R/getSymbols.R

In quantmod: Quantitative Financial Modelling Framework

# getSymbols {{{
"getSymbols" <-
function(Symbols=NULL,
         env=parent.frame(),  ### 0.4-0
         #env=NULL,          ### 0.5-0
         reload.Symbols=FALSE,
         verbose=FALSE,
         warnings=TRUE,
         src="yahoo",
         symbol.lookup=TRUE,
         auto.assign=getOption('getSymbols.auto.assign',TRUE),
         ...)  {

      importDefaults("getSymbols")
      #  to enable as-it-was behavior, set this:
      #  options(getSymbols=list(env=substitute(parent.frame(3))))

      #if(missing(env))
      #  env <- eval(getOption("getSymbols")$env)    ### 0.5-0

      if(missing(env) && !is.null(getOption("getSymbols.env")) )
          env <- getOption("getSymbols.env")         ### 0.4-0

      #env_ <- getSymbols_options_("env")
      #if(missing(env) && !is.null(env_))
      #  env <- env_
      if(is.null(env)) # default as of 0.5-0
        auto.assign <- FALSE
      if(!auto.assign && length(Symbols)>1)
        stop("must use auto.assign=TRUE for multiple Symbols requests")
      force(Symbols)  # need to check if symbol lookup defined _within_ call
      if(symbol.lookup && missing(src)) {
        # if src is specified - override symbol.lookup
        symbols.src <- getOption('getSymbols.sources')
      } else {
        symbols.src <- src[1]
      }
      #src <- src[1]
      if(is.character(Symbols)) {
      # at least one Symbol has been specified
        Symbols <- unlist(strsplit(Symbols,';'))
        tmp.Symbols <- vector("list")
        for(each.symbol in Symbols) {
          if(each.symbol %in% names(symbols.src)) {
            tmp.src <- symbols.src[[each.symbol]]$src[1]
            #tmp.src <- symbols.src[[each.symbol]]
            if(is.null(tmp.src)) {
              tmp.Symbols[[each.symbol]] <- src[1]
            } else {
              tmp.Symbols[[each.symbol]] <- tmp.src
            }
          } else {
            tmp.Symbols[[each.symbol]] <- src[1]
          }
        }
        Symbols <- tmp.Symbols
      }
      old.Symbols <- NULL
      if(auto.assign && exists('.getSymbols',env,inherits=FALSE)) {
        old.Symbols <- get('.getSymbols',env)
      }
      if(reload.Symbols) {
        Symbols <- c(Symbols, old.Symbols)[unique(names(c(Symbols,old.Symbols)))]
      }
      if(!auto.assign && length(Symbols) > 1)
        stop("must use auto.assign=TRUE when reloading multiple Symbols")
      if(!is.null(Symbols)) {
        #group all Symbols by source
        Symbols <- as.list(unlist(lapply(unique(as.character(Symbols)),
                           FUN=function(x) {
                             Symbols[Symbols==x]
                           }
                           )))
        # are any symbols reserved words?
        if(getOption("quantmod.warn.ticker.reserved.word", TRUE)) {
          reserved.tickers <- c("NA", "TRUE")
          is.reserved <- reserved.tickers %in% names(Symbols)
          if(any(is.reserved)) {
            rtk <- paste(reserved.tickers[is.reserved], collapse = ", ")
            if (sum(is.reserved) > 1) {
              msg <- paste("tickers", rtk, "are reserved words")
            } else {
              msg <- paste("ticker", rtk, "is a reserved word")
            }
            warning(msg, " and must be back-quoted to be used (e.g. `NA`).")
          }
        }

        # was getSymbols() called with more than 1 symbol?
        .has1sym. <- length(Symbols) < 2L
        #Symbols <- as.list(Symbols)
        all.symbols <- list()
        for(symbol.source in unique(as.character(Symbols))) {
          current.symbols <- names(Symbols[Symbols==symbol.source])
          symbols.returned <- do.call(paste('getSymbols.',symbol.source,sep=''),
                                      list(Symbols=current.symbols,env=env,
                                           #return.class=return.class,
                                           #reload.Symbols=reload.Symbols,
                                           verbose=verbose,warnings=warnings,
                                           auto.assign=auto.assign,
                                           ...,
                                           .has1sym.=.has1sym.))
          if(!auto.assign)
            return(symbols.returned)
          for(each.symbol in symbols.returned) all.symbols[[each.symbol]] <- symbol.source
        }
        req.symbols <- names(all.symbols)
        all.symbols <- c(all.symbols,old.Symbols)[unique(names(c(all.symbols,old.Symbols)))]
        if(auto.assign) {
          assign('.getSymbols',all.symbols,env);
          return(req.symbols)
          #return(env)
        }
      } else {
        warning('no Symbols specified')
      }
}
#}}}

loadSymbols <- getSymbols
loadSymbols.formals <- c(formals(getSymbols)[-(8:9)], alist(auto.assign=getOption("loadSymbols.auto.assign",TRUE),...=))
formals(loadSymbols) <- loadSymbols.formals


# getSymbols.Bloomberg {{{
#"getSymbols.Bloomberg" <- function(Symbols,env,return.class='xts',
#                              from=as.POSIXlt(Sys.time()-60*60,"GMT"),
#                              to=as.POSIXlt(Sys.time(),"GMT"),
#                              bb.suffix="Equity",
#                              bb.interval="5",
#                              ...) {
#    importDefaults("getSymbols.Bloomberg")
#    this.env <- environment()
#    for(var in names(list(...))) {
#       # import all named elements that are NON formals
#       assign(var, list(...)[[var]], this.env)
#    }
#    if ((class(from)=="Date" && class(to)=="Date") ||
#           (class(from)=="character" && length(from)<=8 &&
#               class(to)=="character" && length(to)<=8 )) {
#       bb.intraday <- FALSE
#       bb.call <- bdh
#       bb.fields <- c("OPEN", "HIGH", "LOW", "PX_LAST", "VOLUME")
#    } else {
#       bb.intraday <- TRUE
#       bb.call <- bar
#       bb.fields <- "TRADE"
#    }
#    if(missing(verbose)) verbose <- FALSE
#    if(missing(auto.assign)) auto.assign <- TRUE
#       if('package:RBloomberg' %in% search() ||
#require('RBloomberg',quietly=TRUE)) {
#         {}
#       } else {
#         stop(paste("package:",dQuote('RBloomberg'),"cannot be loaded."))
#       }
#       bbconn <- blpConnect()
#       for(i in 1:length(Symbols)) {
#           bbsym <- paste(Symbols[[i]],bb.suffix)
#
#           if(verbose) {
#               cat(paste('Loading ',bbsym, ' from BB ', from,' to ',to,
#                   paste(rep('.',18-nchar(Symbols[[i]])),collapse=''),
#                   sep=''))
#
#           }
#           tryCatch (
#             {
#               if (bb.intraday) {
#                 fromStr <- paste(as.character(from),".000",sep="")
#                 toStr <- paste(as.character(to),".000",sep="")
#                 b <- bb.call(bbconn, bbsym, bb.fields,
#                             fromStr, toStr, bb.interval)
#                 b$datetime <- as.POSIXct(strptime(b$time,
#format="%Y-%m-%dT%H:%M:%S"))
#                 bxo <- as.xts(b$open, order.by=b$datetime)
#                 fr <- merge(bxo,  b$high, b$low, b$close, b$volume)
#               } else {
#                 if (class(from)=="character") {
#                   fromStr <- from
#                 } else {
#                   fromStr <- strftime(from,format="%Y%m%d")
#                 }
#                 if (class(to)=="character") {
#                   toStr <- to
#                 } else {
#                   toStr <- strftime(to,format="%Y%m%d")
#                 }
#                 b <- bb.call(bbconn, bbsym, bb.fields,
#                             fromStr, toStr)
#                 b$datetime <- as.POSIXct(strptime(b$date,
#format="%Y-%m-%d"))
#                 bxo <- as.xts(b$OPEN, order.by=b$datetime)
#                 fr <- merge(bxo,  b$HIGH, b$LOW, b$PX_LAST, b$VOLUME)
#               }
#
#
#
#               if(verbose) {
#                 cat(paste(length(fr),'points '))
#               }
#               colnames(fr) <- paste(Symbols[[i]],
#                                     c('Open','High','Low','Close','Volume'),
#                                     sep='.')
#               fr <- convert.time.series(fr=fr,return.class=return.class)
#               if(auto.assign)
#                 assign(Symbols[[i]],fr,env)
#             },
#             error=function(e) {print(e);fr <- data.frame()},
#             finally=function () {if(verbose) {cat('done\n')}}
#           )
#       }
#       blpDisconnect(bbconn)
#       if(auto.assign)
#         return(Symbols)
#       return(fr)
#}
#"getSymbols.Bloomberg" <- getSymbols.Bloomberg
# }}}

