fetch_app_upload: Launch Interactive Fetch App with File Upload

In lakefetch: Calculate Fetch and Wave Exposure for Lake Sampling Points

Launch Interactive Fetch App with File Upload

Description

Launch a standalone Shiny app where users can upload a CSV file with GPS coordinates, and the app will automatically download lake boundaries, calculate fetch, and display interactive results.

Usage

fetch_app_upload(title = "Lake Fetch Calculator")

Arguments

title

Optional app title (default: "Lake Fetch Calculator")

Details

Requires the shiny, leaflet, and base64enc packages (suggested dependencies).

The app workflow:

1. Upload a CSV file with latitude/longitude columns

2. App downloads lake boundaries from OpenStreetMap

3. Calculates fetch for all uploaded points

4. Displays interactive map with results

5. Click anywhere on a lake to analyze additional points

6. Download results as CSV or GeoPackage

CSV file requirements:

• Must have columns starting with "lat" and "lon" (case-insensitive)

• Optional "Site" column for point names

• Additional columns are preserved in output

Value

Launches a Shiny app (does not return)

Examples

if (interactive()) {
  # Launch the upload app
  fetch_app_upload()
}

lakefetch documentation built on March 20, 2026, 5:10 p.m.