From 8572aa5222d24b5bc3b984a17da52d8439a3cda7 Mon Sep 17 00:00:00 2001
From: Ettore Di Giacinto <mudler@gentoo.org>
Date: Thu, 27 Feb 2020 23:14:36 +0100
Subject: [PATCH] Preserve cache data from deletion during uninstall

---
 cmd/install.go             | 11 ++++++-----
 pkg/installer/installer.go | 22 ++++++++++++++++------
 2 files changed, 22 insertions(+), 11 deletions(-)

diff --git a/cmd/install.go b/cmd/install.go
index 017aaf1f..c54f5265 100644
--- a/cmd/install.go
+++ b/cmd/install.go
@@ -82,11 +82,12 @@ var installCmd = &cobra.Command{
 		Debug("Solver", LuetCfg.GetSolverOptions().CompactString())
 
 		inst := installer.NewLuetInstaller(installer.LuetInstallerOptions{
-			Concurrency:   LuetCfg.GetGeneral().Concurrency,
-			SolverOptions: *LuetCfg.GetSolverOptions(),
-			NoDeps:        nodeps,
-			Force:         force,
-			OnlyDeps:      onlydeps,
+			Concurrency:                 LuetCfg.GetGeneral().Concurrency,
+			SolverOptions:               *LuetCfg.GetSolverOptions(),
+			NoDeps:                      nodeps,
+			Force:                       force,
+			OnlyDeps:                    onlydeps,
+			PreserveSystemEssentialData: true,
 		})
 		inst.Repositories(repos)
 
diff --git a/pkg/installer/installer.go b/pkg/installer/installer.go
index f0498f98..e4c927d5 100644
--- a/pkg/installer/installer.go
+++ b/pkg/installer/installer.go
@@ -21,6 +21,7 @@ import (
 	"os/exec"
 	"path/filepath"
 	"sort"
+	"strings"
 	"sync"
 
 	"github.com/ghodss/yaml"
@@ -36,11 +37,12 @@ import (
 )
 
 type LuetInstallerOptions struct {
-	SolverOptions config.LuetSolverOptions
-	Concurrency   int
-	NoDeps        bool
-	OnlyDeps      bool
-	Force         bool
+	SolverOptions               config.LuetSolverOptions
+	Concurrency                 int
+	NoDeps                      bool
+	OnlyDeps                    bool
+	Force                       bool
+	PreserveSystemEssentialData bool
 }
 
 type LuetInstaller struct {
@@ -375,7 +377,15 @@ func (l *LuetInstaller) uninstall(p pkg.Package, s *System) error {
 	// Remove from target
 	for _, f := range files {
 		target := filepath.Join(s.Target, f)
-		Info("Removing", target)
+		Debug("Removing", target)
+
+		if l.Options.PreserveSystemEssentialData &&
+			strings.HasPrefix(f, config.LuetCfg.GetSystem().GetSystemPkgsCacheDirPath()) ||
+			strings.HasPrefix(f, config.LuetCfg.GetSystem().GetSystemRepoDatabaseDirPath()) {
+			Warning("Preserve ", f, " which is required by luet ( you have to delete it manually if you really need to)")
+			continue
+		}
+
 		err := os.Remove(target)
 		if err != nil {
 			Warning("Failed removing file (not present in the system target ?)", target)