Subversion (SVN) helper bash script to list repo dirs

Finding my way around SVN. So far I’ve created a repository to hold my WordPress theme files and miscellaneous scripts. The working directories are scattered around my home dir, and I found that I wanted a way to view the structure of the repo itself. You can do this with the svn list command:

svn list --recursive file:///path/to/your/svn/repo/dir

And you’ll get a list of all your directories and files. I thought it might be nice to only see the dirs, and then furthernice to specify the depth of dirs to browse, so I cobbled together the bash script below to accomplish this. It takes the output from svn list -R and prints only items that end with a forward slash, e.g.:

svn list -R file:///home/scarpent/src/svn | svn-dirs.sh -d 2

To produce the output:

bash/
bash/nautilus-scripts/
home-bin/
web/
web/mtf/

(I also created a script that runs svn list on my local repo and pipes to svn-dirs.sh, so I don’t have to type in the file:/// URL every time.)

How does it work?

First we use getopts to parse the command line options, which in this case is only -d, which lets us specify the max depth of directories we want to list.

Next, we use read to read the output produced by svn list. (Which becomes standard in — stdin — for our script.)

I initially thought of using the bash -d test to see if an item was a file or a dir, but I quickly realized that this wouldn’t work because these aren’t real files and directories. They’re part of the virtual SVN file system. Instead, I went by the last character, which is a forward slash for directories. We use ${#inpt} to get the length of the string, $(($len - 1)) to subtract one from that length, giving us the index of the last character, and then ${inpt:$last_char_idx} to extract that last character so we can compare it to “/”.

Finally, we determine how many slashes there are in the path — and thus the depth — by using this peculiar statement:

num_slashes=$(echo $inpt | tr -cd "/" | wc -c)

Which sends the SVN path in to the translate program, using options to discard anything that isn’t a forward slash, and then counts the remaining slashes with the word count program. (I found this neat trick in the Advanced Bash-Scripting Guide, along with a lot of other interesting string handling techniques. See resources below for more…)

And now, the script!

svn-dirs.sh script

#!/bin/bash

# svn-dirs.sh
# public domain script
# by Scott Carpenter, 2007

usage="svn-dirs.sh [-d] specify the depth of dirs to list"

max_depth=99
while getopts ":d:" opt
do
        case $opt in
                d  ) max_depth=$OPTARG ;;
                \? ) echo -e $usage
                     exit 1
        esac
done
shift $(($OPTIND - 1))

if [[ $(($max_depth < 1)) -eq 1 ]]; then
	max_depth=1
fi

while read inpt
do
	len=${#inpt}
	last_char_idx=$(($len - 1))
	last_char=${inpt:$last_char_idx}

	# tr = translate, discarding non-matches
	# then use wc to count chars, giving us
	# the number of slashes
	num_slashes=$(echo $inpt | tr -cd "/" | wc -c)	

	if [[ "$last_char" = "/" && $(($num_slashes <= $max_depth)) -eq 1 ]]; then
		echo "$inpt"
	fi
done

And that’s that. I hope you find this useful for browsing your SVN repository and getting an overview of what you have stashed away in there.

Resources

Buy @ Amazon
or Free Online

Buy @ Amazon

• Version Control with Subversion is an excellent O’Reilly book by Ben Collins-Sussman, Brian W. Fitzpatrick, and C. Michael Pilato. There is a free version online, or you can click on one of the Amazon links here if you want to buy a hard copy and cut me in on a share of the loot.

• Learning the bash Shell is another good O’Reilly book by Cameron Newham and Bill Rosenblatt. Even with all the good bash info available for free on the Net, I still like to have books like this to guide me through things. Again if you buy through one of my Amazon links, I’ll get a small kickback on the purchase price.

• The Advanced Bash-Scripting Guide by Mendel Cooper is one of those great free resources. The tag line is “An in-depth exploration of the art of shell scripting,” and it appears to be full of useful knowledge and techniques.

Related: SVN Nautilus Script Helpers