done with new version

backup.go

@@ -1,42 +1,29 @@
 package main
 
 import (
+	"archive/zip"
 	"bufio"
-	"errors"
 	"fmt"
-	"io/fs"
-	"log"
+	"io"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strings"
+	"time"
+
+	"github.com/pelletier/go-toml"
 )
 
-func parseEnvironment(key string) string {
-	value := os.Getenv(key)
-	if value == "" {
-		log.Panicf("%s is not set\n", key)
-	}
-	if _, err := os.Stat(value); err != nil {
-		if errors.Is(err, fs.ErrNotExist) {
-			log.Panicf("%s does not point to a valid path\n", key)
-		}
-		log.Panicf("trying to stat %s produced an unkown error\n", value)
-	}
-	return value
-}
+var backup_locations []string
 
-func parsePacmanConf() string {
+func parsePacmanConf() (string, error) {
+	var err error
 	var path string
 
 	file, err := os.Open("/etc/pacman.conf")
 	if err != nil {
-		log.Panicln(err)
+		return "", err
 	}
-	defer func() {
-		if err := file.Close(); err != nil {
-			log.Panicln(err)
-		}
-	}()
 
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {
@@ -48,73 +35,130 @@ func parsePacmanConf() string {
 		break
 	}
 
-	if _, err := os.Stat(path); err != nil {
-		if errors.Is(err, fs.ErrNotExist) {
-			log.Panicln("DBPath in /etc/pacman.conf does not point to a valid path")
-		}
-		log.Panicf("trying to stat %s produced an unkown error\n", path)
+	err = file.Close()
+	if err != nil {
+		return "", err
 	}
 
-	return fmt.Sprintf("%s%s", path, "local")
+	return fmt.Sprint(path, "local"), nil
 }
 
-func preBackup() {
-	pacmanDb := parsePacmanConf()
-	log.Printf("pacmanDb: %s\n", pacmanDb)
-	tmpPath := "/tmp/update/pre_backup"
+func zipIt(pathToZip string, pathToFiles string) error {
+	var err error
 
-	output, err := exec.Command("pacman",  "--verbose", "--query").Output()
+	zipFile, err := os.Create(pathToZip)
 	if err != nil {
-		log.Panicln(err)
+		return err
+	}
+
+	zipWriter := zip.NewWriter(zipFile)
+
+	walker := func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if info.IsDir() {
+			return nil
+		}
+		file, err := os.Open(path)
+		if err != nil {
+			return err
+		}
+		defer file.Close()
+
+		f, err := zipWriter.Create(path[len(pathToFiles):])
+		if err != nil {
+			return err
+		}
+
+		_, err = io.Copy(f, file)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	}
+	err = filepath.Walk(pathToFiles, walker)
+	if err != nil {
+		return err
+	}
+
+	err = zipWriter.Close()
+	if err != nil {
+		return err
+	}
+	err = zipFile.Close()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func backup(when string) error {
+	var err error
+	tmpPath := fmt.Sprint("/tmp/update/", when, "_backup")
+	pacmanDb, err := parsePacmanConf()
+	if err != nil {
+		return err
 	}
 
 	err = os.MkdirAll(tmpPath, 0755)
-
-	err = os.WriteFile(fmt.Sprintf("%s/%s", tmpPath, "pre_pacman.txt"), output, 0644)
 	if err != nil {
-		log.Panicln(err)
+		return err
 	}
-
 	defer func() {
-		if r := recover(); r != nil {
-			err := os.RemoveAll(tmpPath)
-			if err != nil {
-				log.Fatal(err)
-			}
-
-			err = CopyDir(pacmanDb, fmt.Sprintf("%s/%s", tmpPath, pacmanDb))
-			if err != nil {
-				log.Panicln(err)
-			}
-
-			log.Println("recovered successfully")
-		}
+		os.RemoveAll("/tmp/update")
 	}()
 
-	err = CopyDir(pacmanDb, fmt.Sprintf("%s/%s", tmpPath, pacmanDb))
+	output, err := exec.Command("pacman",  "--verbose", "--query").Output()
 	if err != nil {
-		log.Panicln(err)
+		return err
 	}
-}
 
-func postBackup() {
-	/*
-	 * basic logic for post:
-	 * create new pkg list and delete all lines which are the same as pre
-	 */
-	panic("unimplemented")
+	err = os.WriteFile(fmt.Sprint(tmpPath, fmt.Sprint(when, "_pacman.txt")), output, 0644)
+	if err != nil {
+		return err
+	}
+
+	if when != "post" {
+		err = CopyDir(pacmanDb, fmt.Sprint(tmpPath, "/", pacmanDb))
+		if err != nil {
+			return err
+		}
+	}
+
+	current_time := time.Now().Format(time.RFC3339)
+	pathToZip := fmt.Sprint(tmpPath, "_", current_time, ".zip")
+	err = zipIt(pathToZip, tmpPath)
+	if err != nil {
+		return err
+	}
+
+	for _, backup_location := range backup_locations {
+		err = CopyFile(pathToZip, fmt.Sprint(backup_location, "/",  when, "_backup_", current_time, ".zip"))
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
 }
 
 func main() {
-	// backup_dir := parseEnvironment("UPDATE_BACKUP_DIR")
-	cmdlineArg := os.Args[1]
-	log.Printf("cmdlineArg: %s\n", cmdlineArg)
+	os.RemoveAll("/tmp/update")
 
-	if cmdlineArg == "pre" {
-		preBackup()
-	} else if cmdlineArg == "post" {
-		postBackup()
-	} else {
-		log.Panicf("invalid cmdline argument. supplied value was: %s\n", cmdlineArg)
+	tree, err := toml.LoadFile("/etc/update.toml")
+	if err != nil {
+		fmt.Println("backup failed for the following reason: ", err)
+		os.Exit(1)
+	}
+
+	backup_locations = tree.GetArray("backup.locations").([]string)
+
+	err = backup(os.Args[1])
+	if err != nil {
+		fmt.Println("backup failed for the following reason: ", err)
+		os.Exit(1)
 	}
 }