shinypod 0.0.99

As you write more-and-more shiny apps and they become more-and-more complex, you may notice a couple of things:

1. Among different apps, you may be doing the same things over and over again, like uploading and parsing csv files.
2. Within a given app, your ui and server functions may become difficult to manage as inputs, outputs, and reactives pile up.

Adressing these problems is the motivation for shiny to introduce modules.

The goals of this package are to propose a design framework for shiny modules, and provide some implementations.

So far, we have reusable modules for:

• uploading and parsing a CSV file into a data-frame (including handling time-zones)
• configuring a two-y-axes dygraph using a data-frame

Installation

This package is not on CRAN; however, it is based on the new CRAN (0.13.0) version of shiny. To install:

devtools::install_github("ijlyttle/shinypod")

Philosophy

For each module foo, we have fundamental functions: foo_ui_input(), foo_ui_output(), possibly foo_ui_misc(), and foo_server(). The fundamental UI functions each return a named shiny::tagList; the server function is called by shiny::callModule.

For each module foo, we also have a couple of functions that return ui arrangements for a sidebar layout: foo_ui_sidebar_side() and foo_ui_sidebar_main(). These functions rely on the fundamental UI functions.

Each of these functions has an associated arguement id, which is used to keep orderly the shiny namespace.

Examples

Let's say you wanted to be able to upload and parse a csv file, and have the dataframe be returned by a reactive function.

We can write this app using the "all-in-one" approach:

library("shiny")
library("shinyjs")
library("shinyBS")
library("shinypod")

app <- shinyApp(
  ui = {
    shinyUI(
      fluidPage(
        useShinyjs(),
        sidebarLayout(
          sidebarPanel(read_delim_sidebar_side("read_csv")),
          mainPanel(read_delim_sidebar_main("read_csv"))
        )
      )
    )  
  },
  server = {
    shinyServer(function(input, output, session) {
    
      rct_data <- callModule(read_delim_server, id = "read_csv")
    
      observe(print(rct_data()))
    })  
  }
)

runApp(app)

Deployed examples

Some simple shinypod apps deployed at shinyapps:

• Parse CSV file
• Parse CSV file and dygraph