fn dbpedia_get_wikidata_uris()

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: dbpedia
 Type: Package
 Title: R wrapper for DBpedia Spotlight
-Version: 0.0.1.9001
+Version: 0.0.1.9002
 Date: 2023-09-21
 Authors@R: c(
   person("Andreas", "Blaette", role = c("aut", "cre"), email = "andreas.blaette@uni-due.de", comment = c(ORCID = "0000-0001-8970-8010")),
@@ -21,7 +21,8 @@ Imports:
 Suggests:
     markdown (>= 1.5),
     rmarkdown,
-    knitr
+    knitr,
+    SPARQL
 VignetteBuilder: knitr
 SystemRequirements: docker
 LazyData: true
@@ -34,6 +35,7 @@ Encoding: UTF-8
 Collate: 
     'dbpedia.R'
     'utils.R'
+    'wikidata.R'
     'zzz.R'
 Roxygen: list(markdown = TRUE)
 RoxygenNote: 7.2.3

NAMESPACE

@@ -6,8 +6,10 @@ import(methods)
 importFrom(RcppCWB,cl_struc2str)
 importFrom(cli,cli_alert_danger)
 importFrom(cli,cli_alert_warning)
+importFrom(cli,cli_progress_bar)
 importFrom(cli,cli_progress_done)
 importFrom(cli,cli_progress_step)
+importFrom(cli,cli_progress_update)
 importFrom(data.table,`:=`)
 importFrom(data.table,as.data.table)
 importFrom(data.table,setDT)

R/wikidata.R

@@ -0,0 +1,87 @@
+#' Get Wikipedia IDs for DBpedia IDS.
+#' 
+#' @param x A character vector with DBpedia URIs.
+#' @param optional Optional information to retrieve (passed as length-one
+#'   character vector, e.g. 'municipalityCode').
+#' @param endpoint Endpoint to query (a `character` vector).
+#' @param limit Single numeric value with maximum size of chunks to process at
+#'   a time.
+#' @param wait A numeric value passed into `Sys.sleep()` to slow down sequence
+#'   of requests (and avoid denial of service). Defaults to 100.
+#' @param progress Whether to show progress bar (`logical` value).
+#' @examples
+#' \donttest{
+#' dbpedia_ids <- c(
+#'   "http://de.dbpedia.org/resource/Killesberg",
+#'   "http://de.dbpedia.org/resource/Ljubljana",
+#'   "http://de.dbpedia.org/resource/Velbert"
+#' )
+#' dbpedia_get_wikidata_uris(
+#'   dbpedia_ids,
+#'   optional = "municipalityCode",
+#'   endpoint = "http://de.dbpedia.org/sparql",
+#'   wait = 0,
+#'   limit = 2,
+#'   progress = TRUE
+#' )
+#' }
+#' @importFrom cli cli_progress_bar cli_progress_done cli_progress_update
+dbpedia_get_wikidata_uris <- function(x, optional, endpoint, limit = 100, wait = 1, progress = FALSE){
+
+  if (!requireNamespace("SPARQL", quietly = TRUE)){
+    stop(
+      "R package SPARQL required but not available. ",
+      "SPARQL is currently not at CRAN, but can be installed from the archive"
+    )
+  }
+
+  stopifnot(
+    is.character(x),
+    is.numeric(limit), length(limit) == 1L,
+    is.logical(progress), length(progress) == 1L,
+    is.numeric(wait), length(wait) == 1L, wait >= 0
+  )
+
+  if (!missing(optional)){
+    stopifnot(is.character(optional), length(optional) == 1L)
+    optional <- sprintf('OPTIONAL { ?item dbo:%s ?key . }', optional)
+  } else {
+    optional <- ""
+  }
+
+  template <- 'SELECT distinct ?item ?wikidata_uri ?key
+      WHERE {
+      VALUES ?item {%s}
+      ?item owl:sameAs ?wikidata_uri
+      %s
+      FILTER(regex(str(?wikidata_uri), "www.wikidata.org" ) )}
+      LIMIT %d'
+
+
+  chunks <- as_chunks(x = x, size = limit)
+  retval_li <- list()
+
+  if (progress) cli_progress_bar("Tasks", total = length(chunks), type = "tasks")
+  for (i in 1L:length(chunks)){
+    cli_progress_update()
+    query <- sprintf(
+      template,
+      paste(sprintf("<%s>", chunks[[i]]), collapse = " "),
+      optional,
+      limit
+    )
+
+    Sys.sleep(wait)
+
+    retval_li[[i]] <- SPARQL::SPARQL(url = endpoint, query = query)[["results"]]
+    retval_li[[i]][["wikidata_id"]] <- gsub(
+      "^.*\\/(Q\\d+)>$", "\\1",
+      retval_li[[i]][["wikidata_uri"]]
+    )
+    colnames(retval_li[[i]])[1] <- "dbpedia_uri"
+  }
+
+  if (progress) cli_progress_done()
+
+  do.call(rbind, retval_li)
+}