How to substitute text from files in git history?

Tom picture Tom · Nov 5, 2010 · Viewed 16.8k times · Source

I've always used an interface based git client (smartGit) and thus don't have much experience with the git console.

However, I now face the need to substitute a string in all .txt files from history (so, not erasing the whole file but just substituting a string). I found the following command:

git filter-branch --tree-filter 'git ls-files -z "*.php" |xargs -0 perl -p -i -e "s#(PASSWORD1|PASSWORD2|PASSWORD3)#xXxXxXxXxXx#g"' -- --all

I tried this, and unfortunately noticed that while the password did get changed, all binary files got corrupted. Images, etc. would all be corrupted.

Is there a better way to do this that won't corrupt my binary files?

Thanks.

EDIT:

I got mixed up with something. The actual code that caused binary files to get corrupted was:

$ git filter-branch --tree-filter "find . -type f -exec sed -i -e 's/originalpassword/newpassword/g' {} \;"

The code at the top actually removed all files with my password strangely enough.

Answer

Roberto Tyley picture Roberto Tyley · Mar 31, 2013

I'd recommend using the BFG Repo-Cleaner, a simpler, faster alternative to git-filter-branch specifically designed for rewriting files from Git history.

You should carefully follow these steps here: https://rtyley.github.io/bfg-repo-cleaner/#usage - but the core bit is just this: download the BFG's jar (requires Java 7 or above) and run this command:

$ java -jar bfg.jar  --replace-text replacements.txt -fi *.php  my-repo.git

The replacements.txt file should contain all the substitutions you want to do, in a format like this (one entry per line - note the comments shouldn't be included):

PASSWORD1 # Replace literal string 'PASSWORD1' with '***REMOVED***' (default)
PASSWORD2==>examplePass         # replace with 'examplePass' instead
PASSWORD3==>                    # replace with the empty string
regex:password=\w+==>password=  # Replace, using a regex
regex:\r(\n)==>$1               # Replace Windows newlines with Unix newlines

Your entire repository history will be scanned, and .php files (under 1MB in size) will have the substitutions performed: any matching string (that isn't in your latest commit) will be replaced.

Full disclosure: I'm the author of the BFG Repo-Cleaner.