convert examples to use curl package

[dmenne]

windows 10, problem with RCurls and TLS

URL <- "https://raw.githubusercontent.com/christophergandrud/d3Network/sankey/JSONdata/energy.json"
Energy <- RCurl::getURL(URL, ssl.verifypeer = TRUE)

>Error in function (type, msg, asError = TRUE)  : 
  error:1407742E:SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version

RCurl::curlVersion()$ssl_version
>> [1] "OpenSSL/1.0.0o"

[cjyetman]

This is not the repo for RCurl, so if you want that error specifically to be addressed, you'll probably have to report it to the developers of that package.

In order to get examples here working that use RCurl to get the data, you could instead use the more modern pkg curl. For example...

library(curl)
library(jsonlite)
library(networkD3)

URL <- "https://raw.githubusercontent.com/christophergandrud/d3Network/sankey/JSONdata/energy.json"
energy <- fromJSON(curl(URL))

EngLinks <- energy$links
EngNodes <- energy$nodes

sankeyNetwork(Links = EngLinks, Nodes = EngNodes, Source = "source",
              Target = "target", Value = "value", NodeID = "name",
              fontSize = 12, nodeWidth = 30)

[dmenne]

Yes, I know this is not the curl repo, and I got it to work anyway. Just a report for easy correction in your markdown example