Read files from directory and organize them by extentsion into corresponding folders

Question

I'm trying to create a bash function script that will allow me to create multiple directories with the names below. I'm also trying to organize files by extension into their corresponding folders (i.e. .jpg into pictures, .doc into documents, .gif into media, etc). The first part is fine it's the second half after the directories are made that confuses me.

    #!/bin/bash
    echo "Creating directory categories"

    function make_folder 
    {
        cd -; cd content; sudo mkdir ./$1
    }

    make_folder "documents"
    make_folder "other"
    make_folder "pictures"
    make_folder "media"

    echo "Directories have been made"; cd -
    exit

    ext="${filename##*.}" #set var ext to extension of files

    find ./random -name | #find and list all files in random folder
                          #pipe results of find into if statement

    if ext == ["jpg"; "jpeg"; "png"] #move ".jpg", etc to new destination
         then
           mv /path/to/source /path/to/destination

    elif ext == [".gif"; ".mov"] #move ".gif", etc to new destination 
         then
           mv /path/to/source /path/to/destination
    else                         #move other files into to new destination
           mv /path/to/source /path/to/destination
    fi

Answer 1

From the top of my head I would use the 'case' statement in the end.

i.e.

case "$FILE" in
    *.jpg|*.jpeg)
        mv "$FILE" to where you want it
        ;;
    *.gif|*.mov)
        mv "$FILE" to where you want it
        ;;
    *)
        echo "Unmanaged file type: $FILE, skipping"
        ;;
 esac

...however you need to wrap it in a loop container, and you seen determined to use find, and then it would perhaps be appropriate with;

 find <your stuff> | 
     while read FILE
     do
         ...case statement goes here
     done

Just my $0.02

Cheers! / Daniel

Answer 2

Your make_folder function is needlessly complicated: all these current directory changes are just making your life more complicated. On top of that, you don't need sudo: why would you create the directories as root? Just call mkdir.

mkdir documents other pictures media

If you want the script to work even if the directories already exist, use mkdir -p:

mkdir -p documents other pictures media

If you want to use find , don't make it print the names and then parse them. Make find execute the code you want with -exec. To do more than invoke a simple program, invoke a shell. With <code>sh -c '<em>shell code</em>', the next argument to sh after the shell code is available in the shell code as $0. Always put double quotes around varaiable substitutions. In the shell snippet, the natural way to discriminate by extension is with a case construct on the file name. I use the parameter expansion construct ${0##*/} to get the base name of the file (with everything up to the last slash removed). The test [ -e "$destination_file" ] tests if the destination file already exists, to avoid overwriting a file by the same name that was moved from a different directory.

find random -exec sh -c '
  case "$0" in
    *.gif|*.png|*.jpg) destination_directory=pictures;;
    …
    *) destination_directory=other;;
  esac
  destination_file="$destination_directory/${0##*/}"
  if [ -e "$destination_file" ]; then mv "$0" "$destination_file"; fi
' {} \;

An alternative approach, which may be a little slower if you have a huge amount of files but is a lot simpler to write, is to copy the files destination by destination. On Linux, thanks to GNU utilities, it's as simple as

find random \( -name '*.gif' -o -name '*.png' -o -name '*.jpg' \) -exec mv -n -t pictures {} +

and likewise for other target directories. Using + rather than ; at the end of find -exec speeds things up a little by invoking mv in batches.

But for what you're doing, in fact, in bash or zsh, you don't need find. Use the ** wildcard for recursive directory traversal.

shopt -s globstar # necessary in bash to enable **
mv -n random/**/*.gif random/**/*.png random/**/*.jpg pictures/

Note that I assume that you want to put all the files directly under the target directories. If you want to reproduce the directory hierarchy, that's a different matter, and different tools would be appropriate.