.getHandle <- function(curl.options = list(), force.new = FALSE)
{
  h <- get0("_handle_", .quantmodEnv)

  if (is.null(h) || force.new) {
    # create 'h' if it doesn't exist yet
    h <- curl::new_handle()
    curl::handle_setopt(h, .list = curl.options)

    assign("_handle_", h, .quantmodEnv)
  }
  return(h)
}

.yahooJsonURL <-
function(symbol, from, to, interval)
{
  u <- paste0("https://query2.finance.yahoo.com/v8/finance/chart/",
              symbol,
              sprintf("?period1=%.0f&period2=%.0f&interval=%s", from, to, interval))
  return(u)
}

.dateToUNIX <- function(Date) {
  posixct <- as.POSIXct(as.Date(Date, origin = "1970-01-01"))
  trunc(as.numeric(posixct))
}

# getSymbols.yahoo {{{
"getSymbols.yahoo" <-
function(Symbols,env,return.class='xts',index.class="Date",
         from='2007-01-01',
         to=Sys.Date(),
         ...,
         periodicity="daily",
         curl.options=list())
{
     importDefaults("getSymbols.yahoo")
     this.env <- environment()
     for(var in names(list(...))) {
        # import all named elements that are NON formals
        assign(var, list(...)[[var]], this.env)
     }
     if(!hasArg("adjust"))
       adjust <- FALSE

     default.return.class <- return.class
     default.from <- from
     default.to <- to

     mins <- c(1, 2, 5, 15, 30, 60, 90)
     min_vals <- paste0(rep(mins, 2), "m")
     names(min_vals) <- c(paste0(mins, "minutes"), paste0(mins, " minutes"))

     intervals <- c(daily = "1d", weekly = "1wk", monthly = "1mo", hourly = "1h", min_vals)

     default.periodicity <- match.arg(periodicity, names(intervals))

     if(!hasArg("verbose")) verbose <- FALSE
     if(!hasArg("auto.assign")) auto.assign <- TRUE
     if(!hasArg("warnings")) warnings <- TRUE

     handle <- .getHandle(curl.options)

     returnSym <- Symbols
     noDataSym <- NULL
     for(i in seq_along(Symbols)) {
       test <- try({
       return.class <- getSymbolLookup()[[Symbols[[i]]]]$return.class
       return.class <- ifelse(is.null(return.class),default.return.class,
                              return.class)
       periodicity <- getSymbolLookup()[[Symbols[[i]]]]$periodicity
       periodicity <- if(is.null(periodicity)) default.periodicity else periodicity

       # ensure valid periodicity
       p <- pmatch(periodicity, names(intervals))
       if(is.na(p))
         stop("periodicity must be one of: ", paste(intervals, collapse=", "))
       interval <- intervals[p]

       is.intraday <- !(interval %in% c("1d", "1wk", "1mo"))

       from <- getSymbolLookup()[[Symbols[[i]]]]$from
       from <- if(is.null(from)) default.from else from
       to <- getSymbolLookup()[[Symbols[[i]]]]$to
       to <- if(is.null(to)) default.to else to

       if(is.intraday) {
         from.date <- as.Date(from)
         to.date <- as.Date(to)
         n.days <- difftime(time1 = to.date, time2 = from.date, units = "days")
         if(n.days > 7) {
           from <- to.date - 7
           if(warnings) {
             warning(paste0(
               "Only a maximum of 7 days is allowed for querying intraday data",
               "data from 'yahoo'. Setting `from` to '", from, "'."
             ), call. = FALSE)
           }
         }
       }

       from.posix <- .dateToUNIX(from)
       to.posix <- .dateToUNIX(to)

       Symbols.name <- getSymbolLookup()[[Symbols[[i]]]]$name
       Symbols.name <- ifelse(is.null(Symbols.name),Symbols[[i]],Symbols.name)
       if(verbose) cat("downloading ",Symbols.name,".....\n\n")

       yahoo.URL <- .yahooJsonURL(Symbols.name, from.posix, to.posix, interval)
       conn <- curl::curl(yahoo.URL, handle = handle)
       y <- jsonlite::fromJSON(conn)
       if (is.null(y$chart) || is.null(y$chart$result)) {
         stop("no data for", Symbols.name)
       }
       y <- y$chart$result

       ohlcv <- unlist(y$indicators$quote[[1]], recursive = FALSE)

       tz <- y$meta$exchangeTimezoneName
       idx <- .POSIXct(y$timestamp[[1]], tz = tz)
       if (!is.intraday) {
         idx <- as.Date(idx)
       }

       x <- xts(do.call(cbind, ohlcv), idx,
                 src='yahoo', updated=Sys.time())

       fr <- OHLCV(x)
       cnames <- c("Open", "High", "Low", "Close", "Volume")
       if (!is.intraday) {
         fr <- merge(fr, adjusted = unlist(y$indicators$adjclose))
         cnames <- c(cnames, "Adjusted")
       }

       # convert column names to Initial Capitalization
       cn <- colnames(fr)
       substring(cn, 1, 1) <- toupper(substring(cn, 1, 1))
       colnames(fr) <- cn

       # warn about missing values
       if (any(is.na(fr)) && isTRUE(warnings)) {
         warning(Symbols.name, " contains missing values. Some functions will",
                 " not work if objects contain missing values in the middle",
                 " of the series. Consider using na.omit(), na.approx(),",
                 " na.fill(), etc to remove or replace them.", call. = FALSE)
       }

       # re-order column names and prefix with symbol
       corder <- pmatch(substr(cnames, 1, 3), colnames(fr))
       fr <- fr[,corder]
       colnames(fr) <- paste(toupper(gsub("\\^","",Symbols.name)), cnames, sep=".")

       if(adjust) {
         # Adjustment algorithm by Joshua Ulrich
         fr <- adjustOHLC(fr, symbol.name=Symbols.name)
       }

       fr <- convert.time.series(fr=fr,return.class=return.class)
       if(is.xts(fr)) {
         if(!is.intraday) {
           tclass(fr) <- index.class
         }
       }

       Symbols[[i]] <- toupper(gsub('\\^','',Symbols[[i]]))
       returnSym[[i]] <- gsub('\\^', '', returnSym[[i]])

       if(auto.assign)
         assign(Symbols[[i]],fr,env)
       }, silent = TRUE)
       if (inherits(test, "try-error")) {
         msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                       ".\n", attr(test, "condition")$message)
         if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
           stop(msg)
         }
         if (isTRUE(warnings)) {
           warning(msg, call. = FALSE, immediate. = TRUE)
         }
         noDataSym <- c(noDataSym, returnSym[[i]])
       }
     }
     if(auto.assign)
       return(setdiff(returnSym, noDataSym))
     return(fr)
}
# }}}

