Photo by Stefan Steinbauer on Unsplash
Unlocking the Secrets of the .git Folder: Understanding the Inner Workings of Git
Git Series: https://makereading.com/series/git
PermalinkIntroduction
The .git
folder is a hidden folder that is created when you initialize a new Git repository. It contains all the information and files that Git needs to keep track of the changes in your codebase.
PermalinkHow it is created?
When you create a new Git repository, either by using the "git init
" command or by cloning an existing repository, a new .git folder is created in the root directory of your project. Inside this folder, you will find several other folders and files that are used by Git to keep track of your codebase.
PermalinkAnatomy of .git
- OBJECTS Folder
The first folder that you will see inside the .git folder is the "objects" folder. This folder contains all the individual files that make up your codebase, as well as all the commits that have been made to the repository.
Each file is stored as a separate object, with a unique name (7cf580174ff116af837ae2be18ab098264f819 - in our case) that is determined by the content of the file.
REFS Folder
The next folder that you will see inside the .git folder is the "refs" folder. This folder contains references to the different branches and tags that exist in the repository. A reference is simply a pointer to a specific commit in the repository.
For example, the "HEAD" reference points to the commit that is currently checked out, while the "master" reference points to the commit that is currently on the master branch.
The "HEAD" file is a special file that points to the current branch that you are working on. It is used by Git to determine which branch you are currently on, and which branch you should be committing your changes to.
In the above image, we can see the last commit id - a19c20ee87736e1891c52a53928d2166b2f7abd3 (generated using
git log --format="%H" -n 1
) which is the same as the content of themaster file which HEAD points to.
CONFIG File
The "config" file is a plain text file that contains various configuration settings for the repository. This includes things like the name of the repository, the email address of the person who created it, and various other settings.
Description File
The "description" file is a plain text file that contains a short description of the repository. This file is not used by Git itself, but it can be useful for providing a brief overview of the project for other people who might be working on it.
INDEX File
The "index" file is also known as the "staging area" or "cache". It is a binary file that contains a list of all the files that are currently being tracked by Git.
It also keeps track of the changes that have been made to each file and keeps a copy of the file's content in a compressed format. When you run the "
git add
" command, the changes you made to the file are added to the index, and when you run the "git commit
" command, the changes in the index are saved as a new commit in the "objects" folder.LOGS Folder
The "logs" folder contains a record of all the commits that have been made to the repository. Each file in this folder corresponds to a specific branch or tag and contains a list of all the commits that have been made to that branch or tag.
The tree structure of logs folder
Content of the master file inside logs,
HOOKS Folder
Finally, the "hooks" folder contains scripts that are run at specific points in the Git workflow. These scripts can be used to automate certain tasks, such as running tests or deploying code.
PermalinkConclusion
Actually, it's worth noting that the .git folder is not meant to be edited or modified by hand. Making changes directly to files in the .git folder can cause issues with the repository and lead to data loss.
Instead, Git provides a set of commands and tools that should be used to make changes to the repository.
Additionally, the .git folder is local to your machine and it is not pushed to the remote repository unless you use the command "git push --all
" which is not recommended. This means that if you delete the .git folder, you will lose the entire history of your repository and will not be able to push or pull changes from the remote repository.
In general, it's best to let Git manage the .git folder and only make changes to the repository through the use of Git commands and tools. By understanding the role of the .git folder and the contents within it, you can better understand how Git works and how to troubleshoot any issues that may arise.
In conclusion, the .git folder is an important part of a Git repository, it contains all the information and files that Git needs to keep track of the changes in your codebase. Understanding the contents and role of the .git folder can be helpful in understanding and troubleshooting Git-related issues, but it's important to keep in mind that the .git folder should not be modified by hand and it is local to your machine. Always use the Git commands and tools to make changes to the repository.