bash script git filter-branch change committer and author email

x-replace-git-email.sh

#!/bin/sh

echo "CHOOSE OPTION"
echo "[0] HEAD / [1] BRANCH NAME"
read REPLACE_EMAIL_OPTION

if [[ $REPLACE_EMAIL_OPTION = 0 ]]
then 
    GIT_BRANCH="HEAD"
else 
    echo "PROVIDE BRANCH NAME:"
    read GIT_BRANCH
fi

echo "$REPLACE_EMAIL_OPTION"
echo "$GIT_BRANCH"
git filter-branch -f --env-filter '
# replace domain.com with your <domain>
GIT_EMAIL_PATTERN="^(.*)@.*\.domain\.com$"

if [[ $GIT_COMMITTER_EMAIL =~ $GIT_EMAIL_PATTERN ]] || [[ $GIT_AUTHOR_EMAIL =~ $GIT_EMAIL_PATTERN  ]];
then
    echo "WE HAVE A MATCH"
    export GIT_COMMITTER_EMAIL="${BASH_REMATCH[1]}@domain.com"
    export GIT_AUTHOR_EMAIL="${BASH_REMATCH[1]}@domain.com"
    echo "$GIT_COMMITTER_EMAIL"
else 
    echo "NOPE"
fi
#echo "${BASH_REMATCH[0]}"
#echo "$GIT_COMMITTER_EMAIL"
' $GIT_BRANCH

if [[ $GIT_COMMITTER_EMAIL =~ $GIT_EMAIL_PATTERN ]]

if RegEx matches, then the capture groups are available in BASH_REMATCH[1], BASH_REMATCH[2], etc

read REPLACE_EMAIL_OPTION

read in a bash script waits for user input

$GIT_BRANCH git filter-branch requires the final param be the branch to apply the history rewrite, or HEAD for convenience