# getSymbols.yahooj {{{
"getSymbols.yahooj" <-
    function(Symbols, env=parent.frame(), return.class='xts', index.class="Date",
             from='2007-01-01',
             to=Sys.Date(),
             ...)
    {
        importDefaults("getSymbols.yahooj")
        this.env <- environment()
        for(var in names(list(...))) {
            # import all named elements that are NON formals
            assign(var, list(...)[[var]], this.env)
        }
        if(!hasArg("adjust"))
            adjust <- FALSE

        default.return.class <- return.class
        default.from <- from
        default.to <- to

        if(!hasArg("verbose")) verbose <- FALSE
        if(!hasArg("auto.assign")) auto.assign <- TRUE
        if(!hasArg("warnings")) warnings <- TRUE

        if(!requireNamespace("xml2", quietly=TRUE))
          stop("package:",dQuote("xml2"),"cannot be loaded.")

        yahoo.URL <- "https://finance.yahoo.co.jp/quote/"

        returnSym <- Symbols
        noDataSym <- NULL
        for(i in seq_along(Symbols)) {
            test <- try({
            # The name of the symbol, which will actually be used as the
            # variable name. It needs to start with YJ, and it will be appended
            # if it does not.
            symname <- toupper(Symbols[[i]])

            # The symbol actually sent to Yahoo Japan. This is without the
            # starting YJ bit.
            symbol <- symname

            # If it starts with YJ, try looking up defaults
            if (grepl("^YJ", symname)) {
                return.class <- getSymbolLookup()[[symname]]$return.class
                return.class <- ifelse(is.null(return.class),default.return.class,
                                       return.class)
                from <- getSymbolLookup()[[symname]]$from
                from <- if(is.null(from)) default.from else from
                to <- getSymbolLookup()[[symname]]$to
                to <- if(is.null(to)) default.to else to

                # Extract the actual symbol to be sent to Yahoo Japan
                symbol <- substring(symname, 3)
            } else {
                return.class <- default.return.class
                from <- default.from
                to <- default.to

                # Prepend 'YJ' to the symbol and store it in symname
                symname <- paste('YJ', symbol, sep="")
            }

            from.str <- format(as.Date(from), "%Y%m%d")
            to.str <- format(as.Date(to), "%Y%m%d")

            Symbols.name <- getSymbolLookup()[[symname]]$name
            Symbols.name <- ifelse(is.null(Symbols.name),symbol,Symbols.name)
            if(verbose) cat("downloading ",Symbols.name,".....\n\n")

            page <- 1
            totalrows <- c()
            while (TRUE) {
                URL <- paste0(yahoo.URL, Symbols.name, "/history?")
                URL <- paste0(URL, "from=", from.str, "&to=", to.str, "&timeFrame=d&page=", page)

                fdoc <- xml2::read_html(URL)

                rows <- xml2::xml_find_all(fdoc, "//table/tbody/tr")
                rows <- lapply(rows, function(r) { xml2::xml_text(xml2::xml_children(r)) })
                rows <- rows[sapply(rows, length) >= 5]

                if (length(rows) == 0) break

                totalrows <- c(totalrows, rows)
                page <- page + 1
            }
            if(verbose) cat("done.\n")

            if (is.null(rows)) {
              stop("No historical data for ", dQuote(Symbols[[i]]), ".")
            }

            # Available columns
            cols <- c('Open','High','Low','Close','Volume','Adjusted')

            # Handle date + OHLC, when date + OHLCVA isn't returned
            if (length(totalrows[[1]]) == 5) {
              cols <- cols[-(5:6)]
            }

            # Process from the start, for easier stocksplit management
            totalrows <- rev(totalrows)

            mat <- do.call(rbind, totalrows)

            dates <- as.Date(mat[,1], format="%Y\u5e74%m\u6708%d\u65e5")
            ohlc <- gsub(",", "", mat[,-1], fixed = TRUE)
            storage.mode(ohlc) <- "numeric"  # convert from character to number

            fr <- xts(ohlc, dates, src="yahooj", updated=Sys.time())
            colnames(fr) <- paste(symname, cols, sep='.')

            fr <- convert.time.series(fr=fr,return.class=return.class)
            if(is.xts(fr))
                tclass(fr) <- index.class

            Symbols[[i]] <- symname
            if(auto.assign)
                assign(Symbols[[i]],fr,env)
            if(i >= 5 && length(Symbols) > 5) {
                message("pausing 1 second between requests for more than 5 symbols")
                Sys.sleep(1)
            }

            }, silent = TRUE)
            if (inherits(test, "try-error")) {
                msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                              ".\n", attr(test, "condition")$message)
                if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
                  stop(msg)
                }
                if (isTRUE(warnings)) {
                  warning(msg, call. = FALSE, immediate. = TRUE)
                }
                noDataSym <- c(noDataSym, returnSym[[i]])
            }
        }
        if(auto.assign)
            return(setdiff(returnSym, noDataSym))
        return(fr)
    }
# }}}

# getSymbols.google {{{
"getSymbols.google" <-
function(Symbols,env,return.class='xts',
         from='2007-01-01',
         to=Sys.Date(),
         ...)
{
  msg <- paste0(sQuote("getSymbols.google"), " is defunct.",
         "\nGoogle Finance stopped providing data in March, 2018.",
         "\nYou could try setting src = \"yahoo\" instead.",
         "\nSee help(\"Defunct\") and help(\"quantmod-defunct\")")
  .Defunct("getSymbols", "quantmod", msg = msg)
}
# }}}

# getSymbols.SQLite {{{
"getSymbols.SQLite" <- function(Symbols,env,return.class='xts',
                               db.fields=c('row_names','Open','High',
                                           'Low','Close','Volume','Adjusted'),
                               field.names = NULL,
                               dbname=NULL,
                               POSIX = TRUE,
                               ...) {
     importDefaults("getSymbols.SQLite")
     this.env <- environment()
     for(var in names(list(...))) {
        # import all named elements that are NON formals
        assign(var, list(...)[[var]], this.env)
     }
     if(!hasArg("verbose")) verbose <- FALSE
     if(!hasArg("auto.assign")) auto.assign <- TRUE
     if(!hasArg("warnings")) warnings <- TRUE

     if(!requireNamespace("DBI", quietly=TRUE))
       stop("package:",dQuote("DBI"),"cannot be loaded.")
     if(!requireNamespace("RSQLite", quietly=TRUE))
       stop("package:",dQuote("RSQLite"),"cannot be loaded.")

        drv <- DBI::dbDriver("SQLite")
        con <- DBI::dbConnect(drv,dbname=dbname)
        db.Symbols <- DBI::dbListTables(con)
        if(length(Symbols) != sum(Symbols %in% db.Symbols)) {
          missing.db.symbol <- Symbols[!Symbols %in% db.Symbols]
                warning(paste('could not load symbol(s): ',paste(missing.db.symbol,collapse=', ')))
                Symbols <- Symbols[Symbols %in% db.Symbols]
        }
        returnSym <- Symbols
        noDataSym <- NULL
        for(i in seq_along(Symbols)) {
            test <- try({
            if(verbose) {
                cat(paste('Loading ',Symbols[[i]],
                    paste(rep('.',10-nchar(Symbols[[i]])),collapse=''),
                    sep=''))
            }
            query <- paste("SELECT ",
                           paste(db.fields,collapse=','),
                           " FROM ",Symbols[[i]],
                           " ORDER BY row_names")
            rs <- DBI::dbSendQuery(con, query)
            fr <- DBI::fetch(rs, n=-1)
            #fr <- data.frame(fr[,-1],row.names=fr[,1])
            if(POSIX) {
              d <- as.numeric(fr[,1])
              class(d) <- c("POSIXt","POSIXct")
              fr <- xts(fr[,-1],order.by=d)
            } else {
              fr <- xts(fr[,-1],order.by=as.Date(as.numeric(fr[,1]),origin='1970-01-01'))
            }
            colnames(fr) <- paste(Symbols[[i]],
                                  c('Open','High','Low','Close','Volume','Adjusted'),
                                  sep='.')
            fr <- convert.time.series(fr=fr,return.class=return.class)
            if(auto.assign)
              assign(Symbols[[i]],fr,env)
            if(verbose) cat('done\n')
            }, silent = TRUE)
            if (inherits(test, "try-error")) {
                msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                              ".\n", attr(test, "condition")$message)
                if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
                  stop(msg)
                }
                if (isTRUE(warnings)) {
                  warning(msg, call. = FALSE, immediate. = TRUE)
                }
            }
        }
        DBI::dbDisconnect(con)
        if(auto.assign)
          return(setdiff(returnSym, noDataSym))
        return(fr)
}
"getSymbols.sqlite" <- getSymbols.SQLite
# }}}

