This is a simple script for scraping availability of campgrounds! The recreation.gov api doesn't reveal campsite availability, so this script spoofs a session through their search portal to allow programmatic polling of campsite availability.

It's currently hardcoded for yosemite, but with a bit of network sniffing you can reconfigure for other national parks.

List of campsites with availabilities on queried dates + links.

UPPER PINES, Booking Url: http://www.recreation.gov/unifSearchInterface.do?interface=bookcamp&contractCode=NRSO&parkId=70925
LOWER PINES, Booking Url: http://www.recreation.gov/unifSearchInterface.do?interface=bookcamp&contractCode=NRSO&parkId=70928
NORTH PINES, Booking Url: http://www.recreation.gov/unifSearchInterface.do?interface=bookcamp&contractCode=NRSO&parkId=70927

Install requirements:

pip install -r requirements.txt

Use: python campsites.py --start_date 2015-04-24 --end_date 2015-04-25

Best use is to set a crontab on a ~5 minute interval (I've found that a 10-minute interval is too long because the campsites will be taken by the time I'm able to act on the alert).

campsites.sh demos a simple bash script wrapping the python script and opening a text file if results are found that could be set up to be triggered through cron.

• Use your preferred proxy or network analyzer to capture requests (Charles Proxy, Wireshark, etc)
• Visit recreation.gov in your browser
• Enter target park name - click the park in the prefilled Auto-suggest dropdown that appears
• Find logs for the POST request to www.recreation.gov/unifSearch.do
• Copy the REQUEST body params as JSON into the LOCATION_PAYLOAD dict in campsites.py
• (keep the search results page open and continue to next section)

• From the list of campgrounds and attractions listed in the results for your park, choose the campgrounds you'd like to stay at
• For each campground you choose, copy the campground's link URL
• Grab the parkId URL param and add it as a key to the PARKS dict in campsites.py, the value should be a human readable campground name.