Add format creation method, and update tar_terra_rast()

.Rbuildignore

@@ -4,3 +4,10 @@
 ^\.github$
 ^codecov\.yml$
 ^LICENSE\.md$
+
+^_targets$
+^_targets_r$
+^_targets\.R$
+^_targets_packages\.R$
+^_targets\.Rmd$
+^_targets\.yaml$

.gitignore

@@ -4,3 +4,11 @@
 .httr-oauth
 .DS_Store
 .quarto
+.Rprofile
+
+_targets_packages.R
+_targets
+_targets.R
+_targets.Rmd
+_targets_r
+_targets.yaml

DESCRIPTION

@@ -14,6 +14,12 @@ Authors@R: c(
  family = "Scott",
  role = c("aut"),
  comment = c(ORCID = "0000-0002-7430-7879")
+ ),
+ person(
+ given = "Andrew",
+ family = "Brown",
+ role = c("aut"),
+ comment = c(ORCID = "0000-0002-4565-533X")
  )
  )
 Description: Provides extensions for various geospatial file formats, 
@@ -30,6 +36,8 @@ Imports:
  terra
 Suggests: 
  testthat (>= 3.0.0)
+Depends:
+ R (>= 4.1.0)
 Config/testthat/edition: 3
 URL: https://github.com/njtierney/geotargets
 BugReports: https://github.com/njtierney/geotargets/issues

NAMESPACE

@@ -1,3 +1,5 @@
 # Generated by roxygen2: do not edit by hand
 
+export(tar_terra_rast)
+export(tar_terra_vect)
 importFrom(utils,globalVariables)

R/tar-terra-rast.R

@@ -0,0 +1,135 @@
+#' Create a terra _SpatRaster_ Target
+#'
+#' Creates a target for a terra _SpatRaster_ object.
+#'
+#' @param filetype character. File format expressed as GDAL driver names passed to `terra::writeRaster()`
+#' @param gdal character. GDAL driver specific datasource creation options passed to `terra::writeRaster()`
+#' @param ... Additional arguments not yet used
+#'
+#' @inheritParams targets::tar_target
+#'
+#' @seealso [targets::tar_target_raw()]
+#' @export
+#' @examples
+#' if (Sys.getenv("TAR_LONG_EXAMPLES") == "true") {
+#' targets::tar_dir({ # tar_dir() runs code from a temporary directory.
+#' library(geotargets)
+#' targets::tar_script({
+#' list(
+#' geotargets::tar_terra_rast(
+#' terra_rast_example,
+#' system.file("ex/elev.tif", package = "terra") |> terra::rast()
+#' )
+#' )
+#' })
+#' targets::tar_make()
+#' x <- targets::tar_read(terra_rast_example)
+#' })
+#'}
+tar_terra_rast <- function(name,
+ command,
+ pattern = NULL,
+ filetype = NULL,
+ gdal = NULL,
+ ...,
+ tidy_eval = targets::tar_option_get("tidy_eval"),
+ packages = targets::tar_option_get("packages"),
+ library = targets::tar_option_get("library"),
+ repository = targets::tar_option_get("repository"),
+ iteration = targets::tar_option_get("iteration"),
+ error = targets::tar_option_get("error"),
+ memory = targets::tar_option_get("memory"),
+ garbage_collection = targets::tar_option_get("garbage_collection"),
+ deployment = targets::tar_option_get("deployment"),
+ priority = targets::tar_option_get("priority"),
+ resources = targets::tar_option_get("resources"),
+ storage = targets::tar_option_get("storage"),
+ retrieval = targets::tar_option_get("retrieval"),
+ cue = targets::tar_option_get("cue")) {
+
+ name <- targets::tar_deparse_language(substitute(name))
+
+ envir <- targets::tar_option_get("envir")
+
+ command <- targets::tar_tidy_eval(
+ expr = as.expression(substitute(command)),
+ envir = envir,
+ tidy_eval = tidy_eval
+ )
+
+ pattern <- targets::tar_tidy_eval(
+ expr = as.expression(substitute(pattern)),
+ envir = envir,
+ tidy_eval = tidy_eval
+ )
+
+ # could pull defaults from geotargets package options
+ if (is.null(filetype)) {
+ filetype <- "GTiff"
+ }
+
+ if (is.null(gdal)) {
+ gdal <- "ENCODING=UTF-8"
+ }
+
+ targets::tar_target_raw(
+ name = name,
+ command = command,
+ pattern = pattern,
+ packages = packages,
+ library = library,
+ format = create_format_terra_raster(filetype = filetype, gdal = gdal, ...),
+ repository = repository,
+ iteration = iteration,
+ error = error,
+ memory = memory,
+ garbage_collection = garbage_collection,
+ deployment = deployment,
+ priority = priority,
+ resources = resources,
+ storage = storage,
+ retrieval = retrieval,
+ cue = cue
+ )
+}
+
+#' @param filetype File format expressed as GDAL driver names passed to `terra::writeRaster()`
+#' @param gdal GDAL driver specific datasource creation options passed to `terra::writeRaster()`
+#' @param ... Additional arguments not yet used
+#' @noRd
+create_format_terra_raster <- function(filetype, gdal, ...) {
+
+ if (!requireNamespace("terra")) {
+ stop("package 'terra' is required", call. = FALSE)
+ }
+
+ # get list of drivers available for writing depending on what the user's GDAL supports
+ drv <- terra::gdal(drivers = TRUE)
+ drv <- drv[drv$type == "raster" & grepl("write", drv$can), ]
+
+ if (is.null(filetype)) {
+ filetype <- "GTiff"
+ }
+
+ filetype <- match.arg(filetype, drv$name)
+
+ .write_terra_raster <- function(object, path) {
+ terra::writeRaster(
+ object,
+ path,
+ filetype = NULL,
+ overwrite = TRUE,
+ gdal = NULL
+ )
+ }
+ body(.write_terra_raster)[[2]][["filetype"]] <- filetype
+ body(.write_terra_raster)[[2]][["gdal"]] <- gdal
+
+ targets::tar_format(
+ read = function(path) terra::rast(path),
+ write = .write_terra_raster,
+ marshal = function(object) terra::wrap(object),
+ unmarshal = function(object) terra::unwrap(object)
+ )
+}
+