Fix TZ showing in Shiny tables

fixTZinShinyTables.R

# Fix TZ showing in tables : drawdown Shiny example
# micstr 4 July 2017 
# shiny 0.12. broke the perfapp drawdown  tables now showing dates with Timezone e.g.
#   2016-04-30T00:00:00Z

#"POSIXt objects are now serialized to JSON in UTC8601 format (like
#"2015-03-20T20:00:00Z"), instead of as seconds from the epoch. If you
#have a Shiny app which uses sendCustomMessage() to send datetime
#(POSIXt) objects, then you may need to modify your Javascript code to
#receive time data in this format."


library(PerformanceAnalytics)
library(shiny)
library(DT) # is order right?

# get frag of data 
returns <- structure(c(NA, 0.002, 0.0001, -0.0026, 0.03, -0.008), class = c("xts", "zoo"),
                     .indexCLASS = c("POSIXct", "POSIXt"), 
                     tclass = c("POSIXct","POSIXt"),
                     .indexTZ = "UTC", tzone = "UTC",
                     index = structure(c(1414800000, 
                                         1417305600, 
                                         1419984000, 
                                         1422662400, 
                                         1425081600, 1427760000),
                                       tzone = "UTC",
                                       tclass = c("POSIXct","POSIXt")),
                     .Dim = c(6L, 1L), .Dimnames = list(NULL, "nav"))

server <- function(input, output) {

output$drawdownTable <-  DT::renderDataTable({
    
    out <- table.Drawdowns(returns)
    # This is how you fix TZ
    out$From   <- as.Date(out$From)
    out$To     <- as.Date(out$To)
    out$Trough <- as.Date(out$Trough)
    
    out}, options = k.dt.opt
  )
}


ui <- fluidPage(
  sidebarLayout(
    sidebarPanel(
      sliderInput("obs", "ignore me:", min = 6, max = 20, value = 12)
    ),
    mainPanel(DT::dataTableOutput("drawdownTable"))
  )
)


shinyApp(ui = ui, server = server)