Git & Github

 

Dhrumil Mehta

 

Database Journalist, Politics - FiveThirtyEight

Democracy and Technology Fellow - Harvard Kennedy School

 

dhrumil.mehta@fivethirtyeight.com  

 @datadhrumil

@dmil

To Do

 

​

 

Command Line

whoami # your username
hostname # my computer's network name
echo "Hello, World!" # print text to terminal

pwd # print working directory
cd # change directory
ls # list directory

cat <filepath> # print a whole file

Commands

whoami # your username
hostname # my computer's network name
echo "Hello, World!" # print text to terminal

pwd # print working directory
cd # change directory
ls # list directory

cat <filepath> # print a whole file

mkdir <directory_path> # make directory
rmdir <directory_path> # remove directory
cp <from> <to> # copy a file or directory
mv <from> <to> # move a file or directory

More Commands

# Command
ls

# Command with flag
ls --all

# Shorthand flag
ls -a

ls -l

ls -la

# Command with argument
ls folder/

# Command with flags and argument
ls -la folder/

# Manual, to learn all the different flags and arguments
man ls

# or

ls --help

Parts of a Command

  • Take some time to cd around and explore your filesystem. See what is at the root, see if you can find some of the files you use daily.

Try It:

  • Navigate to your desktop in the terminal
  • Create a folder on the desktop using mkdir, call it something like "dhrumil-simple-website"
  • cd into your new folder

Try It:

Piping

echo "Hello, World." > hello.txt
# ">" Grabs the output from the command on the 
# left and feeds it to the file on the right

echo "Goodbye, World." >> hello.txt
# ">>" is similar to ">" except if the file already 
# exits it will append to the end of it rather than
# overwriting the file

grep 'ood' hello.txt
# grep is a command that searches a file for a
# regular expression, we can try it on hello.txt

ls -a1 | grep .txt
# "|" takes the output of the command to the left and
# uses it as the input for the command to the right

Additional Resources

 

HTML

Simple HTML Page

<!DOCTYPE html>
<html>
<body>

<h1>My First Heading</h1>

<p>My first paragraph.</p>

</body>
</html>

Make a folder on the Desktop with a file called index.html

index.html

mkdir ~/Desktop/dhrumil-website
cd ~/Desktop/dhrumil-website
touch index.html

Additional Resources

 

Git & Github

  • Git: A distributed version control system
  • GitHub: a hosting service for Git repositories.

Git

Create a git repository

# Initialize the local directory as a Git repository.
git init

# View which files are in the staging area
git status

# Add the files to your new repository's staging area.
git add index.html

# View which files are in the staging area
git status

# Commit the files that you've staged in your local repository
# with a descriptive commit message.
git commit -m "add index page"

git add index.html

working directory

staging area 

repository

git commit -m "add index page"

Local

index.html

.git

Try It:

  • Make the following changes:
    • Change the title to your name
    • Add a description of the page
    • Add a link to your github account
  • Commit after EACH change

 

Example:

<!DOCTYPE html>
<html>
<body>

<h1>Dhrumil Mehta</h1>

<p>This is my simple website.</p>
<a href="http://www.github.com/dmil">Find me on Github!</a>

</body>
</html>
  • Show the commit history with your 3 new commits

 

git log

Github

Create an empty github repository: https://github.com/new

 

Pushing to Github

https://help.github.com/articles/adding-an-existing-project-to-github-using-the-command-line/

# Sets the new remote
git remote add origin <remote repository URL>

# Verifies the new remote URL
git remote -v

# Push the changes in your local repository to GitHub.
git push origin master

git push

Remote

 

git add index.html

working directory

staging area 

repository

git commit -m "add index page"

Local

index.html

.git

Collaboration

Add Collaborator

cd ~/Desktop
git clone <remote_url>

Clone your Neighbor's Repo

Branching

# See your branches
git branch

# Checkout a new branch
git checkout -b <branch_name>

# push the branch to github
git push origin <branch_name>

# Checkout an existing branch
git checkout <branch_name>

Issue a Pull Request

Try It:

Create a branch called "endorsement"

 

Write something nice about your neighbor

 

Commit the change and issue a "pull request"

Open Source Collaboration

Forking

Forking and Pull Requests

(Open Source Collaboration Model)

http://stackoverflow.com/questions/3611256/forking-vs-branching-in-github

Forking and Pull Requests

(Open Source Collaboration Model)

# 1) Fork this repo in github
#    https://github.com/dmil/learning-github

# 2) Make a local clone of your fork
git clone <url_of_your_fork>

# 3) Add yourself to the attendance list
echo "Dhrumil Mehta" >> README.md

# 4) Commit your changes
git add README.md
git commit -m "add dhrumil to attendance"

# 5) Push the file to your own github
git push origin master

# 6) Issue a pull request to me on github

# 7) Wait for everyone to finish and for me to merge 
#    the pull requests into the upstream branch.

# 8) Pull the changes from upstream to get the full attendance list 
git remote add upstream https://github.com/dmil/tools-of-the-trade.git
git pull upstream

# 9) Push back to your repo
git push origin master

Other Github Features

Additional Resources

 

dhrumil.mehta@fivethirtyeight.com  

 @datadhrumil

@dmil 

 

http://fivethirtyeight.com/contributors/dhrumil-mehta/​