-Last updated 28-Jan-2020
Fork edits
Changes made here. More changes.
UVA Library Workshop on Introduction to Git and GitHub/GitLab.
This file exists here: https://github.com/rjp0i/git-intro (or visit here for a prettified view)
- Ricky Patterson: I am the Associate Director, Research Data Services, UVA Library
- I was a research astronomer for 20+ years here at UVA
- Everyone has a GitHub and GitLab account, and has GitHub Desktop running on their computer
- Create a repository and fork it
- Feel comfortable with git/github workflows
- Know how to get help
- git - version control software.
- GitHub - a for profit company recently purchased by Microsoft. It provides cloud-based hosting of repositories.
- GitLab - an alternative to GitHub, not owned by Microsoft (why you might want to switch). "Free software deserves free tools."
- repository (repo) - Basic unit in git: a record of all changes to specified files.
- fork - personal copy of another users repo.
- branch - a parallel version of a repo (main branch is called "master").
You can look at GitHub's Git Handbook
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To play along you will need a GitHub account --> https://github.com/
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If on mac/linux you probably already have git, but we also want GitHub Desktop.
- go to http://desktop.github.com and download.
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If on windows, the latest version of GitHub desktop http://desktop.github.com is fine for today, but it won't include the git "command line tools." They are available:
- Go to https://gitforwindows.org/ and download.
- Some background
- Work on the GitHub browser interface
- Look at the GitHub Desktop interface
- Tips on getting help
The book Computing Skills for Biologists: A Toolbox contains a useful introduction to Git with practice data and code. Members of the UVA community can access the book online. The examples, data, code, and solutions are hosted on a github repo.
- CVS (1990s) Centralized (client-server)
- SVN (2000s) Centralized (client-server)
- git (2005) Distributed. Developed by Linus Torvalds for Linux development.
- Let's walk through GitHub's Hello World Guide in the steps below.
- In a web browser, visit this repo: https://github.com/rjp0i/git-intro
- We are in the github interface:
- upper left corner: notebook icon next to rjp0i/git-intro (a repo)
- big green button on the right hand side (down a little) says "Clone or Download" (how to get the files)
- list of files (how to browse the files)
- readme.md is rendered as Markdown (github automatically shows the readme file, very handy)
https://guides.github.com/activities/hello-world/#repository
- Not so obvious, but in the upper right hand corner, click the '+' button, pull down: select 'new repository'
- name (this will be the address of the repo...)
- description
- public v private
- initialize with readme (alway say yes)
- license
https://guides.github.com/activities/hello-world/#branch
- Let's leave the master branch alone and create a new branch
- Click the drop down at the top of the file list that says branch: master.
- Type a branch name, readme-edits, into the new branch text box.
- Select the blue Create branch box or just hit “Enter” on your keyboard.
Now we have two branches: master and readme-edits
https://guides.github.com/activities/hello-world/#commit
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You should now be in the readme-edits branch.
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Click on README.md in the list and then click the pencil to edit the file
- now type in the editor
- when done click green button at bottom 'commit changes'
- commits can/should(?) be done early and often
- no change is too small to commit, but you'll get a feel for how often you should commit after some time
- but always write a commit message that describes your changes
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Now the master and readme-edits branches differ
https://guides.github.com/activities/hello-world/#pr
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Indirect Collaboration - pull requests
- Click the "Pull Request" tab, then "New pull request"
- In the Example Comparisons box, select the branch you made, readme-edits, to compare with master (the original).
- Proofread your changes in the diffs on the Compare page
- When ready to submit, click the Create Pull Request Button
- Write a title and a brief description of your changes
- Click Create Pull Request
https://guides.github.com/activities/hello-world/#merge
- Now, let's merge the Pull Request, to bring the changes from readme-edits into the master branch.
- Click the green Merge pull request button to merge the changes into master.
- Click Confirm merge.
- Now we can delete the readme-edits branch, since its changes have been incorporated into master. You'll be prompted to do so inside the purple box.
https://help.github.com/en/articles/resolving-a-merge-conflict-on-github
- Any time a merge is attempted when changes have been made to both versions of the same line of a file (in the master and in a fork, say), then you will have to resolve the conflicts in the merge.
- Often, you can just use the github interface to do this. If this is the case (i.e., the conflict isn't too complex), a Resolve Conflicts button will appear (and not be greyed-out).
- Clicking on "Resolve Conflicts" will show you the conflict and use symbols to indicate the location of the conflict (
<<<<<<<branch1-name
,=======
,>>>>>>>branch2-name
), and the two versions of the conflicting line. - Choose the correct version of the line (or edit one version), then remove the other version and remove the symbols and the branch/fork names, leaving only the text you want in the final version.
- Resolve any other marked conflicts in the file.
- Click on Mark as Resolved.
- Resolve conflicts in any other files.
- Click on Commit Merge (and click on the I understand pop-up).
- Finally, click on Merge Pull Request, and then confirm the merge.
https://guides.github.com/introduction/flow/
If you are not a collaborator in a repo, you can't branch that repo. However, you can "fork" it, which is just creates a clone of the repo on the GitHub server.
- You can't push changes directly back to the original repo.
- You'll want to work on keeping your fork in sync with the project
- add it to the original project as a remote, or
- fetching regularly from the original repo
Try forking from my repo, and make changes to the resulting fork, and then submit a pull request to me!
- Command Line Interface (CLI) cheat sheet
- Create your own Webpage (such as https://rjp0i.github.io/intro.html)
- Please, feel free to email me: ricky@virginia.edu
- The book Computing Skills for Biologists: A Toolbox contains a very useful introduction to Git, with practice data and code. Members of the UVA community can access the book online
- The examples, data, code and solutions are hosted on a github repo
- Lots of git/GitHub/GitLab resources from the source, as well as free training through a number of github sites
- StackOverflow is another good resource (e.g., for questions concerning git (or GitHub/GitLab): https://stackoverflow.com/questions/tagged/git
- use the following style of URL with two commit hashes (Rev A and Rev B)
- of the form: github.com/$USER/$REPO/compare/$REV_A...$REV_B
- $REV_A and B are the commit hashes for the versions you want to compare. You can get these by examining the Commit history of a file on Github
- Write some code, or some text
- Do the version control in github
- Edit it yourself
- Have a friend do some edits as well
# This is an additional edit for practice. Hopefully this works