We will start by introducing you to Git, GitHub, and the collaboration features we will use throughout the class. Even if you have used GitHub in the past, we hope this information will provide a baseline understanding of how to use it to build better software!
GitHub is a collaboration platform built on top of a distributed version control system called Git.
In addition to being a place to host and share your Git projects, GitHub provides a number of features to help you and your team collaborate more effectively. These features include:
- Pull Requests
- Organizations and Teams
Rather than force you into a "one size fits all" ecosystem, GitHub strives to be the place that brings all of your favorite tools together. For more information on integrations, check out https://github.com/integrations.
You may even find some new, indispensable tools to help with continuous integration, dependency management, code quality and much more.
- a distributed version control system or DVCS.
- free and open source.
- designed to handle everything from small to very large projects with speed and efficiency.
- easy to learn and has a tiny footprint with lightning fast performance.
Git features cheap local branching, convenient staging areas, and multiple workflows.
As we begin to discuss Git (and what makes it special) it would be helpful if you could forget everything you know about other version control systems (VCSs) for just a moment. Git stores and thinks about information very differently than other VCSs.
We will learn more about how Git stores your code as we go through this class, but the first thing you will need to understand is how Git works with your content.
One of the first ideas you will need understand is that Git does not store your information as series of changes. Instead Git takes a snapshot of your repository at a given point in time. This snapshot is called a commit.
Git is optimized for local operation. When you clone a copy of a repository to your local machine, you receive a copy of the entire repository and its history. This means you can work on the plane, on the train, or anywhere else your adventures find you!
Branches are an essential concept in Git.
When you create a new branch in Git, you are actually just creating a pointer that corresponds to the most recent snapshot in a line of work. Git keeps the snapshots for each branch separate until you explicitly tell it to merge those snapshots into the main line of work.
Which brings us to our final point for now; Git is very explicit. It does not do anything until you tell it to. No auto-saves or auto-syncing with the remote, Git waits for you to tell it when to take a snapshot and when to send that snapshot to the remote.
A repository is the most basic element of GitHub. It is easiest to imagine as a project's folder. However, unlike an ordinary folder on your laptop, a GitHub repository offers simple yet powerful tools for collaborating with others.
A repository contains all of the project files (including documentation), and stores each file's revision history. Whether you are just curious or you are a major contributor, knowing your way around a repository is essential!
There are two account types in GitHub, user accounts and organization accounts. While there are many differences in these account types, on of the more notable differences is how you handle permissions.
When you signed up for GitHub, you were automatically given a user account. Permissions for a user account are simple, you add people as collaborators to specific repositories to give them full read-write access to the project.
Organization accounts provide more granular control over repository permissions. In an organization account you create teams of people and then give those teams access to specific repositories. Permissions can be assigned at the team level (e.g, read, write, or admin).
The code view is where you will find the files included in the repository. These files may contain the project code, documentation, and other important files. We also call this view the root of the project. Any changes to these files will be tracked via Git version control.
Issues are used to track bugs and feature requests. Issues can be assigned to specific team members and are designed to encourage discussion and collaboration.
A Pull Request represents a change, such as adding, modifying, or deleting files, which the author would like to make to the repository. Pull Requests help you write better software by facilitating code review and showing the status of any automated tests.
Projects allow you to visualize your work with Kanban style boards. Projects can be created at the repository or organization level.
Wikis in GitHub can be used to communicate project details, display user documentation, or almost anything your heart desires. And of course, GitHub helps you keep track of the edits to your Wiki!
Pulse is your project's dash board. It contains information on the work that has been completed and the work in progress.
Graphs provide a more granular view into the repository activity, including who has contributed, when the work is being done, and who has forked the repository.
The README.md is a special file that we recommend all repositories contain. GitHub looks for this file and helpfully displays it below the repository. The README should explain the project and point readers to helpful information within the project.
The CONTRIBUTING.md is another special file that is used to describe the process for collaborating on the repository. The link to the CONTRIBUTING.md file is shown when a user attempts to create a new issue or pull request.
The ISSUE_TEMPLATE.md (and its twin the pull request template) are used to generate templated starter text for your project issues. Any time someone opens an issue, the content in the template will be pre-populated in the issue body.
In GitHub, you will use issues to record and discuss ideas, enhancements, tasks, and bugs. Issues make collaboration easier by:
- Replacing email for project discussions, ensuring everyone on the team has the complete story, both now and in the future.
- Allowing you to cross-link to related issues and pull requests.
- Creating a single, comprehensive record of how and why you made certain decisions.
- Allowing you to easily pull the right people into a conversation with @ mentions and team mentions.
Follow these steps to create an issue in the class repository:
- Click the Issues tab.
- Click New Issue.
- Type the following in the Subject line:
- In the body of the issue, include the text below:
YOUR-USERNAME will choose an image, add a caption, and add both to a file. - [ ] Create a branch - [ ] Edit the file - [ ] Commit the changes - [ ] Create a Pull Request - [ ] Request a Review - [ ] Make more changes - [ ] Get an approval - [ ] Merge the Pull Request
GitHub uses a syntax called Markdown to help you add basic text formatting to Issues, Pull Requests, and files with the
# indicates a Header. # = Header 1, ## = Header 2, etc.
- followed by a space will create a bulleted list.
** on either side of a string will make that text bold.
- followed by a space and
[ ] will create a handy checklist in your issue or pull request.
When you @mention someone in an issue, they will receive a notification - even if they are not currently subscribed to the issue or watching the repository.
# followed by the number of an issue or pull request (without a space) in the same repository will create a cross-link.
Tone is easily lost in written communication. To help, GitHub allows you to drop emoji into your comments. Simply surround the emoji id with
GitHub Pages enable you to host free, static web pages directly from your GitHub repositories. Several of the projects we use in class will use GitHub Pages as the deployment strategy. We will barely scratch the surface in this class, but there are a few things you need to know:
- You can create two types of websites, a user/organization site or a project site. We will be working with project websites.
- For a project site, GitHub will only serve the content on a specific branch. Depending on the settings for your repository, GitHub can serve your site from a
gh-pagesbranch, or a
/docsfolder on the
- The rendered sites for our projects will appear at