CSCI 102T

The Socio-Techno Web

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Lab 1: Intro to Git and Workflow

In this lab, we will explore tools, techniques, and workflows used by many programmers. We will adopt some of these best practices and use them for managing our written and lab assignments, collaborating, and exchanging feedback.

The skills developed in this lab will help us on multiple fronts. The tools that we explore (Terminal.app, the Atom text editor) and the workflow we use (checkpointing our progress using the Git version control system) will help us to work efficiently, safely, and collaboratively throughout the semester. In the next lab, we will begin creating a webpage that will ultimately be the home for all of our lab and written assignments.

We will continue to use these tools and this workflow for the rest of the semester.

Step 0: Lab Preparation

Please complete Step 0 before entering lab.

• Read these two short descriptions of what a version control system is and why you might want to use one. We will talk about these more in lab.
• Sign up for a GitHub account. Please thoughtfully choose a username so that I can reasonably infer who you are from it. Make sure to choose the free plan (it's the default) and don't set up an organization. You can skip the little quiz they give you by clicking the skip this step link at the bottom of the page. However, please complete the "Hello World" guide. (If you accidentally exit the guide, you can navigate back to the Hello World guide here.) We will be using those features throughout the semester.
• After you've registered, please send me an email with your GitHub username. I will add you to the GitHub Williams CS organization.

Step 1: Forking

Navigate to the CS102 GitHub starter repository. Fork the repository by using the Fork button in the top right-hand corner. This copies the repository to your GitHub account.

Now that you have created your own private version of the repository (it is not part of the Williams CS GitHub organization), let's change your repository's name.

• Click on the Settings button, update the Repository name field, and click Rename.
• Change the repository name to be cs102-lab1.

Step 2: Cloning

You should now have a copy of the repository in your own GitHub account. Clone the repository to your local disk using the following steps.

• Click the green "clone or download" button on the right side of the repository page, above the list of repository contents. You can clone via HTTPS or SSH. We'll use HTTPS, so first click on the "Use HTTPS" link and then click on the little clipboard with an arrow icon to copy the URL to the local clipboard.
• Open up the Terminal.app application and navigate to your home directory by typing

  $ cd

• Make a new directory called cs102 using

  $ mkdir cs102

  If you open up Finder, you should see a new folder called cs102 appear in your home directory!


• Change directories into cs102 using

  $ cd cs102

• Now clone your fork of cs102-starter by typing "git clone" and then pasting the copied repo on the command line (⌘-v). It should look like this:

  $ git clone https://github.com/<git-username>/cs102-lab1.git

  (It will prompt you for your username, and then for your password)


• Change directories into the new repository directory using

  $ cd cs102-lab1

Step 3: Text Editors

There are many good text editors. People swear by emacs and vim. In a pinch, you can also use nano. Currently, many people like sublime. The last time this course was taught, everyone used TextWranger. Despite all of those wonderful options, today we will use Atom (but in the future feel free to use whatever you want).

• Open the README.md file in Atom:
  • Using the launcher, search for and open the Atom application.
  • Go to the File menu, click on Open, and select the cs102-lab1 folder that you just created.
  • In the left pane, you will see a list of all of the files in your project. Click on the README.md file.
• Edit README.md with a description for your repository. You may be surprised by the way README.md looks in Atom compared to how it looked on GitHub. This is because GitHub understands and formats "Markdown", just like a Web Browser understands and formats HTML. You may want to use the github markdown syntax to format your file so that it displays nicely on github.com.
• When you are done making changes, save your file. (If a file's tab has a little blue dot, that means it has unsaved changes!)

Step 4: Submitting Code

We will use Git and GitHub for submitting lab assignments. We will also GitHub to share our websites with our tutorial partners.

• Commit your changes

  Recall that you cloned a forked repository to your local disk. You need to save your changes to your locally cloned repository by committing them using

  $ git commit -m "Updated my repository's Readme"
  	  README.md

  What this command does is tell the git program that you want to commit the current state of some files in your repository. The -m option tells git that you want to add a message to your project's history to help you to log notes about the changes you made. You put the message inside of quotes. Only the files that are listed after the message will be committed.
  
  If this is the first time you have ever used git on this computer, you will be prompted with a message in the Terminal. These are instructions to configure git on your account to set some defaults. If you have any questions about the meanings of those messages, ask an instructor or TA.

• Push your changes to GitHub

  You will now push these changes back to your forked repository on GitHub using

  $ git push

• Verify your changes on Github

  Navigate now in your web browser to your forked repository on GitHub. It should be available at

  https://github.com/<git-username>/cs102-lab1

  You should see your changes reflected in the README.md file displayed there.

• Issue a pull request

  You should see a little green button next to the repository name and branch on your GitHub repository page. Clicking this link will issue a pull request to the base repository from which the fork was originally made. Go ahead and issue a pull request.