Add: changer auteurs commits

content/posts/changer-auteurs-commit.en.md

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+date = '2025-10-20T00:01:00+02:00'
+draft = true
+title = "Rewriting Git History: Changing Commit Authors"
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+
+Recently, I took a bit of a turn — new direction, new mindset, new goals. I dropped some services, cut a few habits, and doubled down on others. It’s not the first time — and definitely won’t be the last. Every time, same story: new alias, maybe a new URL, and off we go again.
+
+This time, though, I wanted to change the authors of my Git commits — just to avoid looking like I’ve got multiple personalities committing to the same repo. You know, before someone starts suspecting schizophrenia.
+
+Case 1: Replace all authors
+
+If you want to replace every single author with one consistent identity:
+
+```bash
+git filter-repo --commit-callback '
+commit.author_name = b"Votre Nom"
+commit.author_email = b"email@exemple.com"
+commit.committer_name = b"Votre Nom"
+commit.committer_email = b"email@exemple.com"
+' --force
+```
+
+This command walks through every commit and replaces both the author and committer.
+
+Important notes:
+	•	Values must be Python bytes (b"...")
+	•	The --force flag is required to apply the changes (no confirmation prompt)
+	•	This operation recreates all commits, so their SHA hashes change
+    
+Case 2: Replace a specific author
+
+If your repo has multiple authors but you only want to fix one of them, add a condition:
+
+```bash
+git filter-repo --commit-callback '
+if commit.author_name == b"Ancien Nom":
+    commit.author_name = b"Nouveau Nom"
+    commit.author_email = b"nouvel@email.com"
+    commit.committer_name = b"Nouveau Nom"
+    commit.committer_email = b"nouvel@email.com"
+' --force
+```
+
+Case 3: Replace only names or only emails
+
+You can also apply more granular transformations.
+For example, replace names only:
+
+```bash
+git filter-repo --name-callback 'return b"Nouveau Nom"' --force
+```
+
+Or replace emails only:
+
+```bash
+git filter-repo --email-callback 'return b"nouvel@email.com"' --force
+```
+
+Full workflow: a practical example
+
+Let’s say your commits are under “Tartanpion old@email.com” and you want to fix that mess.
+
+1. Check current authors
+
+Before doing anything, list your contributors:
+
+```bash
+git log --format='%an <%ae>' | sort | uniq
+```
+
+That’ll show all unique authors in the repo.
+
+
+### 2. Apply the filter
+
+```bash
+git filter-repo --commit-callback '
+if commit.author_name == b"Tartanpion":
+    commit.author_name = b"DuN0Z"
+    commit.author_email = b"dunoz@porzh.me"
+    commit.committer_name = b"DuN0Z"
+    commit.committer_email = b"dunoz@porzh.me"
+' --force
+```
+
+### 3. Verify the result
+
+```bash
+git log --format='%an <%ae>' | sort | uniq
+```
+
+Authors should now all show the updated identity.
+
+### 4. Check repo integrity
+
+```bash
+git fsck
+```
+
+This ensures the repository is still consistent.
+
+### 5. Force push the new history
+
+Since you’ve rewritten the history, you’ll need to force push it to the remote:
+
+```bash
+git push origin master --force
+```
+
+**Warning :** --force overwrites history on the remote.
+Make sure that’s okay for your team — or in my case, it’s all personal stuff, so… who cares.
+
+## Common pitfalls
+
+Refusing to run without --force:
+Git will refuse to rewrite history unless you explicitly allow it. Use --force consciously.
+
+Old references sticking around:
+After filtering, Git keeps old references under .git/refs/original/. You can safely remove them:
+
+
+```bash
+rm -rf .git/refs/original/
+git reflog expire --expire=now --all
+git gc --prune=now
+```
+
+Collaborators affected:
+If others work on this repo, they’ll need to re-clone or rebase their branches.
+Coordinate… or don’t — in my case, nobody else touches these repos. Like this blog, actually — I love throwing digital messages in bottles.
+
+## After the force push
+
+Once pushed, the remote will now reflect your new commits.
+Old commits will stick around temporarily (until garbage collection), but they’ll fade away soon enough.
+
+If someone else cloned the old history:
+
+
+```bash
+git fetch origin
+git reset --hard origin/master
+```
+
+## Conclusion
+
+Rewriting Git history with git filter-repo is powerful — and should be used wisely.
+It’s great for fixing author mistakes, cleaning up legacy commits, or prepping a repo before publishing it publicly. Always double-check, and if in doubt, test on a copy first.
+
+If you want to avoid this situation in the future, make sure your Git identity is configured properly:
+
+```bash
+git config --global user.name "Votre Nom"
+git config --global user.email "email@exemple.com"
+```
+This is especially true if you use multiple machines — it gets messy fast.
+Or better yet, put everything under NixOS and import the same git.nix config everywhere.
+You know what caused my issue? The Mac.
+Classic karma.