# getSymbols.MySQL {{{
"getSymbols.MySQL" <- function(Symbols,env,return.class='xts',
                               db.fields=c('date','o','h','l','c','v','a'),
                               field.names = NULL,
                               user=NULL,password=NULL,dbname=NULL,host='localhost',port=3306,
                               ...) {
     importDefaults("getSymbols.MySQL")
     this.env <- environment()
     for(var in names(list(...))) {
        # import all named elements that are NON formals
        assign(var, list(...)[[var]], this.env)
     }
     if(!hasArg("verbose")) verbose <- FALSE
     if(!hasArg("auto.assign")) auto.assign <- TRUE
     if(!hasArg("warnings")) warnings <- TRUE

     if(!requireNamespace("DBI", quietly=TRUE))
       stop("package:",dQuote("DBI"),"cannot be loaded.")
     if(!requireNamespace("RMySQL", quietly=TRUE))
       stop("package:",dQuote("RMySQL"),"cannot be loaded.")

        if(is.null(user) || is.null(password) || is.null(dbname)) {
          stop(paste(
              'At least one connection argument (',sQuote('user'),
              sQuote('password'),sQuote('dbname'),
              ") is not set"))
        }
        con <- DBI::dbConnect(RMySQL::MySQL(),user=user,password=password,dbname=dbname,host=host,port=port)
        db.Symbols <- DBI::dbListTables(con)
        if(length(Symbols) != sum(Symbols %in% db.Symbols)) {
          missing.db.symbol <- Symbols[!Symbols %in% db.Symbols]
                warning(paste('could not load symbol(s): ',paste(missing.db.symbol,collapse=', ')))
                Symbols <- Symbols[Symbols %in% db.Symbols]
        }
        returnSym <- Symbols
        noDataSym <- NULL
        for(i in seq_along(Symbols)) {
            test <- try({
            if(verbose) {
                cat(paste('Loading ',Symbols[[i]],paste(rep('.',10-nchar(Symbols[[i]])),collapse=''),sep=''))
            }
            query <- paste("SELECT ",paste(db.fields,collapse=',')," FROM ",Symbols[[i]]," ORDER BY date")
            rs <- DBI::dbSendQuery(con, query)
            fr <- DBI::fetch(rs, n=-1)
            #fr <- data.frame(fr[,-1],row.names=fr[,1])
            fr <- xts(as.matrix(fr[,-1]),
                      order.by=as.Date(fr[,1],origin='1970-01-01'),
                      src=dbname,updated=Sys.time())
            colnames(fr) <- paste(Symbols[[i]],
                                  c('Open','High','Low','Close','Volume','Adjusted'),
                                  sep='.')
            fr <- convert.time.series(fr=fr,return.class=return.class)
            if(auto.assign)
              assign(Symbols[[i]],fr,env)
            if(verbose) cat('done\n')
            }, silent = TRUE)
            if (inherits(test, "try-error")) {
              msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                            ".\n", attr(test, "condition")$message)
              if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
                stop(msg)
              }
              if (isTRUE(warnings)) {
                warning(msg, call. = FALSE, immediate. = TRUE)
              }
              noDataSym <- c(noDataSym, returnSym[[i]])
            }
        }
        DBI::dbDisconnect(con)
        if(auto.assign)
          return(setdiff(returnSym, noDataSym))
        return(fr)
}
"getSymbols.mysql" <- getSymbols.MySQL
# }}}

# getSymbols.FRED {{{
`getSymbols.FRED` <- function(Symbols,env,
     return.class="xts", ...) {
     importDefaults("getSymbols.FRED")
     this.env <- environment()
     for(var in names(list(...))) {
        # import all named elements that are NON formals
        assign(var, list(...)[[var]], this.env)
     }
     if(!hasArg("verbose")) verbose <- FALSE
     if(!hasArg("auto.assign")) auto.assign <- TRUE
     if(!hasArg("warnings")) warnings <- TRUE
     if(!hasArg("from")) from <- ""
     if(!hasArg("to")) to <- ""

     FRED.URL <- "https://fred.stlouisfed.org/series"

     returnSym <- Symbols
     noDataSym <- NULL

     for(i in seq_along(Symbols)) {
       if(verbose) cat("downloading ",Symbols[[i]],".....\n\n")
       test <- try({
       URL <- paste(FRED.URL, "/", Symbols[[i]], "/downloaddata/", Symbols[[i]], ".csv", sep="")
       fr <- read.csv(curl::curl(URL),na.strings=".")

       if(verbose) cat("done.\n")
       fr <- xts(as.matrix(fr[,-1]),
                 as.Date(fr[,1],origin='1970-01-01'),
                 src='FRED',updated=Sys.time())
       dim(fr) <- c(NROW(fr),1)
       colnames(fr) <- as.character(toupper(Symbols[[i]]))
       # subset between from/to dates before we convert from xts
       fr <- fr[paste(from, to, sep = "/")]

       fr <- convert.time.series(fr=fr,return.class=return.class)
       Symbols[[i]] <-toupper(gsub('\\^','',Symbols[[i]]))
       if(auto.assign)
         assign(Symbols[[i]],fr,env)
       }, silent = TRUE)
       if (inherits(test, "try-error")) {
         msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                       ".\n", attr(test, "condition")$message)
         if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
           stop(msg)
         }
         if (isTRUE(warnings)) {
           warning(msg, call. = FALSE, immediate. = TRUE)
         }
         noDataSym <- c(noDataSym, returnSym[[i]])
       }
     }
     if(auto.assign)
       return(setdiff(returnSym, noDataSym))
     return(fr)
} #}}}

"getSymbols.cache" <- function() {}

# getFX {{{
`getFX` <-
function(Currencies,from=Sys.Date()-179,to=Sys.Date(),
         env=parent.frame(),
         verbose=FALSE,warning=TRUE,
         auto.assign=TRUE,...) {
  importDefaults("getFX")
  if(missing(env))
    env <- parent.frame(1)
  if(is.null(env))
    auto.assign <- FALSE
  if(!auto.assign && length(Currencies) > 1)
    stop("must use auto.assign=TRUE for multiple currency requests")
  #src <- c('oanda','FRED')[pmatch(src,c('oanda','FRED'))[1]]
  # parse Symbols
  # make symbols conform to service naming conventions
  # e.g. USD/JPY for oanda
  #
  #      DEXUSJP for FRED
  #
  #if(src[1]=="oanda") {
  getSymbols.oanda(Symbols=Currencies,from=from,to=to,
                   env=env,verbose=verbose,warning=warning,
                   auto.assign=auto.assign,...)
  #} else {
  #  getSymbols.FRED(Symbols=Currencies,env=env,verbose=verbose,warning=warning,...)
  #}
}
#}}}

