inst/test-app/server.R

In shrektan/test.shiny.app: Test App to Debug Shiny Server Docker Image

library(shiny)
pkgs <- c("rmarkdown", "tinytex")
if ( any(miss_pkgs <- !pkgs %in% installed.packages()) ) {
  stop("must install ", paste0(pkgs[miss_pkgs], collapse = ", "), " first.")
}

function(input, output, session) {
  output$word <- downloadHandler(
    filename = function() "sample.docx",
    content = function(filename) {
      cmd <- sprintf(
        '"rmarkdown::render(\'test-word.Rmd\', output_file = \'%s\')"',
        normalizePath(filename, winslash = "\\", mustWork = FALSE)
      )
      result <- system2("Rscript", args = c("-e", cmd), stdout = TRUE, stderr = TRUE)
      output$result <- renderPrint({
        cat(result, sep = "\n")
      })
    }
  )

  output$pdf <- downloadHandler(
    filename = function() "sample.pdf",
    content = function(filename) {
      cmd <- sprintf(
        '"rmarkdown::render(\'test-pdf.Rmd\', output_file = \'%s\')"',
        normalizePath(filename, winslash = "\\", mustWork = FALSE)
      )
      result <- system2("Rscript", args = c("-e", cmd), stdout = TRUE, stderr = TRUE)
      output$result <- renderPrint({
        cat(result, sep = "\n")
      })
    }
  )

  observeEvent(input$run, {
    file <- tempfile(fileext = ".R")
    writeLines(input$code, con = file)
    cmd <- sprintf(
      '"source(\'%s\', encoding = \'UTF-8\')"',
      normalizePath(file, winslash = "\\", mustWork = FALSE)
    )
    result <- system2("Rscript", args = c("-e", cmd), stdout = TRUE, stderr = TRUE)
    output$result2 <- renderPrint({
      cat(result, sep = "\n")
    })
  })
}