Technical Hints


You can clone the assignment repositories using either HTTPS and SSH, but we recommend using SSH because you do not need to enter your credentials everytime you pull and push once you set it up for the first time.

There seems to be an access issue (code: 403) with HTTPS cloning. In that case, please try the SSH way.

How to set up Git SSH authentication

Please check whether you have a SSH key generated already: there should be id_rsa and in ~/.ssh. If yes, please go to step 3.

  1. Generate a SSH key on your local machine. Run the following command in a terminal. Follow the prompts to store the key in ~/.ssh and enter a passphrase (it can be empty, or a phrase you like).

    ssh-keygen -t rsa -C ""
  2. Navigate to ~/.ssh. Note that this is a hidden folder by default. You should see id_rsa (private key) and (public key).

  3. Open the with a text editor or using the command cat (on *nix OS), and copy the entire content, which should be a long string.

  4. Open the settings in your students github account, navigate to the SSH and GPG key tab (on the left sidebar), and then upload your public key.

  5. You should be able to use the SSH link to clone repositories.

Note: do not upload or send out your private key. It is supposed to be on your own machine.

Static server

When developing a visualization, the data files are usually loaded dynamically using Javascript, such as d3.csv(). In this case, you will need to start a static file server to serve all your HTML/CS/JS and data files. We recommend two simple options to start a server, then you can view the results on a browser using http://localhost:[PORT-NUMBER].

Note that you should start the server in the project directory.

Debugging JavaScript & D3

The developer tools in Chrome, Firefox, and Microsoft Edge (Chromium) have very similar capabilities:

Try using the debugger built into your browser to do each of these operations:

Or you can use, for example, Jetbrains WebStorm for programming and debugging JavaScript if you prefer an IDE. It's free for students.