EPI 590R - {renv}

What is `{renv}`?

{renv} is an R package for managing project dependencies and creating reproducible environments

Benefits of using `{renv}`

Isolation: Creates project-specific environments separate from the global R library.
Reproducibility: Ensures consistent package versions for code reproducibility.
Collaboration: Facilitates sharing and collaborating on projects with others.

Getting Started with `{renv}`

Install {renv}

install.packages("renv")

Initialize a project

renv::init()

Install packages

install.packages("other_package")
# only an option when using renv!
install.packages("github_user/github_package")

Track dependencies via a lockfile

renv::snapshot()

Behind the scenes

Your project .Rprofile is updated to include:

source("renv/activate.R")

This is run every time R starts, and does some management of the library paths to make sure when you call install.packges("package") or library(package) it does to the right place (renv/library/R-{version}/{computer-specifics})
A renv.lock file (really just a text file) is created to store the names and versions of the packages.

`renv.lock`

{
  "R": {
    "Version": "4.3.0",
    "Repositories": [
      {
        "Name": "CRAN",
        "URL": "https://cran.rstudio.com"
      }
    ]
  },
  "Packages": {
    "R6": {
      "Package": "R6",
      "Version": "2.5.1",
      "Source": "Repository",
      "Repository": "CRAN",
      "Requirements": [
        "R"
      ],
      "Hash": "470851b6d5d0ac559e9d01bb352b4021"
    },
    base64enc": {
      "Package": "base64enc",
      "Version": "0.1-3",
      "Source": "Repository",
      "Repository": "CRAN",
      "Requirements": [
        "R"
      ],
      "Hash": "543776ae6848fde2f48ff3816d0628bc"
    },

Using `{renv}` later

Restore an environment

renv::restore()

Install new packages

install.packages("other_package")

Update the lockfile

renv::snapshot()

Collaboration with `{renv}`

Share the project’s renv.lock file with collaborators to ensure consistent environments
When they run renv::restore(), the correct versions of the packages will be installed on their computer

renv::restore()

Other helpful functions

Remove packages that are no longer used:

renv::clean()

Check the status of the project library with respect to the lockfile:

renv::status()

This will tell you to renv::snapshot() to add packages you’ve installed but haven’t snapshotted, or renv::restore() if you’re missing packages you need but which aren’t installed

Conclusion

{renv} benefits:

Isolation, reproducibility, and collaboration

Getting started with {renv}

Initialize a project using renv::init()
Install packages and store with renv::snapshot()
Restore later or elsewhere with renv::restore()

Exercises

Install a new R package of your choice. (Not sure what to choose? Try one of these fun packages. For example, I did install.packages("hadley/emo").)
Create an R script and save it in your R project. Include some code that requires the package. For example:

emo::ji("banana")

Run renv::status() to make sure your project picked up the package as a dependency.
Run renv::snapshot() to record that package in your lockfile.
Open your lockfile and look for your new package. For example, mine now has:

"emo": {
      "Package": "emo",
      "Version": "0.0.0.9000",
      "Source": "git",
      "RemoteType": "git",
      "RemoteUrl": "https://github.com/hadley/emo",
      "RemoteHost": "api.github.com",
      "RemoteUsername": "hadley",
      "RemoteRepo": "emo",
      "RemoteRef": "master",
      "RemoteSha": "3f03b11491ce3d6fc5601e210927eff73bf8e350",
      "Requirements": [
        "R",
        "assertthat",
        "crayon",
        "glue",
        "lubridate",
        "magrittr",
        "purrr",
        "rlang",
        "stringr",
        "utils"
      ],
      "Hash": "eb32b8f0bb50621ad498f5d836b546a4"
    },