How to dockerise a Shiny app

How to port a shiny app into a container

Prerequisites

In order to build a container with your shiny app inside you need three files:

1. app.R containing your working shiny app
2. Dockerfile
3. Rprofile.site

Starting from your working directory proj, teh file hierarchy must be:

-- proj 
   -- Dockerfile
   -- Rprofile.site
   -- iris
      -- app.R

app.R

Your app.R contains your shiny app. As a first example you may consider the iris example from https://shiny.rstudio.com/gallery/kmeans-example.html. The iris example is also available here. Store app.R inside the application directory say iris.

Dockerfile

Your docker file contains the following instructions:

# where to download the base R docker image from
FROM rocker/r-base

# system libraries commonly required by R packages
RUN apt-get update && apt-get install -y \
    sudo \
    pandoc \
    pandoc-citeproc \
    libcurl4-gnutls-dev \
    libcairo2-dev \
    libxt-dev \
    libssl-dev \
    libssh2-1-dev


# Install required packages
RUN R -e "install.packages(c('shiny', 'rmarkdown'), repos='https://cloud.r-project.org/')"


# copy the app to the image
RUN mkdir /root/iris
COPY iris /root/iris


COPY Rprofile.site /usr/lib/R/etc/

EXPOSE 3333

CMD ["R", "-e", "shiny::runApp('/root/iris')"]

Rprofile.site

The Rprofile.site file states that:

local({
   options(shiny.port = 3333, shiny.host = "0.0.0.0")
})

Build the container

Build docker image with

sudo docker build   --tag iris .

Test by

Assuming that everything worked out correctly, if you issue:

sudo docker run -it --rm -p 3333:3333 iris 

you should see the iris application at 0.0.0.0:3333