R/guess_member_node.R

In NCEAS/datamgmt: Data Management Utilities for Curating, Documenting, and Publishing Data

#' Guess the Member Node
#'
#' Guess the Member Node that stores a DataONE object based on its
#' unique identifier (\code{pid}) and coordinating node (\code{cn}). In most cases
#' the object is stored on the Production ("PROD") Node, however this function can
#' search across all coordinating nodes. If only one Member Node is identified this
#' function returns the Member Node as a DataONE "MNode" object. If multiple Member
#' Nodes are identified a vector of nodes is printed.
#'
#' @param pid (character) The DataONE unique object identifier.  A DataONE package URL can also be used as input
#'   (although this method is less reliable).
#' @param cn (character) A character vector of coordinate nodes to search.  Defaults to "PROD".
#'   Can be set to any combination of ("PROD", "STAGING", "STAGING2", "SANDBOX", "SANDBOX2", "DEV", "DEV2").
#'
#' @export
#'
#' @author Dominic Mullen, \email{dmullen17@@gmail.com}
#'
#' @examples
#' \dontrun{
#' The following two calls are equivalent:
#' mn <- guess_member_node("doi:10.18739/A2G287")
#' mn <- guess_member_node("doi:10.18739/A2G287", "PROD")
#'
#' Use a DataONE package URL
#' mn <- guess_member_node("https://arcticdata.io/catalog/#view/doi:10.18739/A2TX35587")
#' Search all coordinating nodes:
#' cn <- c("PROD", "STAGING", "STAGING2", "SANDBOX", "SANDBOX2", "DEV", "DEV2")
#' mn <- guess_member_node("doi:10.18739/A2G287", cn)
#' }
#'
guess_member_node <- function(pid, cn = "PROD") {
    stopifnot(is.character(pid))
    stopifnot(is.character(cn))
    stopifnot(all(cn %in% c("PROD", "STAGING", "STAGING2", "SANDBOX", "SANDBOX2", "DEV", "DEV2")))

    if (grepl("view/", pid)) {
        pid <- unlist(strsplit(pid, "view/"))[[2]]
    }

    query_datasource <- function(cn, pid) {
        cn <- dataone::CNode(cn)
        q <- unlist(dataone::query(cn,
                                   paste0("q=identifier:\"",
                                          pid,
                                          "\"&fl=datasource")))
    }

    results <- unlist(sapply(cn, query_datasource, pid = pid))

    if (length(results) == 0) {
        stop(paste0("Identifier not found in node: ", cn, "\n"))
    }

    if (length(results) > 1) {
        message("Identifier found on multiple nodes:\n")
        print(results)
        return()
    }

    # remove '.datasource' from names(results) to isolate cn names
    cn <- gsub("\\.datasource", "", names(results))
    cn <- dataone::CNode(cn)
    mn <- dataone::getMNode(cn, results)

    return(mn)
}