22. Inside Git: .Git directory
- To learn about Git directory structure
It is time to do some research. Starting from the project’s root directory...
ls -C .git
$ ls -C .git COMMIT_EDITMSG MERGE_RR config hooks info objects rr-cache HEAD ORIG_HEAD description index logs refs
This is a special folder where all the git stuff is. Let us explore the directory.
02 Object Database
ls -C .git/objects
$ ls -C .git/objects 09 24 28 45 59 6a 77 80 8c 97 af c4 e7 info 11 27 43 56 69 6b 78 84 91 9c b5 e4 fa pack
You should see a lot of folders named with two characters. The first two letters sha1 hash of the object stored in git are the directory names.
03 Inquire the database objects
ls -C .git/objects/<dir>
$ ls -C .git/objects/09 6b74c56bfc6b40e754fc0725b8c70b2038b91e 9fb6f9d3a104feb32fcac22354c4d0e8a182c1
Let us look at one of the folders named with two characters. There should be files with names of 38 characters. These files contain objects stored in git. They are compressed and encrypted, so it’s impossible to view their content directly. Let us have a better look at Git directory
04 Config File
$ cat .git/config [core] repositoryformatversion = 0 filemode = true bare = false logallrefupdates = true ignorecase = true [user] name = Alexander Shvets email = email@example.com
This configuration file is created for each individual project. At least in this project, entries in this file will overwrite the entries in the
.gitconfig file of your main directory.
05 Branches and tags
ls .git/refs ls .git/refs/heads ls .git/refs/tags cat .git/refs/tags/v1
$ ls .git/refs heads tags $ ls .git/refs/heads master $ ls .git/refs/tags v1 v1-beta $ cat .git/refs/tags/v1 fa3c1411aa09441695a9e645d4371e8d749da1dc
Files in tags subdirectory should be familiar to you. Each file corresponds to the tag previously created using the git tag command. Its content is nothing but a hash commit attached to the tag.
The heads folder is almost identical and is used not for tags, but branches. At the moment we have only one branch, and everything you see in this folder is a master branch.
06 HEAD File
$ cat .git/HEAD ref: refs/heads/master
There is a reference to the current branch in the HEAD file. At the moment it must be the master branch.