fix packagemanager

internal/sysinfo/packagemanager.go

@@ -4,7 +4,7 @@ import (
 	"os/exec"
 )
 
-// PackageManager is an abstraction over distro package tooling.
+// PackageManager abstracts distro package handling.
 type PackageManager interface {
 	Distro() string
 	InstallPackages(pkgs ...string) error
@@ -16,9 +16,12 @@ type PackageManager interface {
 /* ------------------------------------------------------------------ */
 
 type aptManager struct {
-	logf func(string, ...any)
+	logf    func(string, ...any) // logger from App
+	updated bool                 // true after first apt-update
 }
 
+// newPackageManager is called once in app.go; the same instance is
+// passed to every collector, so apt-update can be executed exactly once.
 func newPackageManager(logf func(string, ...any)) PackageManager {
 	return &aptManager{logf: logf}
 }
@@ -31,11 +34,27 @@ func (a *aptManager) ExecExists(bin string) bool {
 }
 
 func (a *aptManager) InstallPackages(pkgs ...string) error {
-	args := append([]string{"-y", "install"}, pkgs...)
+	if len(pkgs) == 0 {
+		return nil
+	}
+
+	// refresh package index only the first time we install anything
+	if !a.updated {
+		a.logf("apt update")
+		if err := exec.Command(
+			"apt-get", "-qq", "-y", "update",
+		).Run(); err != nil {
+			return err
+		}
+		a.updated = true
+	}
+
+	args := append(
+		[]string{"-qq", "-y", "--no-install-recommends", "install"},
+		pkgs...,
+	)
 	cmd := exec.Command("apt-get", args...)
 	cmd.Env = append(cmd.Env, "DEBIAN_FRONTEND=noninteractive")
-	cmd.Stdout = nil
-	cmd.Stderr = nil
 	a.logf("apt install %v", pkgs)
 	return cmd.Run()
 }