List the files in Directory and Copy-Replace them into another Directory in Linux - bash

Question

I am trying to automate the below: Any help, please.
We have 2 directories as mentioned below, whenever we get new files in Directory-1, only they should be copied and replaced into Directory-2. How to achieve this in Linux scripting. Filename remains the same but the version will be different.
Directory-1:
FileOne_2.0.0.txt
FileTwo_3.0.0.txt
Directory-2:
FileOne_1.0.0.txt
FileTwo_2.0.0.txt
FileThree_3.0.0.txt
FileFive_5.0.0.txt

Answer 1

Try this code (on a test setup before you trust your real directories and files with it):
#! /bin/bash -p
shopt -s extglob # Enable extended globbing ( +([0-9]) ... )
shopt -s nullglob # Globs that match nothing expand to nothing
shopt -s dotglob # Globs match files with names starting with '.'
srcdir='Directory-1'
destdir='Directory-2'
# A(n extended) glob pattern to match a version string (e.g. '543.21.0')
readonly kVERGLOB='+([0-9]).+([0-9]).+([0-9])'
# shellcheck disable=SC2231 # (Bad warning re. unquoted ${kVERGLOB})
for srcpath in "$srcdir"/*_${kVERGLOB}.txt; do
srcfile=${srcpath##*/} # E.g. 'FileOne_2.0.0.txt'
srcbase=${srcfile%_*} # E.g. 'FileOne'
# Set and check the path that the file will be moved to
destpath=$destdir/$srcfile
if [[ -e $destpath ]]; then
printf "Warning: '%s' already exists. Skipping '%s'.\\n" \
"$destpath" "$srcpath" >&2
continue
fi
# Make a list of the old versions of the file
# shellcheck disable=SC2206 # (Bad warning re. unquoted ${kVERGLOB})
old_destpaths=( "$destdir/$srcbase"_${kVERGLOB}.txt )
# TODO: Add checks that the number of old files (${#old_destpaths[*]})
# is what is expected (exactly one?)
# Move the file
if mv -i -- "$srcpath" "$destpath"; then
printf "Moved '%s' to '%s'\\n" "$srcpath" "$destpath" >&2
else
printf "Warning: Failed to move '%s' to '%s'. Skipping '%s'.\\n" \
"$srcpath" "$destpath" "$srcpath" >&2
continue
fi
# Remove the old version(s) of the file (if any)
for oldpath in "${old_destpaths[#]}"; do
if rm -- "$oldpath"; then
printf "Removed '%s'\\n" "$oldpath" >&2
else
printf "Warning: Failed to remove '%s'.\\n" "$oldpath" >&2
fi
done
done
The code is Shellcheck-clean. Two Shellcheck suppression comments are used because the unquoted expansions are necessary here.
srcdir and destdir are set to constant values. You might want to take them from command line parameters, or set them to different constant values.
The code could be made shorter by removing checks. However, moves and removes are destructive operations that can do a lot of damage if they are done incorrectly. I'd add even more checks if it was my own data.
See glob - Greg's Wiki for an explanation of the "extended globbing" used in the code.
See Parameter expansion [Bash Hackers Wiki] for an explanation of ${srcpath##*/} and ${srcfile%_*}.
mv -i is used as a double protection against overwriting an existing file.
All external commands are invoked with -- to explicitly end options, in case they are ever used with paths that begin with -.
Make sure that you understand the code and test it VERY carefully before using it for real.

Answer 2

source_dir=./files/0
dest_dir=./files/1/
for file in $source_dir/*
do
echo $file
echo "processing"
if [[ "1" == "1" ]]; then
mv $file $dest_dir
fi
done
Where processing and the 1 == 1 is whatever your 'prechecks' are (which you haven't told us)

Answer 3

If your coreutils sort is newer than or equal to v7.0 (2008-10-5) after which sort command
supports -V option (version-sort), would you please try:
declare -A base2ver base2file
# compare versions
# returns 0 if $1 equals to $2
# 1 if $1 is newer than $2
# -1 if $1 is older than $2
vercomp() {
if [[ $1 = $2 ]]; then
echo 0
else
newer=$(echo -e "$1\n$2" | sort -Vr | head -n 1)
if [[ $newer = $1 ]]; then
echo 1
else
echo -1
fi
fi
}
for f in Directory-1/*.txt; do
basename=${f##*/}
version=${basename##*_}
version=${version%.txt} # version number such as "2.0.0"
basename=${basename%_*} # basename such as "FileOne"
base2ver[$basename]=$version # associates basename with version number
base2file[$basename]=$f # associates basename with full filename
done
for f in Directory-2/*.txt; do
basename=${f##*/}
version=${basename##*_}
version=${version%.txt}
basename=${basename%_*}
if [[ -n ${base2ver[$basename]} ]] && (( $(vercomp "${base2ver[$basename]}" "$version") > 0 )); then
# echo "${base2file[$basename]} is newer than $f"
rm -- "$f"
cp -p -- "${base2file[$basename]}" Directory-2
fi
done