Replace text, e.g. secrets, in all files in all git commits using `git filter-branch` and `sed`.

README.md

Replace text, e.g. secrets, in all files in all git commits using git filter-branch and sed.

a. Download replace-text.sh

b. Clone the gist repo in the same directory as replace-text.sh

• using SSH url:

  1. git clone git@gist.github.com:<reponame (hash)>

• using HTTPS url:

  1. git clone https://gist.github.com/<username>/<reponame (hash)>
  2. git remote set-url --add origin git@gist.github.com:<reponame (hash)>
  3. git remote set-url --delete origin https://gist.github.com/<username>/<reponame (hash)>

c. cd into the gist repo directory

d. run replace-text.sh on all commits

• git filter-branch -f --tree-filter 'bash ../replace-text.sh <string> <my_string>' -- --all

e. restore dates

• git filter-branch -f --env-filter 'export GIT_COMMITTER_DATE="$GIT_AUTHOR_DATE"'

f. Optional: remove dangling commits

1. git reflog expire --expire-unreachable=now --all
2. git gc --prune=now

g. Force push to remote repo

1. git push -f

replace-text.sh

function echo() {
  builtin echo ${GIT_COMMIT:0:6}: "$@"
}

builtin echo
echo replacing "\"$1\"" to "\"$2\""

for f in $(git ls-tree --full-tree -r --name-only $GIT_COMMIT); do
  echo saving modification timestamp of "$f"
  touch -r "$f" "$f".timestamp

  echo modifying "$f"
  sed -i "s/$1/$2/g" "$f"
  
  echo restoring original modification timestamp of "$f"
  touch -r "$f".timestamp "$f"
  
  echo removing "$f".timestamp
  rm "$f".timestamp
done

builtin echo