Bash : Verify empty folder before ls -A - bash

Question

I'm starting to study some sh implementations and im running into some troubles when trying to do some actions with files inside some folders.
Here is the scenario:
I have a list of TXT files inside two different subfolders :
├── Folder A
├── randomFile1.txt
├── randomFile2.txt
├── Folder B
├── File1.txt
├── Folder C
├── File2.txt
And depending of the folder that the file resides in, i should take an specify action.
obs1 : The files from folderA should not be processed.
basicaly i tried two different aprroachs:
first one :
files_b="$incoming/$origin"/FolderB/*.txt
files_c="$incoming/$origin"/FolderC/*.txt
if [ "$(ls -A $files_b)" ]; then
for file in $files_b
do
#take action
done
else
echo -e "\033[1;33mWarning: No files\033[0m"
fi
if [ "$(ls -A $files_c)" ]; then
for file in $files_c
do
#take action
done
else
echo -e "\033[1;33mWarning: No files\033[0m"
fi
the problem for this one is that when i run the command ls -A if one of the folders (B or C) is empty, it throws an error because of the " *.txt " in the end of the path.
The second :
path="$incoming/$origin"/*.txt
find $path -type f -name "*.txt" | while read txt; do
for file in $txt
do
name=$(basename "$file")
dir=$(basename $(dirname $file))
if [ "$dir" == FolderB]; then
# Do something to files"
elif [ "$dir" == FolderC]; then
# Do something to files"
fi
done
done
For that approach the problem is that i'm picking the files from folder A and i dont want that (because it will decrease performance due to "if" statements), and i dont know how to verify if the folder is empty using the find command.
Can annyone help me?
Thank you all.

Answer 1

I would write the code like this:
No unquoted parameter expansions
Don't use ls to check if the directory is empty
Use printf instead of echo.
# You cannot safely expand a parameter so that it does file globbing
# but does *not* to word-splitting. Put the glob directly in the loop
# or use an array.
shopt -s nullglob
found=
for file in "$incoming/$origin"/FolderB/*.txt; do
do
found=1
#take action
done
if [ "$found" ]; then
printf "\033[1;33mWarning: No files\033[0m\n"
fi

Answer 2

In the first solution you can simply hide the error messages.
if [ "$(ls -A $files_b 2>/dev/null)" ]; then
In the second solution, start find at the subdirectories instead of the parent directory:
path="$incoming/$origin/FolderA $incoming/$origin/FolderB"

Answer 3

I think using find should be better
files_b="${incoming}/${origin}/FolderB"
files_c="${incoming}/${origin}/FolderC"
find files_b -name "*.txt" -exec action1 {} \;
find files_b -name "*.txt" -exec action2 {} \;
or even just find
find "${incoming}/${origin}/FolderB" -name "*.txt" -exec action1 {} \;
find "${incoming}/${origin}/FolderC" -name "*.txt" -exec action2 {} \;
of course you should think about your action, but you can make function or separate script which accept file name(s)