road-trip-planner

A primitive road trip planner between U.S. National Parks. This project uses Datalog to discover feasible road trip plans against data from the National Park Service. The core logic is in the souffle directory, with a small utility CLI runner on top.

This was my final project for a course in Database Management Systems. I wrote about the exploration here, if you are interested.

reqs

1. souffle
2. cargo

Note: To run the planner with the --lucky option to output a single plan, you'll need to build souffle from source from a recent commit, as the choice construct has not yet been released.

install

Basically just clone the repo. This tool can be used via cargo run, or you can install it to your PATH e.g.

# get repo and install binary
git clone git@github.com:samtay/road-trip-planner.git
cd road-trip-planner
cargo install --path .

but either way, this tool expects to be run from the root of this repository, so it can easily access the data, souffle, and output directories.

Currently this planner looks for campgrounds that allow a 34' RV. You can adjust that variable here.

usage

The help output explains the usage:

USAGE:
    road-trip-planner [FLAGS] <from> <to>

ARGS:
    <from>    Starting park code (e.g. ever)
    <to>      Ending park code (e.g. olym)

FLAGS:
    -h, --help       Prints help information
    -l, --lucky      Output a single trip
        --min        Use minimum distance between stops (for --lucky)
    -r, --refresh    Use fresh NPS data
    -V, --version    Prints version information

But this requires a few explanations: the park codes can be found in the park.facts file. Also, enumeration may take a very long time if the parks are far apart; if this happens, try adjusting the required progress between segments here. The --lucky option uses souffle's choice construct to make a single plan; however, it doesn't do this in any intelligent way, so it is possible for the plan to fail and stop short before the final destination.

Using --refresh will fetch the latest data from NPS, however this does require a valid NPS_API_KEY environment variable. This key can be obtained for free from NPS here.

examples

# non-deterministically find a single plan from badlands to glacier national park
❯ road-trip-planner --lucky badl glac
       Badlands National Park: Cedar Pass Campground         (0.00)
                             ↡
Bighorn Canyon National Recreation Area: Afterbay Campground (314.16)
                             ↡
                Glacier National Park: Apgar                 (675.59)

# enumerate all plans from yosemite to the olympic national forest
❯ road-trip-planner yose olym
Plan 1
------
    Yosemite National Park: Crane Flat Campground     (0.00)
                          ↡
Whiskeytown National Recreation Area: Brandy Creek RV (247.61)
                          ↡
Olympic National Park: Heart O' the Hills Campground  (761.96)
.
.
.
Plan 4316
---------
            Yosemite National Park: Wawona Campground              (0.00)
                                ↡
     Lassen Volcanic National Park: Warner Valley Campground       (220.53)
                                ↡
Lake Roosevelt National Recreation Area: Spring Canyon Group Sites (752.22)
                                ↡
              Olympic National Park: Mora Campground               (1014.45)

todo

1. Include the cell, internet, and dump amenities in the enumeration output. These can then be externally counted, so that plans can be sorted by stops with the most cell service, or to filter plans that include at least one dump stop every 500mi, etc..
2. A few more things should be parameterized from the CLI, such as the RV length, minimum progress and maximum segment distance. The minimum progress turns out to be a very important parameter, and makes the difference of whether or not the computation finishes in a second or days.
3. Call out to an API for actual driving distance and/or time, instead of using the haversine approximation.
4. Indicate an error when the choice domain fails to reach the final destination.