Hosting a Single App with Shiny Server

If you’ve written a Shiny app and have reached a point where you would like to share it with others … you have a few options:

Given that you have hardware (or a cloud setup) to install a server, Shiny Server Open Source may be a good solution.

I’ve deployed dozens of apps on different Shiny servers. In some cases, I may need a single server that hosts an entire directory of apps. With this configuration (the default for Shiny Server Open Source) each app is available at {url}/{app-name}.

However, I occasionally want a server to host a single application that will be available at {url}. In this case, I just need to adjust a few parameters in server configuration. Below is an example shiny-server.conf file for an app called “prod” that lives in /srv/shiny-server/prod on the host machine:

# Define the user we should use when spawning R Shiny processes
run_as shiny;

# disable idle timeout to retain connection
app_idle_timeout 0;

# Define a top-level server which will listen on a port
server {
  # Instruct this server to listen on port 80. The app at dokku-alt need expose PORT 80, or 500 e etc. See the docs
  listen 80;

  # Define the location available at the base URL
  location / {

    # Run this location in 'site_dir' mode, which hosts the entire directory
    # tree at '/srv/shiny-server'
    app_dir /srv/shiny-server/prod;
    # Define where we should put the log files for this location
    log_dir /var/log/shiny-server;
    # Should we list the contents of a (non-Shiny-App) directory when the user 
    # visits the corresponding URL?
    directory_index on;

Note that the parameters of interest for this post are:

  • listen … explicitly tell the server to listen 80 so that apps are served at port 80 … otherwise you’ll need to specify the port number after the url (i.e. {url}:3737)
  • location … we don’t want to pass any special location to the base URL since we’re defining an app_dir (see below) … so location / should work fine
  • app_dir … rather than serving up an entire directory of apps, we just have one … make sure the app_dir specifies the directory where the app is on the host machine (usually /srv/shiny-server/{app-name})