Repository split and history cleaning for OUDS iOS, why and how

[pylapp]

Until end of April, the OUDS iOS project has only one repository, an alone GitHub project for both the Swift package and the design system toolbox app.
However, we have hundreds of snapshots tests using swift-snapshot-testing library, and thus thousands of screenshots versioned in the project. These screenshots are very useful to make tests of the rendering of our components look and feels.

However, they increase a log the size of the repository and also increase the time of its cloning by Xcode.
Thus, it has been decided to split the repistory into two: one for the librayr, one for the demo app.

However, it remains obviously traces of the demo app folder with the screenshots for tests in the history ; that is the reason why BFG Repo-Cleaner has been used.

The commands were simple to run, BFG Repo-Cleaner is an awesome wrapper of commands.

First, clone a mirror of the repo:

git clone --mirror [email protected]:Orange-OpenSource/ouds-ios

Then, edit the local configuration to get rid of read-only refs because of pull requests making final push fail:

git config --local --edit

and replace any rules for origin (thank you Stack Overflow):

fetch = +refs/heads/*:refs/heads/*
fetch = +refs/tags/*:refs/tags/*
fetch = +refs/change/*:refs/change/*
push = +refs/heads/*:refs/heads/*
push = +refs/tags/*:refs/tags/*
push = +refs/change/*:refs/change/*

After that, run the cleaning commands in the repository:

java -jar bfg.jar --delete-folders DesignToolbox  --no-blob-protection  ouds-ios.git

and

git reflog expire --expire=now --all && git gc --prune=now --aggressive

And the final one:

git push

However we had to disabled temporary any rulesets on the GitHub project for tags and branches to let the tool override anything.

Note

In the end it helped us to move from 354.98 Mio of downloaded objects to 137.86 Mio.
In the end, the previous repository had a size of 491 MB and now a size of 150 MB.

Caution

This operation implies for any developers to reclone the project!

Tip

BFG Repo-cleaner is as tool which deserves support!