library(shiny)
library(jsonlite)
library(reshape2)
options(shiny.maxRequestSize=30*1024^2)
shinyServer(

  function(input, output){
     src <- renderText({paste0(readLines(input$file1),collapse = ',')})
     x <- renderText({jsonlite::fromJSON(src,flatten = TRUE)})
     output$contents <- renderTable({as.data.frame(x)})
  }
)