Contact The CCI Helpdesk

Python Web Applications on Tux

Before following this documentation, you will either need to be on the campus network or connected to the Drexel VPN. If you are off campus, make sure you are connected to Drexel VPN following the instructions at VPN.


To run Python web applications on Tux, you should start by connecting to Tux following the instructions at Tux Account Information. 


Once connected to Tux, run the command:

ssh node

Note that you may need to accept the SSH host key, as you did with Tux, as well as enter your password a second time. This is expected and you can type "yes" at this prompt.

ssh_authenticity

This will connect you to CCI's web application server, node.cci.drexel.edu. This is where your web application will be served.


Next, you should create a virtual environment. This will keep the packages you need for your web application together and give you control over which versions of the apps you're running. The directory can be called anything that makes sense for your app, and can be stored anywhere in your home directory. Your virtual environment can also use any name you like, but should always live inside your web app's directory. For this example, we are calling the web app directory "python-web-app" and the virtual environment "venv".

# create a directory for your web app and cd to it
mkdir python-web-app  
cd python-web-app

# create a virtual environment 
virtualenv venv

# activate the virtual environment
source venv/bin/activate

Note that you'll have to activate the virtual environment to work on your project - if you log out, when you log back in to node.cci.drexel.edu, make sure to run the command "source venv/bin/activate" before running your code.


Python Web Apps with Flask

First, from your virtualenv, make sure to install the Flask module:

pip install flask

Then, create a file "test.py" and fill it with the following code, replacing "{{PORT_NUM}}" with the port number you've been assigned at {{NEW_PORT_ASSIGNMENT_PAGE}}

from flask import Flask

app = Flask(__name__)

@app.route("/")
def hello_world():
    return "<p>Hello, World!</p>"

if __name__ == '__main__':
    app.run(debug=True, port={{PORT_NUM}})

Save the file and run the command

pm2 start test.py --interpreter venv/bin/python3

This will submit the Python application to pm2, the process manager we use on the Node server to manage web applications. This allows you to disconnect from Node without your application going offline - useful for handing access over to a TA or faculty member for grading. More details on use of pm2 can be found at PM2 Command List.


As long as the command "pm2 status" shows that your application is online, you should be ready to visit your web application from your web browser. 

pm2 status

Navigate to https://node.cci.drexel.edu/?port={{PORT_NUM}} in order to access your website.

CCI Support Site