basic data setup for sample covid chart

basicDataSetup.R

library(leaflet)
library(rgdal)
library(RColorBrewer)

#load spatial data
world_spdf <- readOGR( 
  dsn = getwd() , 
  layer = "TM_WORLD_BORDERS_SIMPL-0.3",
  verbose = FALSE
)

#load covid data set
covidData <- read.csv("https://covid19.who.int/WHO-COVID-19-global-data.csv", fileEncoding="UTF-8-BOM", stringsAsFactors = FALSE)
covidData <- na.omit(covidData)

#select a certain date
selectedData <- covidData[covidData$Date_reported == "2020-07-15", ]

#match cases and spatial data via ISO2/Country Code
world_spdf$Cases <- selectedData$Cumulative_cases[match(world_spdf$ISO2, selectedData$Country_code)]

#create label texts
world_spdf@data$LabelText <- paste0(
  "<b>Country:</b> ", world_spdf@data$NAME,"<br>", 
  "<b>Cases:</b> ", format(world_spdf@data$Cases, nsmall=0, big.mark=","))

#define colorpalette for chart legend
paletteBins <- c(0, 50000, 100000, 250000, 500000, 1000000, 2500000, 5000000, 10000000)
colorPalette <- colorBin(palette = "YlOrBr", domain = covidData$Cumulative_cases, na.color = "transparent", bins = paletteBins)