Visual shapefile inspector for PTI deployers

Launches a standalone Shiny app that renders the supplied shapefile list on a leaflet map so the deployer can visually spot holes, wrong boundaries, or geometry artefacts before running the calculation pipeline. Internally calls [validate_geometries()] with `error_on_fail = FALSE` and surfaces the structured diagnostic summary alongside the map. The app is read-only – it never mutates the inputs.

Usage

app_validate_shp(shp, app_name = "Validate shapefiles")

Arguments

shp

Named list of `sf` tibbles, one slot per admin level (same structure as the bundled [ukr_shp]). Slot names follow the `admin<N>_HumanName` convention (e.g. `admin1_Oblast`). Each layer must carry an `admin<N>Pcod` and `admin<N>Name` column. The app also renders shapes that fail [validate_geometries()] so the deployer can see what is wrong instead of getting a console error.

app_name

Character. Title shown in the browser tab and the page header. Defaults to `"Validate shapefiles"`.

Value

A [shiny::shinyApp()] object. Called primarily for its side effect of starting an interactive Shiny app.

Details

Use this in tutorial Step 1 (`build-pti-1-shapefiles.qmd`) or any time you receive a new country's boundary data: a 30-second visual pass catches misaligned admin levels, dropped polygons, and projection mistakes that a structural validator alone misses.

See also

[validate_geometries()] for the underlying structural validator; [launch_pti()] for the full PTI app.

Other validation: app_validate_metadata(), drop_inval_adm(), mod_drop_inval_adm(), validate_geometries(), validate_metadata(), validate_read_metadata(), validate_read_shp()

Examples

if (FALSE) { # \dontrun{
# Inspect the bundled Rwanda shapefile.
app_validate_shp(rwa_shp)

# The app still renders if a layer is structurally broken -- useful
# for spotting *what* is wrong rather than only *that* something is.
broken <- rwa_shp
broken$admin1_Province$admin1Pcod <- NULL
app_validate_shp(broken)
} # }