How to create a git repository in memory?

Question

I am currently working on a flashcard application where decks created by the user act as Git repositories. When a card is created in the app, a new file is committed to the repository, when a card is changed, the file is changed, and when a card is deleted—well, you get the point.

The file format that the application saves to is a gzipped Git repository, so at no point will I ever need to write the repository to disk. How can I best handle treating decks as a Git repository in this way?

Violation

Status of flash card app? 😇 – Morion

Answer 1

Take a look at libgit2. It supports the in-memory git repository scenario and also has bindings to many languages:

https://libgit2.github.com

For example, by using rugged, the ruby binding for libgit2, you could do things like this:

a_backend = Rugged::InMemory::Backend.new(opt1: 'setting', opt2: 'setting')

repo = Rugged::Repository.init_at('repo_name', :bare, backend: a_backend)

Jarredjarrell

Thanks. I don't really understand Backend though. Why do I need one? – Violation

A backend int he context of libgit2 is just a storage mechanism for your repo. It could be in-memory storage, disk storage, database storage, cache storage, etc. You can find a detailed explanation about backends in libgit2 here – Jarredjarrell

@Jarredjarrell Do you know if that works for clone_at? I can't find in the documentation – Dillman

@Tiago I didn't test it but it looks so. Check the example in this link – Jarredjarrell

The rugged code example does not seem to work. As of Rugged 0.27.0, the README says you can create an in-memory repo using that code but the gem doesn't provide a Rugged::InMemory class. – Cruet