R/bea2List.r

In us-bea/bea.R: Bureau of Economic Analysis API

#' Convert BEA API httr response payload to list
#'
#' @param beaPayload An object with httr class 'response' from call to BEA API
#' @param isMeta 	 Special parameter meant to interact with metadata functions (default: FALSE)
#' @return An object of class 'list' of several dimensions. View list structure using 'str(yourList)'.
#' @import httr
#' @importFrom jsonlite fromJSON
#' @export
#' @examplesIf interactive()  && Sys.getenv("BEA_API_KEY") != ""
#' userSpecList <- list('UserID' = Sys.getenv("BEA_API_KEY"),
#'									'Method' = 'GetData',
#'									'datasetname' = 'NIPA',
#'									'Frequency' = 'A',
#'									'TableName' = 'T20405',
#'									'Year' = 'X')
#' resp <- beaGet(userSpecList, asTable = FALSE)
#' BL <- bea2List(resp)


bea2List <- function(beaPayload, isMeta=FALSE) {
	requireNamespace('httr', quietly = TRUE)
	requireNamespace('jsonlite', quietly = TRUE)

	if(!inherits(beaPayload, 'response') && !inherits(beaPayload, 'character')){
		stop('Submitted variable is not a valid JSON string or httr response class object.', call.=TRUE)
	}

  if(inherits(beaPayload, 'response')){
  	if(floor(beaPayload$status_code/100) != 2){
  		stop(
  			paste0('Request failed. Returned HTTP status code: ', beaPayload$status_code),
  			call. = TRUE
  		)
  	}

    #Never going to fix later: I gave up on parsing it identically and just re-pull data as JSON.
  		if(length(grep("resultformat=xml", beaPayload$url, ignore.case=TRUE))==1){
  			beaJSON <- httr::GET(
  				gsub(
  					"resultformat=xml",
  					"ResultFormat=json",
  					beaPayload$url,
  					ignore.case=TRUE
  				)
  			)

  			beaContent <- httr::content(beaJSON, as = 'text', encoding = 'UTF-8')
  		}
  		else {
  			beaContent <- httr::content(beaPayload, as = 'text', encoding = 'UTF-8')
  		}
  } else {
      beaContent <- beaPayload
  }

	beaResponse <- jsonlite::fromJSON(beaContent)
  if(!is.element('BEAAPI', names(beaResponse))){
    stop(paste0('The submitted request was not a valid BEA API response: ', beaContent), call.=TRUE)
  }
	#Handler for certain dataset responses having a different structure >:(
	if(inherits(beaResponse$BEAAPI$Results, 'data.frame')){
	  beaResponse$BEAAPI$Results <- as.list(beaResponse$BEAAPI$Results)
	  beaResponse$BEAAPI$Results$Dimensions <- as.data.frame(beaResponse$BEAAPI$Results$Dimensions)
	  beaResponse$BEAAPI$Results$Notes <- as.data.frame(beaResponse$BEAAPI$Results$Notes)
	  beaResponse$BEAAPI$Results$Data <- as.data.frame(beaResponse$BEAAPI$Results$Data)
	}

	if('error' %in% tolower(
		attributes(
			beaResponse$BEAAPI$Results
		)$names)
	){
		warning(beaResponse$BEAAPI$Results$Error$APIErrorDescription)
		return(beaResponse$BEAAPI$Results)
	}

	if(isMeta){
		beaList <- beaResponse$BEAAPI$Results
		attributes(beaList)$params <- beaResponse$BEAAPI$Request$RequestParam
	} else {
		beaList <- beaResponse$BEAAPI$Results$Data
		attributes(beaList)$params <- beaResponse$BEAAPI$Request$RequestParam
		attributes(beaList)$detail <- beaResponse$BEAAPI$Results[(
			attributes(beaResponse$BEAAPI$Results)$names != 'Data'
		)]
		beaList$DataValue <- as.numeric(
			gsub(',', '',  beaList$DataValue, fixed = TRUE)
		)
	}

	#Use jsonlite fromJSON f(x) to convert to list
	return(beaList)
}