Creating a R Shiny App to display Sankey taking input on Nodes and Links from users

Question

I am trying to create a R Shiny App that takes input from users on the Links and Nodes as .csv files and generates a Sankey based on that input. The input files are uploading and displaying as expected but the Sankey is not generating.

If I run the code generically, without Shiny, the Sankey is generating without any issues from my source csv files.

library(shiny)
library(DT)
library(readxl)
library(highcharter)
library(dplyr)
library(data.table)
library(networkD3)

ui = fluidPage(
  titlePanel("Sankey"),
  fileInput("link", "Select links file"
  ),
  fileInput("node", "Select nodes file"
  ),
  DT::dataTableOutput("VLout"),
  DT::dataTableOutput("VNout"),
  sankeyNetworkOutput("plot")
)
server <- function(input, output) {
  links <- reactive({
    if (is.null(input$link)) {
      return("")
    }
    # actually read the file
    data.frame(Source = read.csv(input$link$datapath)$Source,
               Target = read.csv(input$link$datapath)$Target,
               Value = read.csv(input$link$datapath)$Value)
  })
  nodes <- reactive({
    if (is.null(input$node)) {
      return("")
    }
    # actually read the file
    data.frame(Name = read.csv(input$node$datapath)$Name)
  })
    output$VLout <- DT::renderDataTable({
      links()
    })
    output$VNout <- DT::renderDataTable({
      nodes()
    }) 
  output$plot <- {
    renderSankeyNetwork({
    sankeyNetwork(Links=links(), Nodes=nodes(), Source="Source", Target="Target", 
                  Value = "Value", NodeID = "Name", sinksRight = FALSE, 
                  fontSize = 16, nodeWidth = 45, nodePadding = 15, 
                  margin = list(left = 175, top = 100, right = 175, bottom = 100))           
})
  }
}
shinyApp(ui = ui, server = server)

score 0 · Answer 1 · answered Feb 12 '23 at 00:14

(Without data I can't test this. Just a hunch as links() is a reactive.

output$plot <- {
    renderSankeyNetwork({
    sankeyNetwork(Links=links(), Nodes=nodes(), Source=links()$Source, Target=links()$Target, 
                  Value = links()$Value, NodeID = links()$Name, sinksRight = FALSE, 
                  fontSize = 16, nodeWidth = 45, nodePadding = 15, 
                  margin = list(left = 175, top = 100, right = 175, bottom = 100))           
})

Creating a R Shiny App to display Sankey taking input on Nodes and Links from users

1 Answers1