r-data-science / apptemplate1

Template repo containing a shiny app built as an R package. Repo includes workflows for automated package and app (via shinytest2) unit testing, as well as the docker image deployment of the app in this package.

apptemplate1

Shiny App via R Package

This is a working demo of (and template for) a single shiny app fully wrapped into an R package that is complete with unit testing, code coverage, and end-to-end shiny app testing with shinytest2.

Single-App R Package Benefits

• All latest functions, ui/server code, and dependencies for a single app are accessible after installing or updating a single R package
• All functionality of the app, including simulated user-interactions, as well as load-testing, can be included in the unit and coverage tests executed by a standard R package check
• Workflow for automated CI/Deployment of app is simplified to that of a standard R package. App can be deployed as a docker image as part of workflow that checks, tests, and builds the package

Additional Resources

• To unit tests this shiny app, including simulated user actions and snapshots, I utilize the package shinytest2 in conjuction with snapshot expectations from package testthat
• For additional information on how to load test shiny apps, both locally as well as a deployed app, see shinyloadtest for more info

For an example of a multi-app R package, see here (LINK).

Package Structure

R/
├──app-run.R........................App server/ui code + function to launch app 
├──app-plots.R......................App functionality to build and save plot/data 
└──app-utils.R......................All other functions needed during app session

tests/testthat/
├── test-app-run.R..................End-to-end app and user-interactions tests 
├── test-app-plots.R................Isolated unit testing of app plot functions
├── test-app-utils.R................Isolated unit testing of other app functions
├── _snaps..........................Snapshots are saved here in testing
└── _tools..........................Contains helpers for debugging
    ├── dl-artifacts.sh.............Download gh actions artifacts by id
    └── list-artifacts.sh...........List all gh actions artifacts for repo

inst/ 
├── docker..........................Docker context used in CI/Deploy Workflow
│   ├── Dockerfile..................Dockerfile to build image of deployed app 
│   └── Rprofile.site...............Copied to image on docker build
└── docs
    └── template.Rmd................Template Report used by app on user action

.github/workflows/
├── R-CMD-check.yaml................Test app via package build/check steps
└── test-coverage.yaml..............Test and report coverage of app codebase

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Install & Run App

In R Session

This package exports a single R function that launches the packaged shiny app:

# remotes::install_github("r-data-science/apptemplate1")
apptemplate1::templateApp()

In Docker Container

To run this as a docker container, perform the following bash commands:

sudo docker pull bfatemi/apptemplate1:latest
sudo docker run --name demo-app \
  -p 3939:3939 --rm -dt bfatemi/apptemplate1:latest

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Proprietary - Do Not Distribute