appifyr

Create Web Applications from R Functions (Updated May 4, 2025)

Turn your R functions into interactive web applications with minimal code!

appifyr bridges the gap between R's analytical capabilities and web interfaces by:

1. Taking regular R functions
2. Automatically generating HTML forms for function parameters
3. Connecting these inputs to OpenCPU API calls
4. Displaying the function outputs (currently plots)

Quick Start

# Install the package
install.packages("remotes")
remotes::install_github("retowyss/appifyr")

# Create a simple function
histogram_app <- function(n, bins) {
  hist(rnorm(n), breaks = bins, main = "Random Normal Distribution")
}

# Create a web interface for your function
library(appifyr)
app <- appify(
  f = "histogram_app", 
  inps = list(
    n = inp_number(from = 10, to = 1000, label = "Sample Size"),
    bins = inp_number(from = 5, to = 30, label = "Number of Bins")
  )
)

# To run the app, you'll need OpenCPU
# install.packages("opencpu")
# opencpu::ocpu_start_app("YourPackageName")

How It Works

appifyr uses OpenCPU as a backend to create web interfaces for R functions. Unlike Shiny, which requires learning Shiny-specific syntax, appifyr works with regular R functions and requires minimal JavaScript/HTML knowledge.

Differences from Shiny

• Shiny: You start with the goal of creating a specific app and write R code to achieve that goal.
• appifyr: You start with existing R code and create an app to visualize your function.

Documentation and Examples

• Appifyr Documentation
• Demo App - Sepals and Petals

Running Apps

To run apps created with appifyr, you need OpenCPU:

# Install OpenCPU
install.packages("opencpu")

# Clone the demo application
# git clone https://github.com/retowyss/sepals-and-petals.git

# Build and start the app
appifyr::build_app()
opencpu::ocpu_start_app("SepalsAndPetals")

Key Features

• Simple API: The main function appify() takes an R function and specifications for inputs
• Intuitive Input Creation: Helper functions like inp_text(), inp_number(), and inp_dropdown()
• Built-in Web Components: Generates Bootstrap-styled form elements and layout
• Integration with OpenCPU: Uses the OpenCPU JavaScript library to handle API calls

Requirements

• R ≥ 4.1.0
• OpenCPU for running the apps