A routine I used for monitoring campsite availability in Elkmont Campground, TN. An email (using Gmail API) will be sent to user once campsites are available.

Hard-coded parameters buried in the code file -- use caution when making changes, including but not limited to, campsite id (the url), start date, from/to in email settings, and all paths.

Python version is 3.6. A few more libraries are needed: selenium, BeautifulSoup, pandas, numpy.

Since using Gmail API, the Google authentication related libraries are needed, refere this link for details and get-started guide. The credentials.json has to exist as well.

Since using Selenium to inspect dynamic pages, a webdriver is needed. Refers to known issues for webdriver selection.

• The Firfox webdriver geckodriver is used in the main routine. safaridriver that came with the MacOS works fine when testing but produces error when running as cron job (for me). chromedriver seems to fail when doing the page navigating.

In terminal, type

$ env EDITOR=nano crontab -e

Add a line as:

*/2 * * * * /path_to_python/python /path_to_script/main.py

Then save the file.

*/2 means running the script every 2 minitues.

Use the line to check your cron jobs:

$ crobtab -l