Merge pull request #107 from R-ArcGIS/truncate

add truncate support

NEWS.md

@@ -1,5 +1,6 @@
 # arcgislayers 0.1.0 (unreleased)
 
+- Add `truncate_layer()` to support truncate and append workflow
 - Add support for opening `MapServers` <https://github.com/R-ArcGIS/arcgislayers/pull/83>
 - `arc_open()` with a layer that does not support `Query` sets the `n` attribute to`NA` <https://github.com/R-ArcGIS/arcgislayers/pull/83>
  - Print method will show something like `<FeatureLayer <NA features, 10 fields>>`

R/truncate.R

@@ -0,0 +1,84 @@
+#' Truncate a Feature Layer
+#'
+#' Removes all features in a Feature Layer or Table and resets the object ID
+#' counter. Truncating a Feature Layer does not change the schema of the data
+#' (does not add, remove, or alter existing database columns, constraints,
+#' or indexes).
+#'
+#' @inheritParams arc_select
+#' @param async default `FALSE`. It is recommended to set `TRUE` for
+#' larger datasets.
+#' @param attachment_only default `FALSE`. Deletes all the attachments for this
+#' layer. None of the layer features will be deleted when `TRUE`.
+#' @references [ArcGIS Developers Rest API Doc](https://developers.arcgis.com/rest/services-reference/online/truncate-feature-layer-.htm)
+#'
+#' @returns a named list with the name "success" and a value of `TRUE` or `FALSE`
+#'
+#' @examples
+#' \donttest{
+#' if (interactive()) {
+#'
+#' # authorize using code flow
+#' set_auth_token(auth_code())
+#'
+#' # create a FeatureLayer object
+#' flayer <- arc_open("your-feature-layer-url")
+#'
+#' # truncate it
+#' truncate_layer(flayer)
+#' }
+#' }
+truncate_layer <- function(
+ x,
+ async = FALSE,
+ attachment_only = FALSE,
+ token = Sys.getenv("ARCGIS_TOKEN")
+) {
+
+ # check to see if it is a compatible class
+ obj_check_layer(x)
+
+ # ensure that it supports truncate
+ if (!x[["supportsTruncate"]]) {
+ obj <- rlang::caller_arg(x)
+ cli::cli_abort(
+ "{.arg {obj}} does not support the {.code truncate } operation"
+ )
+ }
+
+ # extract url and its components
+ furl <- x[["url"]]
+ parts <- httr2::url_parse(furl)
+
+ # replace /services/ with /admin/services/
+ parts[["path"]] <- sub("\\/services/", "/admin/services/", parts[["path"]])
+
+ # rebuild the url
+ burl <- httr2::url_build(parts)
+
+ # create the base request
+ b_req <- httr2::req_url_path_append(
+ httr2::request(burl),
+ "truncate"
+ )
+
+ # create the request
+ req <- httr2::req_body_form(
+ b_req,
+ f = "json",
+ async = async,
+ attachmentOnly = attachment_only
+ )
+
+ # perform request
+ resp <- httr2::req_perform(
+ # add the token
+ httr2::req_auth_bearer_token(req, token)
+ )
+
+ res_string <- httr2::resp_body_string(resp)
+
+ res <- RcppSimdJson::fparse(res_string)
+ detect_errors(res)
+ res
+}