R/series_bacen.R

In fernote7/series.bacen: An R Interface to Brazilian Central Bank and Sidra APIs and the IPEA Data

#' A function to extract BACEN series using their API
#' @param x Bacen series numbers. Either an integer or a numeric vector.
#' @param from A string specifying where the series shall start.
#' @param to A string specifying where the series shall end.
#' @param save A string specifying if data should be saved in csv or xlsx format. 
#' Defaults to not saving.
#' @keywords bacen
#' @export
#' @import RCurl 
#' @importFrom readr read_csv write_csv
#' @examples 
#' bacen = series_bacen(x=c(2465, 1242))

series_bacen <- function(x, from = "", to = "", save = ""){
    
    
    if (missing(x)){
        stop("Need to specify at least one serie.")
    }
    
    if (! is.numeric(x)){
        stop("x must be numeric")
    }
    
    if (from == ""){
        data_init = "01/01/1980"
    } else {data_init = from}
    
    if (to == ""){
        data_end = format(Sys.Date(), "%d/%m/%Y")
    } else {data_end = to}
    
    inputs = as.character(x)
    len = seq_along(inputs)
    serie = mapply(paste0, "serie_", inputs, USE.NAMES = FALSE)
    
    
     for (i in len){
        result = tryCatch({
            
        RCurl::getURL(paste0('http://api.bcb.gov.br/dados/serie/bcdata.sgs.',
                              inputs[i], 
                             '/dados?formato=csv&dataInicial=', data_init, '&dataFinal=',
                              data_end),
                              ssl.verifyhost=FALSE, ssl.verifypeer=FALSE, 
                              .opts = list(timeout = 1, maxredirs = 2))
        },
        error = function(e) {
            return(RCurl::getURL(paste0('http://api.bcb.gov.br/dados/serie/bcdata.sgs.',
                                        inputs[i], 
                                        '/dados?formato=csv&dataInicial=', data_init,
                                        '&dataFinal=',
                                        data_end),
                                        ssl.verifyhost=FALSE, ssl.verifypeer=FALSE))
            
        })
        
        assign(serie[i], result) 
    }
    
    rm(result)
    
    
    for (i in len) {
        tryCatch({
            texto = readr::read_csv2(eval(as.symbol(serie[i])), 
                                    col_names = T)
            texto$data = gsub(" .*$", "", eval(texto$data))
            assign(serie[i], texto)
        }, error = function(cond) {
            message(paste(serie[i], 
                          "could not be downloaded due to BCB server instability."))
        })
    }
    rm(texto)
    
    
    if (save != ""){
        if (save == "csv"){
            for(i in len) {readr::write_csv(eval(as.symbol(serie[i])), 
                                            path = paste0(serie[i], ".csv"))}
        } 
    
    if (requireNamespace("xlsx", quietly = TRUE)) {        
        if (save == "xls" | save == "xlsx") {
            for(i in len) {xlsx::write.xlsx(eval(as.symbol(serie[i])), 
                                      file = paste0(serie[i], ".xlsx"), 
                                      row.names = FALSE)}} else{ 
                                          stop("save argument must be 'csv' or 'xlsx' ")}
        }
    }
    
    lista = list()
    ls_df = ls()[grepl('data.frame', sapply(ls(), function(x) class(get(x))))]
    for ( obj in ls_df ) { lista[obj]=list(get(obj)) }
    
    return(invisible(lista))
    
}