Simplify getSymbols.tiingo() implementation

Remove the data.type parameter because getSymbols.tiingo() always
converts to an xts object. This user is not affected by which protocol
is used and handling the JSON response adds complexity. Use the CSV
interface because Tiingo said it's slightly more efficient and it
simplifies our implementation.

Fixes #343.

.gitignore

@@ -5,3 +5,4 @@ quantmod.Rproj
 src/*.o
 src/*.so
 src/*.dll
+*.Rproj

R/getSymbols.R

@@ -1470,7 +1470,6 @@ getSymbols.tiingo <- function(Symbols, env, api.key,
                               adjust=FALSE,
                               from='2007-01-01',
                               to=Sys.Date(),
-                              data.type="json",
                               ...) {
 
   importDefaults("getSymbols.tiingo")
@@ -1510,62 +1509,30 @@ getSymbols.tiingo <- function(Symbols, env, api.key,
     if (verbose) cat("loading", sym.name, ".....")
     from.strftime <- strftime(from, format = "%Y-%m-%d")
     to.strftime <- strftime(to, format = "%Y-%m-%d")
-
-    tiingo.names <- c("open", "high", "low", "close", "volume",
-                      "adjOpen", "adjHigh", "adjLow", "adjClose",
-                      "adjVolume", "divCash", "splitFactor")
-    qm.names <- paste(sym, c("Open", "High", "Low", "Close", "Volume",
-                             "Open", "High", "Low", "Close", "Volume",
-                             "DivCash", "SplitFactor"), sep=".")
-    if (isTRUE(adjust)) {
-      return.columns <- tiingo.names[6:10]
-    } else {
-      return.columns <- tiingo.names[1:5]
-    }
+
     URL <- paste0("https://api.tiingo.com/tiingo/",
                   periodicity, "/",
                   sym.name, "/prices",
                   "?startDate=", from.strftime,
                   "&endDate=", to.strftime,
-                  "&format=", data.type,
-                  "&columns=", paste0(return.columns, collapse=","))
-    # If rate limit is hit, the csv API returns HTTP 200 (OK), while json API
-    # returns HTTP 429. The latter caused download.file() to error, but the
-    # contents of 'tmp' still contain the error message.
-    h <- curl::new_handle()
-    curl::handle_setheaders(h, Authorization = paste("Token", api.key))
-    response <- curl::curl_fetch_memory(URL, h)
-    response.data <- rawToChar(response$content)
-
-    if (data.type == "json") {
-      stock.data <- jsonlite::fromJSON(response.data)
-      if (verbose) cat("done.\n")
-    } else {
-      stock.data <- read.csv(text=response.data, as.is=TRUE)
-    }
+                  "&format=csv",
+                  "&token=", api.key)
+    #tiingo will return a text error for ticker not found, which read.csv converts
+    #to a zero row, 1 column data.frame, with a warning
+    stock.data <- suppressWarnings(read.csv(URL, as.is=TRUE))
     # check for error
-    if (!all(return.columns %in% names(stock.data))) {
-      if (data.type == "json") {
-        msg <- stock.data$detail
-      } else {
-        msg <- readLines(response.data, warn=FALSE)
-      }
-      msg <- sub("Error: ", "", msg)
+    if (NCOL(stock.data) == 1) {
+      msg <- sub("Error: ", "", colnames(stock.data))
       stop(msg, call. = FALSE)
     }
+
     tm.stamps <- as.POSIXct(stock.data[, "date"], ...)
-    stock.data[, "date"] <- NULL
-
-    # adjusted column names
-    adjcols <- grepl("^adj", colnames(stock.data))
-    # order Tiingo column names before converting to quantmod names
-    stock.data <- OHLCV(stock.data)
-    if (any(adjcols)) {
-      # put adjusted columns last
-      stock.data <- stock.data[, c(which(!adjcols), which(adjcols))]
+    if (adjust) {
+      stock.data <- stock.data[, c("adjOpen", "adjHigh", "adjLow", "adjClose", "adjVolume")]
+    } else {
+      stock.data <- stock.data[, c("open", "high", "low", "close", "volume")]
     }
-    # now convert to quantmod column names
-    colnames(stock.data) <- qm.names[match(colnames(stock.data), tiingo.names)]
+    colnames(stock.data) <- paste(sym, c("Open", "High", "Low", "Close", "Volume"), sep=".")
 
     # convert data to xts
     xts.data <- xts(stock.data, tm.stamps, src="tiingo", updated=Sys.time())