Using Git and GitLab: Your first steps. Maurício

Transcription

1 Using Git and GitLab: Your first steps Maurício

2 How do you store your files?

3 We used to do like this before But now we do it in a different (and much better) way!

4 We need clear history of changes

5 Even at low level!

6 We need discussions around our changes

7 We need lists of issues to solve or improve.

8 What we are gonna use? Git: Version control system that tracks the changes in our software source code. GitHub/GitLab: They are hosting services, and offer interesting features on top of Git, such as access control, issue tracking, code reviews, etc. In this course, we are gonna use Git and GitLab*.

9 Are they popular? Git is the standard tool for source code versioning in industry. GitHub is the largest social coding platform we have. You have to practice it to master it.

10 You start by cloning a repo Central

11 clone Central

12 Everyone has the same repository. Central

13 Core ideas: working and remote We call your local repository, a working or local version. We call any repository that is in an external place, remote repository. Commonly, our remote repositories are stored in GitLab/GitHub. We often call our main remote repository, origin.

14 Updates: A.Py Creates: B.Py Deletes: C.py Dev 1 just created a new commit. Central

15 Core ideas: Commit Git keeps track of snapshots of your code. Basically, you tell Git when to take a snapshot of the current version of your code. You can later visit any snapshot you took. We often call these snapshots, commits. It is also often used as a verb and as a noun: I will commit my changes now. Did you see my latest commit?

16 Dev 1 just created a new snapshot. push Central

17 Dev 1 just created a new snapshot. push Central

18 Core ideas: Push When you want to update a remote reference with what you have in your machine. Also used as a verb: I m gonna push my changes right now.

19 Core ideas: Head commit Git stores your commits as a sequence of snapshots/commits. Each commit has a pointer to its parent. We call head commit the most recent commit of your repository.

20 Other devs still don t have it Central

21 Other devs still don t have it pull Central

22 Other devs still don t have it pull Central

23 Core ideas: Pull When you want to update your machine with what s in a remote server.. Also used as a verb: I m gonna pull all your changes right now.

24 People work in parallel (see dev 3) Central

25 People work in parallel (see dev 3) Central push

26 You can t simply ask GitLab to merge for you! ERROR: We have different snapshots!! Central

27 pull Central

28 pull Central

29 Merge commit Central

30 Core idea: Merge When we combine the changes between your repository and the remote repository. It creates an explicit merge commit. Also see git rebase if you are curious about different ways of merging:

31 push Central

32 Central

33 pull Central

34 Central

35 It is showtime!

36 Branches and PRs We often enjoy having our master line (branch) only with changes that we approved. This means we need to maintain two lines: The master one The one we are currently working on.

37 Dev 1 has its own branch feature-1 Central

38 You can store it in your server as well push feature-1 Central

39 Central feature-1

40 Any dev can get it if they want pull feature-1 Central feature-1

41 Any dev can get it if they want Central feature-1

42 Core idea: Branch See a branch as a sequence of commits. They start somewhere and they end somewhere. There might be different branches with more or less commits, with different commits, etc. merge Right now, we: have master branch, with all the 6 commits. We may have a feature-1 branch only with the two green commits.

43 Pull Request Before merging our changes to master, we can ask for the opinion of someone else. Only after some reviewing is that we merge them. git merge branch-we-wanna-merge GitHub and GitLab help us with this.

44 We can use it to discuss and improve.

45 It is showtime!

46 Git has lots of more features! You never stop learning Git. Get familiar/proficient with the Git basics: git add, git commit, git push, git pull, git branch, merge vs rebase, git ignore. Get familiar with GitLab/GitHub: pull requests. Get started in the lab: /activities/get-to-know-git.html. From now on, all your source code should be stored in Git!!

47 License You can use and share any of my material (lecture slides, website). You always have to give credits to the original author. You agree not to sell it or make profit in any way with this. Material that I refer has its own license. Please check it out.

48 References Rock and roll show, by Ryan Loughlin: Female engineer by GDJ: Git, GitHub, and GitLab are registered trademarks.