# getMetals {{{
`getMetals` <-
function(Metals,from=Sys.Date()-179,to=Sys.Date(),
         base.currency="USD",env=parent.frame(),
         verbose=FALSE,warning=TRUE,
         auto.assign=TRUE,...) {
  importDefaults("getMetals")
  if(missing(env))
    env <- parent.frame(1)
  if(is.null(env))
    auto.assign <- FALSE
  metals <- c("XAU-GOLD","XPD-PALLADIUM","XPT-PLATINUM","XAG-SILVER")
  metals <- metals[sapply(Metals, function(x) grep(x,metals,ignore.case=TRUE))]
  metals <- as.character(sapply(metals,
                   function(x) {
                     paste(strsplit(x,'-')[[1]][1],base.currency,sep="/")
                   }))
  getSymbols.oanda(Symbols=metals,from=from,to=to,auto.assign=auto.assign,
                   env=env,verbose=verbose,warning=warning,...)
}
#}}}

# getRates {{{
`getRates` <-
function() {

}
#}}}

# getSymbols.csv {{{
"getSymbols.csv" <-
function(Symbols,env,
         dir="",
         return.class="xts",
         extension="csv",
         col.names=c('Open','High','Low','Close','Volume','Adjusted'),
         ...) {
  importDefaults("getSymbols.csv")
  this.env <- environment()
  for(var in names(list(...))) {
    assign(var,list(...)[[var]], this.env)
  }

  default.return.class <- return.class
  default.dir <- dir
  default.extension <- extension

  if(!hasArg("verbose")) verbose <- FALSE
  if(!hasArg("auto.assign")) auto.assign <- TRUE
  if(!hasArg("warnings")) warnings <- TRUE

  returnSym <- Symbols
  noDataSym <- NULL

  for(i in seq_along(Symbols)) {
    test <- try({
    return.class <- getSymbolLookup()[[Symbols[[i]]]]$return.class
    return.class <- ifelse(is.null(return.class),default.return.class,
                           return.class)
    dir <- getSymbolLookup()[[Symbols[[i]]]]$dir
    dir <- ifelse(is.null(dir),default.dir,
                           dir)
    extension <- getSymbolLookup()[[Symbols[[i]]]]$extension
    extension <- ifelse(is.null(extension),default.extension,
                           extension)

    if(verbose) cat("loading ",Symbols[[i]],".....")
    if(dir=="") {
      sym.file <- paste(Symbols[[i]],extension,sep=".")
    } else {
      sym.file <- file.path(dir,paste(Symbols[[i]],extension,sep="."))
    }
    if(!file.exists(sym.file)) {
      cat("\nfile ",paste(Symbols[[i]],"csv",sep='.')," does not exist ",
          "in ",dir,"....skipping\n")
      next
    }
    fr <- read.csv(sym.file)
    if(verbose)
      cat("done.\n")

    # ensure date column is character before calling as.Date
    asDateArgs <- list(x=as.character(fr[,1]))
    # use format passed via '...', if specified
    if(hasArg("format"))
      asDateArgs$format <- format
    # allow format from setSymbolLookup to override
    if(!is.null(getSymbolLookup()[[Symbols[[i]]]]$format))
      asDateArgs$format <- getSymbolLookup()[[Symbols[[i]]]]$format

    fr <- xts(fr[,-1],do.call("as.Date", asDateArgs),src='csv',updated=Sys.time())
    colnames(fr) <- paste(toupper(gsub('\\^','',Symbols[[i]])),col.names,sep='.')
    fr <- convert.time.series(fr=fr,return.class=return.class)
    Symbols[[i]] <-toupper(gsub('\\^','',Symbols[[i]]))
    if(auto.assign)
      assign(Symbols[[i]],fr,env)
    }, silent = TRUE)
    if (inherits(test, "try-error")) {
       msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                     ".\n", attr(test, "condition")$message)
       if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
         stop(msg)
       }
       if (isTRUE(warnings)) {
         warning(msg, call. = FALSE, immediate. = TRUE)
       }
      noDataSym <- c(noDataSym, returnSym[[i]])
    }
    }
    if(auto.assign)
      return(setdiff(returnSym, noDataSym))
    return(fr)
}
#}}}

# getSymbols.rds {{{
"getSymbols.rds" <-
function(Symbols,env,
         dir="",
         return.class="xts",
         extension="rds",
         col.names=c('Open','High','Low','Close','Volume','Adjusted'),
         ...) {
  importDefaults("getSymbols.rds")
  this.env <- environment()
  for(var in names(list(...))) {
    assign(var,list(...)[[var]], this.env)
  }

  default.return.class <- return.class
  default.dir <- dir
  default.extension <- extension

  if(!hasArg("verbose")) verbose <- FALSE
  if(!hasArg("auto.assign")) auto.assign <- TRUE
  if(!hasArg("warnings")) warnings <- TRUE

  returnSym <- Symbols
  noDataSym <- NULL

  for(i in seq_along(Symbols)) {
    test <- try({
    return.class <- getSymbolLookup()[[Symbols[[i]]]]$return.class
    return.class <- ifelse(is.null(return.class),default.return.class,
                           return.class)
    dir <- getSymbolLookup()[[Symbols[[i]]]]$dir
    dir <- ifelse(is.null(dir),default.dir,
                           dir)
    extension <- getSymbolLookup()[[Symbols[[i]]]]$extension
    extension <- ifelse(is.null(extension),default.extension,
                           extension)
    if(verbose) cat("loading ",Symbols[[i]],".....")
    if(dir=="") {
      sym.file <- paste(Symbols[[i]],extension,sep=".")
    } else {
      sym.file <- file.path(dir,paste(Symbols[[i]],extension,sep="."))
    }
    if(!file.exists(sym.file)) {
      cat("\nfile ",paste(Symbols[[i]],extension,sep='.')," does not exist ",
          "in ",dir,"....skipping\n")
      next
    }
    #fr <- read.csv(sym.file)
    fr <- readRDS(sym.file)
    if(verbose)
      cat("done.\n")
    if(!is.xts(fr)) fr <- xts(fr[,-1],as.Date(fr[,1],origin='1970-01-01'),src='rda',updated=Sys.time())
    colnames(fr) <- paste(toupper(gsub('\\^','',Symbols[[i]])),col.names,sep='.')
    fr <- convert.time.series(fr=fr,return.class=return.class)
    Symbols[[i]] <-toupper(gsub('\\^','',Symbols[[i]]))
    if(auto.assign)
      assign(Symbols[[i]],fr,env)
    }, silent = TRUE)
    if (inherits(test, "try-error")) {
      msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                    ".\n", attr(test, "condition")$message)
      if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
        stop(msg)
      }
      if (isTRUE(warnings)) {
        warning(msg, call. = FALSE, immediate. = TRUE)
      }
      noDataSym <- c(noDataSym, returnSym[[i]])
    }
    }
    if(auto.assign)
      return(setdiff(returnSym, noDataSym))
    return(fr)
}
#}}}

# getSymbols.rda {{{
"getSymbols.rda" <-
function(Symbols,env,
         dir="",
         return.class="xts",
         extension="rda",
         col.names=c('Open','High','Low','Close','Volume','Adjusted'),
         ...) {
  importDefaults("getSymbols.rda")
  this.env <- environment()
  for(var in names(list(...))) {
    assign(var,list(...)[[var]], this.env)
  }

  default.return.class <- return.class
  default.dir <- dir
  default.extension <- extension

  if(!hasArg("verbose")) verbose <- FALSE
  if(!hasArg("auto.assign")) auto.assign <- TRUE
  if(!hasArg("warnings")) warnings <- TRUE

