Why not use the GitHub web interface?
We could easily setup our new repository using GitHub’s nice web interface, but the point of this blog is writing code and gaining experience with all the tools at our disposal. Also we can create a quick bash script that automatically setups up a new repo and clones it into our current directory which should help make the process more seamless.
Installing curl
curl is command line tool for making http request (and many other protocols) which we will be using to make RESTful http calls to access GitHub’s API.
In your terminal run
sudo apt-get curl
Creating a GitHub Repository
Following the current GitHub API for creating a new repo at http://developer.github.com/v3/repos/#create we can produce a single command that will create our new repo and set some basic configuration options.
curl -u USERNAME https://api.github.com/user/repos -d "{\"name\":\"REPONAME\",\"description\":\"REPODESCRIPTION\",\"gitignore_template\":\"LANG\", \"auto_init\":true}"
Enter your GitHub password and curl will print the json message if the request was succesful.
The flags for used here for curl are pretty simple. -u specifies the username for authentication and -d takes the data, json in this case, to send to the server. In this example -d also defaults the request method to POST. If you need to use a different request method you can use the -X flag to specific (ie -X DELETE).
Cloning the Respository
We need to get the newly created repository copied down to our local machine. Git provides us with the clone command to pull remote repositories into a local directory.
git clone githubrepourl
Just run the above command replacing the githubrepourl with the url of your repository and it will be copied down into a new directory named the same as your repo. You can again use the GitHub API to view a list of all your repositories and get the clone url. Run
curl -u username https://api.github.com/user/repos
and look at the clone_url field for the repository you want to clone.
Bringing it together with bash script
Finally we can combine the above into a single simple to use script.
#!/bin/bash
DESCRIPTION=
NAME=
LANG=
USER=
howto()
{
cat << EOF
$0 usage
This script creates and initializes a remote github repo and clones it into the CURRENTDIR/NAME
-n name of repo and folder to create in current directory
-d repo description
-u github username
-l programming language for .gitignore
EOF
}
while getopts "n:d:l:u:" OPTION
do
case $OPTION in
d) DESCRIPTION=$OPTARG ;;
l) LANG=$OPTARG ;;
u) USER=$OPTARG ;;
n) NAME=$OPTARG ;;
?) howto; exit ;;
esac
done
if [[ -z $DESCRIPTION ]] || [[ -z $LANG ]] || [[ -z $USER ]] || [[ -z $NAME ]]
then
howto
exit
fi
curl -u $USER https://api.github.com/user/repos -d "{\"name\":\"$NAME\", \"description\":\"$DESCRIPTION\",\"gitignore_template\":\"$LANG\", \"auto_init\":true}"
git clone https://github.com/$USER/$NAME.git
I am new to bash scripting, so lets take a look at a few important lines in the following script to understand what they do.
All linux scripts, including others than bash, require the first line the script to be a #! followed by the path to the binary the will accept the script as input and execute it. The path to bash is /bin/bash.
Similar to C, we can define functions in bash scripts. Their syntax goes functionname (params) { code }. Unlike C, we don’t need to specify any return or parameter types.
To parse command line parameters bash provides us with getopts which takes string where a single character maps to the a flag on the command line (‘n’ maps to -n) and if followed by an optional : then we are provided the string passed directly after the flag. We then store each of the defined flag into a variable for later use and verify that they had values passed in by using the if statement and test [[ ]] with the -z flag.
Finally we take the curl and git clone commands we created and do some simple replacements with our variables.
Let’s copy our new script into /usr/local/bin/ and we can use it from the command line to create a new repository any time we need.
You can access the preceding code and any other bash scripts I write in the future at https://github.com/sgarlick987/bash-scripts/ which I created using the above script.
Naming Stuff is Hard 