Remove a file from a older commit without affecting any other commits in gitlab

Question

I am using the gitlab repository for uploading my code files. I have made more than 500 commits. My repo size was upto 540 mb. I want to minimize the size of the repo by deleting unwanted files in the repo.

Somehow i managed and deleted the files in my local. Now my current file size is 10 mb in the local. I pushed it and it was good. Eventhough it shows 540mb. I came to know the previous commit files holds the storage. There is a zip file with a size of 400 mb which is in one of my older commit.

I found the commit by using the shell script. I want to delete the zip file in the commit. But it shows "You can only delete files when you are on the branch" in the gitlab webui. In the terminal, I found the command git rm <file_name> to remove the file. I got the file path from the commit. But I don't know how to use it on a particular commit. It holds some important files. I don't wanna play with it.

My question is: how do I remove a certain file in a particular commit in gitlab without affecting any other commits? I tried Stack Overflow and found some answers to delete the file in previous commit but not in the older commit. Help me with some solutions.

Answer 1

The short answer is grim : you can't.

That is, you could modify a commit in the past, but it would modify every commit down the line so it doesn't check the "without affecting anyother commits" part.

Take a look at git filter-branch to have an idea of what tools are at your disposal to change history, but be aware that's quite a heavy operation.

Answer 2

It's no possible to delete the file without affect commit history.

To delete the file in the history, you can use git built-in git-filter-branch or third party bfg-repo-cleaner

Refer to i-want-to-remove-a-large-file-from-ever-existing-in-repo-history of Github: git-flight-rules

recommended-technique-use-third-party-bfg

(master)$ git rm path/to/filetoremove
(master)$ git commit -m "Commit removing filetoremove"
(master)$ java -jar ~/Downloads/bfg.jar --delete-files filetoremove

built-in-technique-use-git-filter-branch

(master)$ git filter-branch --force --index-filter 'git rm --cached --ignore-unmatch filepattern' --prune-empty --tag-name-filter cat -- --all