Viewing the history with gitk

We saw earlier how we can view the history (the DAG) and visualize it by using git log. However, as the history grows, the terminal representation of the history can be a bit cumbersome to navigate. Fortunately, there are a lot of graphical tools in Git, one of them being gitk, which works on multiple platforms (Linux, Mac, and Windows).

This recipe will show you how to get started with gitk.

Getting ready

Make sure you have gitk installed:

$ which gitk
/usr/local/bin/gitk

If nothing shows up, then gitk is not installed on your system, or at least is not available on your $PATH.

Change the directory to the Git-Version-Control-Cookbook-Second-Edition repository from the objects and DAG examples. Make sure the master branch is checked out and pointing to 13dcad:

$ git checkout master && git reset --hard 13dcad

How to do it...

In the repository, run gitk --all & to bring up the gitk interface. You can also specify the commit range or branches you want, just as you did with git log (or provide --all to see everything):

$ gitk --all &

Gitk shows the commit history of the repository:

How it works...

Gitk parses the information for every commit and the objects attached to it to provide an easy graphical information screen that shows a graph of the history, author, and timestamp for each commit. In the bottom half is the result of selecting a commit. The commit message and the patches for each file that has changed . Moreover, a list of files that have been changed is displayed to the right.

Though very lightweight and fast, gitk is a very powerful tool. There are many different context menus that appear after the user clicks on a commit, a branch, or a tag in the history view. You can create and delete branches, revert and cherry-pick commits, diff selected commits, and much more.

There's more...

From the interface, you can perform a find and search operation. Find looks through the history and Search looks through the information displayed in the lower half of gitk for the commit that is currently highlighted.