Gitless

A simple implementation of Git in TypeScript.

Learning resources

• What's inside .git directory
• oclif

Features to implement

• init
• add
• rm
• commit
• branch
• checkout
• diff
• remote
• fetch
• merge
• pull
• push
• status
• clone

What I learned during this project?

The .git directory

At a bare minimum, a .git repository should contain the following files and dirs:

- .git
    - objects/
    - refs/
    - HEAD
    - config

Read a blob object

Blobs are used to store file data. Blobs only store the contents of a file, not its name or permissions. All Git objects are identifiable by a 40-character SHA-1 hash, also known asthe "object hash". Example of an object hash: e88f7a929cd70b0274c4ea33b209c97fa845fdbc Each Git Blob is stored inside the .git/objects directory.

THe cat-file command

This command shows the type of an object, it's size and it's content. Example usage:

$ git cat-file -p <blob_sha>
hello world # This is the contents of the blob

Todo:

• Read the contents of the blob object file from the .git/objects directory
• Decompress the contents using Zlib
• Extract the actual "content" from the decompressed data
• Print the content to stdout