  returnSym <- Symbols
  noDataSym <- NULL

  for(i in seq_along(Symbols)) {
    test <- try({
    return.class <- getSymbolLookup()[[Symbols[[i]]]]$return.class
    return.class <- ifelse(is.null(return.class),default.return.class,
                           return.class)
    dir <- getSymbolLookup()[[Symbols[[i]]]]$dir
    dir <- ifelse(is.null(dir),default.dir,
                           dir)
    extension <- getSymbolLookup()[[Symbols[[i]]]]$extension
    extension <- ifelse(is.null(extension),default.extension,
                           extension)
    if(verbose) cat("loading ",Symbols[[i]],".....")
    if(dir=="") {
      sym.file <- paste(Symbols[[i]],extension,sep=".")
    } else {
      sym.file <- file.path(dir,paste(Symbols[[i]],extension,sep="."))
    }
    if(!file.exists(sym.file)) {
      cat("\nfile ",paste(Symbols[[i]],extension,sep='.')," does not exist ",
          "in ",dir,"....skipping\n")
      next
    }
    #fr <- read.csv(sym.file)
    local.name <- load(sym.file)
    assign('fr',get(local.name))
    if(verbose)
      cat("done.\n")
    if(!is.xts(fr)) fr <- xts(fr[,-1],as.Date(fr[,1],origin='1970-01-01'),src='rda',updated=Sys.time())
    colnames(fr) <- paste(toupper(gsub('\\^','',Symbols[[i]])),col.names,sep='.')
    fr <- convert.time.series(fr=fr,return.class=return.class)
    Symbols[[i]] <-toupper(gsub('\\^','',Symbols[[i]]))
    if(auto.assign)
      assign(Symbols[[i]],fr,env)
    }, silent = TRUE)
    if (inherits(test, "try-error")) {
      msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                    ".\n", attr(test, "condition")$message)
      if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
        stop(msg)
      }
      if (isTRUE(warnings)) {
        warning(msg, call. = FALSE, immediate. = TRUE)
      }
      noDataSym <- c(noDataSym, returnSym[[i]])
    }
    }
    if(auto.assign)
      return(setdiff(returnSym, noDataSym))
    return(fr)
}
#}}}

# getSymbols.RData {{{
`getSymbols.RData` <- getSymbols.rda
# }}}

# getSymbols.IBrokers {{{
"getSymbols.IBrokers" <- function(Symbols, env, return.class='xts',
endDateTime, barSize='1 day', duration='1 M',
useRTH = '1', whatToShow = 'TRADES', time.format = '1', ...)
{
  importDefaults('getSymbols.IBrokers')
  this.env <- environment()
  for(var in names(list(...))) {
    assign(var, list(...)[[var]], this.env)
  }
  if(!hasArg("verbose")) verbose <- FALSE
  if(!hasArg("auto.assign")) auto.assign <- TRUE
  if(!hasArg("warnings")) warnings <- TRUE

  if(is.method.available("twsConnect","IBrokers")) {
    tws <- do.call('twsConnect',list(clientId=1001))
    on.exit(do.call('twsDisconnect',list(tws)))

    if(missing(endDateTime)) endDateTime <- NULL

    returnSym <- Symbols
    noDataSym <- NULL

    for(i in seq_along(Symbols)) {
      test <- try({
      Contract <- getSymbolLookup()[[Symbols[i]]]$Contract
      if(inherits(Contract,'twsContract')) {
        fr <- do.call('reqHistoricalData',list(tws, Contract, endDateTime=endDateTime,
                                barSize=barSize, duration=duration,
                                useRTH=useRTH, whatToShow=whatToShow,
                                timeFormat=time.format, verbose=verbose))
        fr <- convert.time.series(fr=fr, return.class=return.class)
        if(auto.assign)
          assign(Symbols[[i]], fr, env)
        if(i < length(Symbols)) {
          if(verbose) cat('waiting for TWS to accept next request')
          for(pacing in 1:6) {
            if(verbose) cat('.',sep='')
            Sys.sleep(1)
          }
          if(verbose) cat('done\n')
        }
      } else if (isTRUE(warnings)) {
        warning(paste('unable to load',Symbols[i],': missing twsContract definition'))
      }
    }, silent = TRUE)
    if (inherits(test, "try-error")) {
      msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                    ".\n", attr(test, "condition")$message)
      if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
        stop(msg)
      }
      if (isTRUE(warnings)) {
        warning(msg, call. = FALSE, immediate. = TRUE)
      }
      noDataSym <- c(noDataSym, returnSym[[i]])
    }
    }
    if(auto.assign)
      return(setdiff(returnSym, noDataSym))
    return(fr)
  }
}
# }}}

# getSymbols.RBloomberg {{{
"getSymbols.RBloomberg" <- function() {}
# }}}

# getSymbols.url {{{
"getSymbols.url" <- function() {}
# }}}

# getSymbols.freelunch {{{
"getSymbols.freelunch" <- function() {}
# }}}

# getSymbols.RODBC {{{
"getSymbols.RODBC" <- function() {}
# }}}

# getSymbols.RSQLite {{{
"getSymbols.RSQLite" <- function() {}
# }}}

# getSymbols.ROracle {{{
"getSymbols.ROracle" <- function() {}
# }}}

# getSymbols.oanda {{{
`getSymbols.oanda` <-
function(Symbols,env,return.class='xts',
         from=Sys.Date()-179,
         to=Sys.Date(),
         ...) {

     importDefaults("getSymbols.oanda")
     this.env <- environment()
     for(var in names(list(...))) {
        # import all named elements that are NON formals
        assign(var, list(...)[[var]], this.env)
     }

     if(!auto.assign && length(Symbols) > 1)
       stop("must use auto.assign=TRUE for multiple Symbols requests")
     default.return.class <- return.class
     default.from <- from
     default.to <- to

     if(!hasArg("verbose")) verbose <- FALSE
     if(!hasArg("auto.assign")) auto.assign <- TRUE
     if(!hasArg("warnings")) warnings <- TRUE

     returnSym <- Symbols
     noDataSym <- NULL

     for(i in seq_along(Symbols)) {
       test <- try({
       return.class <- getSymbolLookup()[[Symbols[[i]]]]$return.class
       return.class <- ifelse(is.null(return.class),default.return.class,
                              return.class)
       from <- getSymbolLookup()[[Symbols[[i]]]]$from
       from <- ifelse(is.null(from),default.from,from)
       from <- as.Date(from, origin='1970-01-01')
       to <- getSymbolLookup()[[Symbols[[i]]]]$to
       to <- ifelse(is.null(to),default.to,to)
       to <- as.Date(to, origin='1970-01-01')

       Symbols.name <- getSymbolLookup()[[Symbols[[i]]]]$name
       Symbols.name <- ifelse(is.null(Symbols.name),Symbols[[i]],Symbols.name)
       currency.pair <- strsplit(toupper(Symbols.name),"/")[[1]]
       if(length(currency.pair) != 2) {

         if(isTRUE(warnings)) {
           warning(paste("incorrectly specified currency pair",Symbols.name))
         }
         next
       }

       if(verbose) cat("downloading ",Symbols.name,".....")
       # throw warning, but return as much data as possible
       if(from < Sys.Date() - 180) {
         if(isTRUE(warnings)) {
           warning("Oanda only provides historical data for the past 180 days.",
                   " Symbol: ", Symbols[[i]])
         }
       }
       oanda.URL <- paste0("https://fxds-hcc.oanda.com/api/data/update",
                           "?&source=OANDA&adjustment=0",
                           "&base_currency=", currency.pair[1],
                           "&start_date=", from,
                           "&end_date=", to,
                           "&period=daily",
                           "&price=mid",
                           "&view=table",
                           "&quote_currency_0=", currency.pair[2])
       # Fetch data (jsonlite::fromJSON will handle connection)
       tbl <- jsonlite::fromJSON(oanda.URL, simplifyVector = FALSE)
       Data <- tbl[[1]][[1]]$data

       # timestamps are ms since midnight 1970-01-01
       secs <- as.numeric(sapply(Data, `[[`, 1L)) / 1000
       dates <- as.Date(.POSIXct(secs, tz = "UTC"))

