Every Layer a Project Holds, Under Either Layout

Use this in place of sf::st_layers(<one file>)$name, which cannot see a split project at all. Reads each GeoPackage's registered tables rather than trusting file names, so a file holding an unexpected table is still reported honestly.

Usage

rfp_layout_layers(spec)

Arguments

spec

A layout spec from rfp_layout(). Not a path - a bare path would have to mean the project directory here, while everywhere else in rfp a bare GeoPackage path means the monolith layout at that file. Resolve it first.

Value

A data frame with layer and file, ordered by layer. Zero rows when nothing exists.

Details

unique(x$file) is every rfp-managed GeoPackage in the project - what a whole-file operation wants, whether that is a backup list, ogr2ogr or VACUUM. One divergence to know about: a GeoPackage carrying no registered table has no row here, so it is not listed.

Zero rows is the honest answer for a project with no layers yet. A caller that requires some should say so itself with nrow(), rather than this raising on its behalf.

See also

Other manifest: rfp-layout, rfp_layout(), rfp_layout_layer_path(), rfp_manifest_create(), rfp_manifest_read(), rfp_manifest_types(), rfp_project_audit(), rfp_project_slim(), rfp_project_split(), rfp_project_update()

Examples

project <- file.path(tempdir(), "layout_layers_example")
dir.create(project)
file.copy(
  system.file("testdata", "subset_fixture", "parent",
              "background_layers.gpkg", package = "rfp"),
  project
)
#> [1] TRUE

layers <- rfp_layout_layers(rfp_layout(project))
layers$layer
#> [1] "lakes"           "roads"           "streams"         "unused_sentinel"
unique(layers$file)
#> [1] "/tmp/RtmpfSNDuG/layout_layers_example/background_layers.gpkg"

unlink(project, recursive = TRUE)