `json:"used_bytes"`
+	UsedPercent float64 `json:"used_percent"`
+}
+
+type serviceStatus struct {
+	Name   string `json:"name"`
+	Active bool   `json:"active"`
+	State  string `json:"state"`
+}
+
+func (s *Server) handleSystemStatus(w http.ResponseWriter, r *http.Request) {
+	status := map[string]any{
+		"disks":    collectDiskUsage(),
+		"services": collectServiceStatus(r),
+	}
+	writeJSON(w, http.StatusOK, status)
+}
+
+func collectDiskUsage() []diskUsage {
+	paths := []string{"/"}
+	var usages []diskUsage
+	for _, path := range paths {
+		var stat syscall.Statfs_t
+		if err := syscall.Statfs(path, &stat); err != nil {
+			continue
+		}
+		total := stat.Blocks * uint64(stat.Bsize)
+		free := stat.Bavail * uint64(stat.Bsize)
+		used := total - free
+		var pct float64
+		if total > 0 {
+			pct = float64(used) / float64(total) * 100
+		}
+		usages = append(usages, diskUsage{
+			Path:        path,
+			TotalBytes:  total,
+			FreeBytes:   free,
+			UsedBytes:   used,
+			UsedPercent: pct,
+		})
+	}
+	return usages
+}
+
+func collectServiceStatus(r *http.Request) []serviceStatus {
+	services := []string{"smbd", "nfs-server"}
+	var statuses []serviceStatus
+	for _, name := range services {
+		stdout, _, err := system.Run(r.Context(), "systemctl", "is-active", name)
+		state := strings.TrimSpace(stdout)
+		if state == "" && err != nil {
+			state = "unknown"
+		}
+		statuses = append(statuses, serviceStatus{
+			Name:   name,
+			Active: state == "active",
+			State:  state,
+		})
+	}
+	return statuses
+}