从特定提交开始将现有项目添加到GitHub

Question

A local project is ready to be pushed to a GitHub repository. The GitHub repository was initialized WITHOUT README and license.

From commit C1 to Cn - C1 is the first/initial commit, and Cn is the n -th/latest commit -, the local project contains sensitive. But from the commit Cn+1 onwards the sensitive data is masked.

For example, C1..Cn+3 is my currently local git repository:

C1 < C2 < C3 < .. < Cn < Cn+1 < Cn+2 < Cn+3

I want to push the commit Cn+1 and onwards. So, the remote repository should have C1'..C3'

C1 < C2 < C3 < .. < Cn < Cn+1 < Cn+2 < Cn+3
                         C1' < C2' < C3'

Where C1' in the remote repository is Cn+1 in my local repository.

How to add the local project to GitHub starting at the commit Cn+1 ? The following push should ignore the commits C1..Cn .

I've already tried git push origin <sha>:<branch> but it push the whole project. Rebase didn't quite fit for me either.

Answer 1

There are a few ways to do what you want, but the most important point is this: you won't be able to use the Github repo seamlessly . So if your intention is to use it as a way to share new commits or fetch contributions from other people and then put them back on your original history, that's not going to be possible in the traditional way.

Making a new repository

The simplest way is to just copy your working tree with all your files in it, in the repository state you want, init that as a new git repo, make a single initial commit, and then push everything to Github.

You'll be able to use the new repo as normal, and nothing of the original history will be shared or preserved.

Making a public branch

Another option is to make a new branch on the current repo as an orphan ie a branch with a no root, and do the same thing as making a new repo above - copy files, make a new starting commit, and push this branch to Github.

You'll then be able to share and fetch changes made on the public repository, but getting them back onto your main branch will be more difficult - you can use one-way merges into the private branch, and make all edits on the public branch only, which will keep your history without sharing it.

You'll need to be very careful with merge direction if you want to take this approach, though. If you push a merge in the wrong direction, the history will become public.

For more info, see this question: Push a branch of a git repo to a new remote (github), hiding its history

Addendum: why isn't this possible?

Ben Jackson explains it in the answers to the above question: a commit's hash is partly based on every commit preceding it in the repo. Since what you want to do would publicly create a new commit (without a parent), git will refuse to treat it as though it was really your old commit, because the hashes won't match.