dn42-lg

• A Python Flask Web Application Looking Glass for VyOS.
• Uses a mix of VyOS's GraphQL API and SSH to get data (through my network-automation library).
• Live at https://lg.usman.network

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Usage/Developer Notes

Create Virtual Environment, clone repo, and install dependencies.

conda create -n dn42-lg
conda activate dn42-lg
git clone https://github.com/usman-u/dn42-lg.git
poetry install

• The same should work with virtualenv and pip.

VSCode Remote

• If using VSCode SSH remote, change interpreter to conda env python path.

e.g. /home/usman/miniconda3/envs/dn42-lg/bin/python3

Confirm with which python3

(dn42-lg) usman@dev-usman-lan:~/projects/dn42-lg$ which python3
/home/usman/miniconda3/envs/flask-bgp-lg/bin/python3

Device Inventory

• Modify inventory.py to include your devices.
• It's a dictionary of OOP instances from my network-automation library.
• Use os.getenv() to get environment variables.

from net_automation import net_automation
import os

routers = {
    # router name:    API/SSH  instance.
    "fr_lil1": net_automation.Vyos(
        device_type="vyos",
        host="fr-lil1.usman.dn42",
        username="username",
        password=os.getenv("fr_lil1_password"),
        use_keys=False,
        url="https://fr-lil1.usman.dn42/graphql",
        key=os.getenv("apikey"),
    ),
}

Environmental Variables

• A .env file should be created.
• The .env file should be added to .gitignore.
• The .env file must include the flask secret key.

apikey = xxxx
fr_lil1_password = xxx
us_ca1_password = xxx
flask_secret_key = xxx

Running the Flask Development Server

(dn42-lg) usman@dev-usman-lan:~/projects/dn42-lg$ python main.py 
 * Serving Flask app 'main'
 * Debug mode: on
WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.
 * Running on all addresses (0.0.0.0)
 * Running on http://127.0.0.1:5000
 * Running on http://10.0.10.5:5000
Press CTRL+C to quit

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Deploying the Flask Application

• Flask Apps can be deployed in a variety of ways.
• I deployed it using Gunicorn, Systemd, and Nginx.
• See Flask's Deployment Options and this great Digital Ocean Blog for more information.