       # remove thousands separator and convert to numeric
       rates <- sapply(Data, `[[`, 2L)
       if(is.character(rates))
         rates <- as.numeric(gsub(",", "", rates))

       if(verbose) cat("done.\n")
       fr <- xts(rates, dates, src="oanda", updated=Sys.time())
       fr <- fr[paste(from, to, sep="/")]  # subset to requested timespan
       colnames(fr) <- gsub("/",".",Symbols[[i]])
       fr <- convert.time.series(fr=fr,return.class=return.class)
       Symbols[[i]] <-toupper(gsub('\\^|/','',Symbols[[i]]))
       if(auto.assign)
         assign(Symbols[[i]],fr,env)
     }, silent = TRUE)
     if (inherits(test, "try-error")) {
       msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                     ".\n", attr(test, "condition")$message)
       if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
         stop(msg)
       }
       if (isTRUE(warnings)) {
         warning(msg, call. = FALSE, immediate. = TRUE)
       }
       noDataSym <- c(noDataSym, returnSym[[i]])
     }
     }
     if(auto.assign)
       return(setdiff(returnSym, noDataSym))
     return(fr)
}#}}}

#
#  Download OHLC Data From Alpha Vantage
#
#  Meant to be called internally by getSymbols().
#
getSymbols.av <- function(Symbols, env, api.key,
                          return.class="xts",
                          periodicity="daily",
                          adjusted=FALSE,
                          interval="1min",
                          output.size="compact",
                          data.type="json",
                          ...)
{
  importDefaults("getSymbols.av")
  this.env <- environment()
  for (var in names(list(...))) {
    assign(var, list(...)[[var]], this.env)
  }

  if (!hasArg("api.key")) {
    stop("getSymbols.av: An API key is required (api.key). Free registration",
         " at https://www.alphavantage.co/.", call.=FALSE)
  }
  if (!hasArg("auto.assign")) auto.assign <- TRUE
  if (!hasArg("verbose")) verbose <- FALSE
  if (!hasArg("warnings")) warnings <- TRUE

  valid.periodicity <- c("daily", "weekly", "monthly", "intraday")
  periodicity <- match.arg(periodicity, valid.periodicity)
  interval <- match.arg(interval, c("1min", "5min", "15min", "30min", "60min"))
  output.size <- match.arg(output.size, c("compact", "full"))

  default.return.class <- return.class
  default.periodicity <- periodicity

  #
  # For daily, weekly, and monthly data, timestamps are "yyyy-mm-dd".
  # For intraday data, timestamps are "yyyy-mm-dd HH:MM:SS".
  #
  convertTimestamps <- function(ts, periodicity, tz) {
    if (periodicity == "intraday")
      as.POSIXct(ts, tz=tz)
    else
      as.Date(ts)
  }

  downloadOne <- function(sym, default.return.class, default.periodicity) {

    return.class <- getSymbolLookup()[[sym]]$return.class
    return.class <- if (is.null(return.class)) default.return.class else return.class

    periodicity <- getSymbolLookup()[[sym]]$periodicity
    periodicity <- if (is.null(periodicity)) default.periodicity else periodicity
    periodicity <- match.arg(periodicity, valid.periodicity)

    if (adjusted && periodicity == "intraday")
      stop("getSymbols.av: Intraday data cannot be adjusted.", call.=FALSE)

    sym.name <- getSymbolLookup()[[sym]]$name
    sym.name <- if (is.null(sym.name)) sym else sym.name

    FUNCTION <- paste0("TIME_SERIES_",
      switch(periodicity,
             daily = if (adjusted) "DAILY_ADJUSTED" else "DAILY",
             weekly = if (adjusted) "WEEKLY_ADJUSTED" else "WEEKLY",
             monthly = if (adjusted) "MONTHLY_ADJUSTED" else "MONTHLY",
             intraday = "INTRADAY" ))

    if (verbose) cat("loading", sym.name, ".....")

    URL <- paste0("https://www.alphavantage.co/query",
                  "?function=", FUNCTION,
                  "&symbol=", sym.name,
                  "&interval=", interval,
                  "&outputsize=", output.size,
                  "&datatype=", data.type,
                  "&apikey=", api.key)

    if (data.type == "json") {
      lst <- jsonlite::fromJSON(URL)

      #
      # Errors return a list with one element: An error message
      #
      if (length(lst) == 1)
        stop("getSymbols.av: ", lst[[1]], call.=FALSE)

      if (verbose) cat("done.\n")

      #
      # The first element of 'lst' is the metadata.
      # Typical metadata (in JSON format):
      #
      #   "Meta Data": {
      #     "1. Information": "Intraday (1min) prices and volumes",
      #     "2. Symbol": "MSFT",
      #     "3. Last Refreshed": "2017-05-23 16:00:00",
      #     "4. Interval": "1min",
      #     "5. Output Size": "Compact",
      #     "6. Time Zone": "US/Eastern"
      #   }
      #
      meta <- lst[[1]]
      tz <- meta[["6. Time Zone"]]
      updated <- convertTimestamps(meta[["3. Last Refreshed"]], periodicity, tz=tz)

      #
      # The second element of 'lst' is the data: a list.
      # The names of the list elements are the timestamps.
      # Typical list element, non-adjusted data (in JSON format):
      #
      #   "2017-05-23": {
      #     "1. open": "68.6750",
      #     "2. high": "68.7100",
      #     "3. low": "68.6400",
      #     "4. close": "68.6800",
      #     "5. volume": "1591941"
      #   }
      #
      # Typical list element, adjusted data (again, JSON format):
      #
      #  "2017-06-30": {
      #    "1. open": "68.7800",
      #    "2. high": "69.3800",
      #    "3. low": "68.7400",
      #    "4. close": "68.9300",
      #    "5. adjusted close": "68.9300",
      #    "6. volume": "23039328",
      #    "7. dividend amount": "0.00",
      #    "8. split coefficient": "1.0000"
      #   },
      #
      elems <- lst[[2]]
      tm.stamps <- convertTimestamps(names(elems), periodicity, tz=tz)

      if (adjusted) {
        av_names <- c("1. open", "2. high", "3. low", "4. close", "6. volume", "5. adjusted close")
        qm_names <- paste(sym, c("Open", "High", "Low", "Close", "Volume", "Adjusted"), sep=".")
      } else {
        av_names <- c("1. open", "2. high", "3. low", "4. close", "5. volume")
        qm_names <- paste(sym, c("Open", "High", "Low", "Close", "Volume"), sep=".")
      }

      # extract columns from each element (row) and unlist to a vector
      rows <- lapply(elems, function(x) unlist(x[av_names], use.names=FALSE))
      rows <- do.call(rbind, rows)
      colnames(rows) <- qm_names
      storage.mode(rows) <- "numeric"
      # convert matrix to xts
      mat <- xts(rows, tm.stamps, src="alphavantage", updated=updated)
      mat <- convert.time.series(mat, return.class=return.class)
    } else {
      mat <- as.xts(read.zoo(curl::curl(URL), header=TRUE, sep=","),
                    src="alphavantage", updated=Sys.time())
      # convert column names to symbol.series
      cn <- colnames(mat)
      cn <- paste0(toupper(substring(cn, 1, 1)), substring(cn, 2))
      colnames(mat) <- paste(sym, cn, sep=".")

      mat <- convert.time.series(mat, return.class=return.class)
    }
    if (auto.assign)
      assign(sym, mat, env)
    return(mat)
  }

  returnSym <- Symbols
  noDataSym <- NULL
  matrices <- list()

  for(i in seq_along(Symbols)) {
    test <- try({
      matrices[[i]] <- downloadOne(Symbols[[i]],
        default.return.class = default.return.class,
        default.periodicity = default.periodicity)
    }, silent = TRUE)
    if (inherits(test, "try-error")) {
      msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                    ".\n", attr(test, "condition")$message)
      if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
        stop(msg)
      }
      if (isTRUE(warnings)) {
        warning(msg, call. = FALSE, immediate. = TRUE)
      }
      noDataSym <- c(noDataSym, returnSym[[i]])
    }
  }

  if (auto.assign) {
    return(setdiff(returnSym, noDataSym))
  } else {
    return(matrices[[1]])
  }
}

