Shell Script – How to Move Files Based on File Name Expression

bashshellshell-script

I want to achieve the following using a shell script. When a script is called with a file as a parameter, it should move the file based on a portion of its name.

For example,
"Car insurance quotations_zz21.pdf" to sort into 21.Car insurance (a sub-folder of FilingCab)
"2012-09-01 Home insurance quote_zz20.pdf" to sort into 20.Home insurance (a sub-folder of FilingCab)

Logically I think it should read something like this. I did programming long long time ago, so I think have the algorithm, but do not have the commands or the syntax.

Thanks a bunch for help!

FileToMove = $1
FolderNo = (The number after zz and before a .)
ParentFolder = (~/FilingCab)
FolderList = (List of all folders in ParentFolder) 
TargetFolder = (Folder among FolderList that begins with FolderNo) - use grep?

if TargetFolder <> not empty
         cd ParentFolder
         mv FileToMove to TargetFolder
end with success
else
         do nothing
endif

end script

Best Answer

Try something like this:

#! /bin/bash

# Config variable(s)
ParentFolder="~/FilingCab"

# arg processing (minimalist :)
FileToMove="$1"

# use sed to extract folder number from filename.
FolderNo=$(echo "$FileToMove" | sed -r -e 's/.*zz([0-9]+)\.pdf/\1/')

# use find to search for subdirectories of parent folder that begin
# with the folder no followed by a '.'
TargetFolder=$(find "$ParentFolder" -maxdepth 1 -type -a -d -name "${FolderNo}.*")

NumFolders=$(echo "$TargetFolder" | wc -l)

if [ "$NumFolders" -eq 1 ] ; then 
 mv "$ParentFolder/$FileToMove" "$TargetFolder/" 
else
  echo "Error: $NumFolders beginning with "$FolderNo." found" >&2
  exit 1
fi

Note the double-quotes around all the variable names. It's always the safe/correct thing to do but in your case it's essential because the filenames and directory names you gave as examples have space characters in them.

The -maxdepth 1 in the find command only searches for direct subdirectories of $ParentFolder (i.e. ignores subdirs of subdirs). If that's not what you meant, just remove that part. This find searches for any subdirectories of $ParentFolder that begin with $FolderNo.

I'm not entirely sure what you mean by "if TargetFolder is not equal to not empty", i'm assuming you meant "is the string $TargetFolder non-empty". Ordinarily, I'd check if $TargetFolder existed and was a directory but since we're getting the directory name from a find -type d, it can only be empty or a directory. or maybe more if there's more than one beginning with "$FolderNo."

I think it's better to check if we get one and exactly one result from the find. Any other value is an error, and we can't move the file. 0 means no matching folders found. 2 or more means more than one folder beginning with "$FolderNo." was found.

The warning msg to stderr is optional. so is the exit 1, but recommended. It allows you to call this script from another script and check whether it was successful or not.

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Bash – while using ‘$?’ expression in bash script

You have an extra space between status and the =. Bash variable assignments need to have no space between the name and the = sign:

status='echo $?'

What you've written is calling the status command with the single argument =' echo $?'.

All of that said, I think that what you probably want to write is:

status=$?

That stores the value of $? into the status variable.

If your real code is a little more complicated and you want to run a command and save the value, use either of these:

status=`echo "$?"`
status=$(echo "$?")

These use command substitution to access the output of a command.

Shell Script – Sort Files into Multiple Directories Based on Filename

As already noted, the short answer is "yes".

The long answer is: You can do it with a bash script that uses awk to extract the filename elements you want to base your directory structure on. It could look something like this (where more emphasis is placed on readability than "one-liner" compactness).

#!/bin/bash


for FILE in p-*
do
    if [[ ! -f $FILE ]]; then continue; fi

    LVL1="$(awk '{match($1,"^p-([[:digit:]]+)_[[:print:]]*",fields); print fields[1]}' <<< $FILE)"
    LVL2="$(awk '{match($1,"^p-([[:digit:]]+)_n-([[:digit:]]+)_[[:print:]]*",fields); print fields[2]}' <<< $FILE)"

    echo "move $FILE to p-$LVL1/n-$LVL2"
    if [[ ! -d "p-$LVL1" ]]
    then
    mkdir "p-$LVL1"
    fi

    if [[ ! -d "p-$LVL1/n-$LVL2" ]]
    then
    mkdir "p-$LVL1/n-$LVL2"
    fi

    mv $FILE "p-$LVL1/n-$LVL2"
done

To explain:

We perform a loop over all files starting with "p-" in the current directory.
The first instruction in the loop ensures that the file exists and is a workaround for empty directories (the reason why this is necessary is that on this forum, you will always be told not to parse the output of ls, so something like FILES=$(ls p-*); for FILE in $FILES; do ... would be considered a no-go).
Then, we extract the numerals between p- and _n needed to generate the first level of your directory structure using awk (as you suspected, with regular expressions), the same for the numerals between n- and _a for the second level. The idea is to use the match function which not only looks for the place where the specified regular expression occurs in your input, but also gives you the "completed" value of all elements enclosed in round brackets ( ... ) in the array "fields".
Third, we check if the directories for the first and second level of your intended directory structure already exist. If not, we create them.
Last, we move the file to the target directory.

For more information, have a look at the Advanced bash scripting guide and the GNU Awk Users Guide.

Once you are more firm in scripting and regular expressions, you can make this much more compact; in the above script, for example, the generation of the directory/subdirectory path could easily be contracted to just one awk call.

For one, since the directory names are actually p-<number> and n-<number>, the same as in your filename, we could have let awk do the work to extract these characters for us, too, by writing match($1,"(^p-[[:digit:]]+)_(n-[[:digit:]]+)_[[:print:]]*",fields)
We can further offload work to awk by having it generate the directory-subdirectory path at the same time with a suitable argument of print:

awk '{match($1,"(^p-[[:digit:]]+)_(n-[[:digit:]]+)_[[:print:]]*",fields); print fields[1] "/" fields[2]}'

would readily yield (e.g.) p-12345/n-384 for file p-12345_n-384_a-583.pdf. If we combine that with the usage of mkdir -p as indicated by @wurtel, the script could look like

for FILE in p-*
do
    if [[ ! -f $FILE ]]; then continue; fi

    TARGET="$(awk '{match($1,"(^p-[[:digit:]]+)_(n-[[:digit:]]+)_[[:print:]]*",fields); print fields[1] "/" fields[2]}' <<< $FILE)"
    echo "move $FILE to $TARGET"

    mkdir -p "$TARGET"
    mv $FILE $TARGET
done

Best Answer

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