Bash Functions for Simple Directory Backup

backup-functions.sh

checkBackupTarget() {
    [ ! "$1" ] \
    && echo "Usage: $FUNCNAME [ directory-to-backup ]" \
    && echo "Note: the path should be relative" \
    && return 2

    local tgtPath=$1

    [ ! -d "$tgtPath" ] \
    && printf "$FUNCNAME : \"%s\" does NOT exist!!!\n" "$tgtPath" \
    && return 1

    [[ ${tgtPath:0:1} = "/" || ${tgtPath:0:1} = "~" ]] \
    && echo "$FUNCNAME : Absolute path is not allowed!!!" \
    && return 1

    return 0
}

pushBackup() {
    checkBackupTarget $1 || return 1

    local tgtPath=$1
    local absSrcPath=$( realpath "$tgtPath" )
    local backupPath="$HOME/__backup__$absSrcPath"
    local dateTime=$( date "+%y-%m-%d_%Hh%Mm%Ss" )

    mkdir -p "$backupPath" \
    && backupPath="${backupPath}/${dateTime}.bz" \
    && tar jcf "$backupPath" "$tgtPath" \
    && echo "$FUNCNAME : new backup created as => $backupPath"
}

printBackups() {
    checkBackupTarget $1 || return 1
    local tgtPath=$1
    local backupPath="$HOME/__backup__$PWD/$tgtPath"
    [ ! -d "$backupPath" ] && printf "$FUNCNAME : \"%s\" does NOT exist!!!\n" "$backupPath" && return 1
    
    __stored_backup_files__=() ### Output from this function
    cd $backupPath
    local iii
    for file in *; do
        iii=${#__stored_backup_files__[@]}
        printf "\t[%d] %s\n" $iii $file
        __stored_backup_files__[$iii]=$file
    done;
    cd "$OLDPWD"
}

alias listBackups='printBackups'

deleteBackup() {
    printBackups $1

    echo "$FUNCNAME : Please pick a version to delete from ( 0..$(( ${#__stored_backup_files__[@]} - 1 )) )"
    echo "$FUNCNAME : Or press n to quit without doing anything"
    local index
    read index
    [[ $index = "n" || $index -lt 0 || $index -ge ${#__stored_backup_files__[*]} ]] && echo "$FUNCNAME : Exit without doing anything" && return

    local tgtPath=$1
    local backupPath="$HOME/__backup__$PWD/$tgtPath"
    local targetFile="${backupPath}/${__stored_backup_files__[$index]}"
    unset __stored_backup_files__
    echo "$FUNCNAME : You have chosen \"$targetFile\""

    tput setaf 6
    rm -rfi "$targetFile"
    tput sgr 0
}

pullBackup() {
    printBackups $1

    local tgtPath=$1
    local backupPath="$HOME/__backup__$PWD/$tgtPath"

    echo "$FUNCNAME : Please pick a version to restore from ( 0..$(( ${#__stored_backup_files__[@]} - 1 )) )"
    echo "$FUNCNAME : Or press n to quit without doing anything"
    read index
    [[ $index = "n" || $index -lt 0 || $index -ge ${#__stored_backup_files__[*]} ]] && echo "$FUNCNAME : Exit without doing anything" && return

    targetFile=${__stored_backup_files__[$index]}
    unset __stored_backup_files__
    echo "$FUNCNAME : You have chosen $targetFile"    

    if [ -e "$tgtPath" ]; then
        # If $tgtPath exists, rename it rather than overwriting it
        local dateTime=$( date "+%y-%m-%d_%Hh%Mm%Ss" )
        local tmpPath="$dateTime--$tgtPath"
        printf "$FUNCNAME : '%s' exists... renaming it to '%s'\n" "$tgtPath" "$tmpPath"
        mv "$tgtPath" "$tmpPath"
    fi

    tar jxf "$backupPath/$targetFile" && printf "$FUNCNAME : Now '%s' has been restored from '%s'\n" "$tgtPath" "$targetFile"
}

HOW TO:

These Bash functions manage multiple backups for an arbitrary directory and all of its subdirectories.
All backup files (snapshots) will be compressed and stored at ~/__backup__ folder

All commands accept a name of a directory to backup.
I recommend you to run the commands from the target folder's parent directory.
[NOTE] Specifying an absolute path as a parameter is not allowed.

• Create a backup for the current snapshot of a folder
  • $ pushBackup my-work
• List all snapshots
  • $ listBackups my-work
• Restore the folder from one of the snapshots
  • $ pullBackup someData
• Delete all the snapshot
  • $ deleteBackup someData

The backup snapshots will be named as follows to show their time of saving:

$ listBackups  my-work
    [0] 16-04-20_12h06m49s.bz
    [1] 16-04-21_12h42m57s.bz
    [2] 16-04-25_12h36m21s.bz
    [3] 16-04-29_16h05m19s.bz
    [4] 16-04-29_18h43m33s.bz
    [5] 16-04-30_12h21m15s.bz
    [6] 16-05-02_11h12m14s.bz