# Mnemonic alias, letting callers use getSymbols("IBM", src="alphavantage")
getSymbols.alphavantage <- getSymbols.av

#
#  Download OHLC Data From Tiingo
#
#  Meant to be called internally by getSymbols().
#
getSymbols.tiingo <- function(Symbols, env, api.key,
                              return.class="xts",
                              periodicity="daily",
                              adjust=FALSE,
                              from='2007-01-01',
                              to=Sys.Date(),
                              ...) {

  importDefaults("getSymbols.tiingo")
  this.env <- environment()
  for (var in names(list(...))) {
    assign(var, list(...)[[var]], this.env)
  }

  if (!hasArg("api.key")) {
    stop("getSymbols.tiingo: An API key is required (api.key). Register",
         " at https://api.tiingo.com.", call.=FALSE)
  }
  if (!hasArg("auto.assign")) auto.assign <- TRUE
  if (!hasArg("verbose")) verbose <- FALSE
  if (!hasArg("warnings")) warnings <- TRUE

  valid.periodicity <- c("daily", "weekly", "monthly", "annually")
  periodicity <- match.arg(periodicity, valid.periodicity)
  default.return.class <- return.class
  default.periodicity <- periodicity

  downloadOne <- function(sym, default.return.class, default.periodicity) {

    return.class <- getSymbolLookup()[[sym]]$return.class
    return.class <- if (is.null(return.class)) default.return.class else return.class
    periodicity <- getSymbolLookup()[[sym]]$periodicity
    periodicity <- if (is.null(periodicity)) default.periodicity else periodicity
    periodicity <- match.arg(periodicity, valid.periodicity)
    sym.name <- getSymbolLookup()[[sym]]$name
    sym.name <- if (is.null(sym.name)) sym else sym.name

    if (verbose) cat("loading", sym.name, ".....")
    from.strftime <- strftime(from, format = "%Y-%m-%d")
    to.strftime <- strftime(to, format = "%Y-%m-%d")

    URL <- paste0("https://api.tiingo.com/tiingo/daily/",
                  sym.name, "/prices",
                  "?startDate=", from.strftime,
                  "&endDate=", to.strftime,
                  "&resampleFreq=", periodicity,
                  "&format=csv",
                  "&token=", api.key)
    #tiingo will return a text error for ticker not found, which read.csv converts
    #to a zero row, 1 column data.frame, with a warning
    stock.data <- suppressWarnings(read.csv(URL, as.is=TRUE))
    # check for error
    if (NCOL(stock.data) == 1) {
      msg <- sub("Error: ", "", colnames(stock.data))
      stop(msg, call. = FALSE)
    }

    tm.stamps <- as.Date(stock.data[, "date"])

    if (adjust) {
      stock.data <- stock.data[, c("adjOpen", "adjHigh", "adjLow", "adjClose", "adjVolume")]
      colnames(stock.data) <- paste(sym, c("Open", "High", "Low", "Close", "Volume"), sep=".")
    } else {
      stock.data <- stock.data[, c("open", "high", "low", "close", "volume", "adjClose")]
      colnames(stock.data) <- paste(sym, c("Open", "High", "Low", "Close", "Volume", "Adjusted"), sep=".")
    }

    # convert data to xts
    xts.data <- xts(stock.data, tm.stamps, src="tiingo", updated=Sys.time())
    xts.data <- convert.time.series(xts.data, return.class=return.class)
    if (auto.assign)
      assign(sym, xts.data, env)
    return(xts.data)
  }

  returnSym <- Symbols
  noDataSym <- NULL
  matrices <- list()

  for(i in seq_along(Symbols)) {
    test <- try({
      matrices[[i]] <- downloadOne(Symbols[[i]],
        default.return.class = default.return.class,
        default.periodicity = default.periodicity)
    }, silent = TRUE)
    if (inherits(test, "try-error")) {
      msg <- paste0("Unable to import ", dQuote(returnSym[[i]]),
                    ".\n", attr(test, "condition")$message)
      if (hasArg(".has1sym.") && match.call(expand.dots=TRUE)$.has1sym.) {
        stop(msg)
      }
      if (isTRUE(warnings)) {
        warning(msg, call. = FALSE, immediate. = TRUE)
      }
      noDataSym <- c(noDataSym, returnSym[[i]])
    }
  }

  if (auto.assign) {
    return(setdiff(returnSym, noDataSym))
  } else {
    return(matrices[[1]])
  }
}

# convert.time.series {{{
`convert.time.series` <- function(fr,return.class) {
       if('quantmod.OHLC' %in% return.class) {
         class(fr) <- c('quantmod.OHLC','zoo')
         return(fr)
       } else
       if('xts' %in% return.class) {
         return(fr)
       }
       if('zoo' %in% return.class) {
         return(as.zoo(fr))
       } else
       if('ts' %in% return.class) {
         fr <- as.ts(fr)
         return(fr)
       } else
       if('data.frame' %in% return.class) {
         fr <- as.data.frame(fr)
         return(fr)
       } else
       if('matrix' %in% return.class) {
         fr <- as.data.frame(fr)
         return(fr)
       } else
       if('timeSeries' %in% return.class) {
         if(requireNamespace("timeSeries", quietly=TRUE)) {
           fr <- timeSeries::timeSeries(coredata(fr), charvec=as.character(index(fr)))
           return(fr)
         } else {
           warning(paste("'timeSeries' from package 'timeSeries' could not be loaded:",
                   " 'xts' class returned"))
         }
       }
}#}}}

# removeSymbols {{{
"removeSymbols" <-
function(Symbols=NULL,env=parent.frame()) {
    if(exists('.getSymbols',env,inherits=FALSE)) {
    getSymbols <- get('.getSymbols',env,inherits=FALSE)
      if(is.null(Symbols)) {
        #Symbols <- paste(getSymbols)
        Symbols <- names(getSymbols)
      } else {
        #Symbols now has ONLY existing Symbols in it
        #Symbols <- Symbols[Symbols %in% unlist(getSymbols)]
        Symbols <- Symbols[Symbols %in% names(getSymbols)]
      }
      remove(list=as.character(Symbols),envir=env)
      Symbols.remaining <- getSymbols[!names(getSymbols) %in% Symbols]
      if(length(Symbols.remaining) == 0) {
        remove(list=c('.getSymbols'),envir=env)
      } else {
        assign('.getSymbols',Symbols.remaining,env)
      }
    }
}
# }}}

# showSymbols {{{
"showSymbols" <-
function(env=parent.frame()) {
    if(exists('.getSymbols',env,inherits=FALSE)) {
        return(unlist(get('.getSymbols',env)))
    } else { return(NULL) }
}
# }}}

# saveSymbols {{{
"saveSymbols"<-
function(Symbols=NULL,file.path=stop("must specify 'file.path'"),env=parent.frame()) {
  if(exists('.getSymbols',env,inherits=FALSE)) {
    getSymbols <- get('.getSymbols',env,inherits=FALSE)
      if(is.null(Symbols)) {
        Symbols <- names(getSymbols)
      } else {
        #Symbols now has ONLY existing Symbols in it
        Symbols <- Symbols[Symbols %in% names(getSymbols)]
      }
    for(each.symbol in Symbols) {
      save(list=each.symbol,
           file=paste(file.path,'/',each.symbol,".RData",sep=''),
           envir=env)
    }
  }
}
# }}}

# buildData {{{
"buildData" <- function(formula,na.rm=TRUE,return.class="zoo") {
  if(is.quantmod(formula)) {
    fr <- modelData(formula)
  } else {
    fr <- modelData(specifyModel(formula,na.rm=na.rm))
  }
  fr <- convert.time.series(fr=fr,return.class=return.class)
}
#}}}