Directory String Replace Posted on April 19, 2013 by Dave Fowler

Yesterday I discovered that many of the old posts on the Chartio Blog used odd unicode versions of quotes that were being rendered terribly. So I needed to do a find-replace for an entire directory.

The tool for doing so is the sed command line utility, and not using it has a history of getting you ridiculed. After over an hour of reading man pages and online examples I discovered that I really hate sed. I asked around about other's experiences and it everyone that I talked to who had tried it has their own horror stories to go along with it.

Its probably a great tool, and I'm probably just too dumb to make it work for me and my odd unicode quote replacement job, but I ended up just writing/modifying a simple python script to do string replacing on a directory level. Its not a command line tool, or replacement for SED. Just a script that I found useful and am sharing for others that may as well.

 # coding: utf-8
 import os, fnmatch, sys
 def findReplace(directory, find, rep, filePattern):
     for path, dirs, files in os.walk(os.path.abspath(directory)):
         for filename in fnmatch.filter(files, filePattern):
             filepath = os.path.join(path, filename)
             with open(filepath) as f:
                 s = f.read()
             new = s.replace(find, rep)
             if new != s:
                 print "replaced in", filepath
                 with open(filepath, "w") as f:
                     f.write(new)

view raw replace.py hosted with ❤ by GitHub

It takes 4 parameters:

directory - the root directory to do the string replace in
find - the string that you would like to find
rep - the string that you would like to replace the found string with
filePattern - a pattern to match the files you would like searched (eg. '*.html' or '*.py')

The following example will replace all instances of the word *"old"* with *"new"* in files ending in *".html"* located in the ~/some/directory/ directory

findReplace('~/some/directory/', "old", "new", '*.html')