R/FILTERING-post_smiles.R

In NIVANorge/chemspiderapi: R Wrapper for ChemSpider's API Services

#' @title Post a SMILES string
#' @description Functionality to post a SMILES string to obtain a \code{queryId} for use in \code{chemspiderapi::get_queryID_status()} and \code{chemspiderapi::get_queryId_results()}.
#' @details If successful, returns the \code{queryId} as character string.
#' @param smiles A SMILES character string.
#' @param apikey A 32-character string with a valid key for ChemSpider's API services.
#' @param coerce \code{logical}: should the list be coerced to a data.frame? Defaults to \code{FALSE}.
#' @param simplify \code{logical}: should the results be simplified to a vector? Defaults to \code{FALSE}.
#' @return Returns the queryId string as (named) character vector.
#' @seealso \url{https://developer.rsc.org/compounds-v1/apis/post/filter/smiles}
#' @examples \dontrun{
#' ## post the SMILES string of caffeine to get a queryId
#' smiles <- "Cn1cnc2c1c(=O)n(c(=O)n2C)C"
#' apikey <- "a valid 32-character ChemSpider apikey"
#' post_smiles(smiles = smiles, apikey = apikey)
#' }
#' @importFrom curl curl_fetch_memory handle_setheaders handle_setopt new_handle
#' @importFrom jsonlite fromJSON toJSON
#' @export
post_smiles <- function(smiles, apikey, coerce = FALSE, simplify = FALSE) {
  
  .check_smiles(smiles)
  
  .check_apikey(apikey)
  
  .check_coerce(coerce)
  
  .check_simplify(simplify)
  
  data <- list("smiles" = smiles)
  data <- jsonlite::toJSON(data, auto_unbox = TRUE)
  
  header <- list("Content-Type" = "", "apikey" = apikey)
  
  url <- Sys.getenv("POST_SMILES_URL", 
                    "https://api.rsc.org/compounds/v1/filter/smiles")
  
  handle <- curl::new_handle()
  
  curl::handle_setopt(handle, customrequest = "POST", postfields = data)
  
  curl::handle_setheaders(handle, .list = header)
  
  raw_result <- curl::curl_fetch_memory(url = url, handle = handle)
  
  .check_status_code(raw_result$status_code)
  
  result <- rawToChar(raw_result$content)
  result <- jsonlite::fromJSON(result)
  
  if (coerce) {
    result <- as.data.frame(result, stringsAsFactors = FALSE)
  }
  
  if (simplify) {
    result <- unlist(result, use.names = FALSE)
  }
  
  result
}