---
title: "Project Profiles"
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{Project Profiles}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---

```{r, include = FALSE}
knitr::opts_chunk$set(
  eval = FALSE,
  collapse = TRUE,
  comment = "#>"
)
```


## Introduction

Starting with `renv 0.13.0`, it is possible to activate and switch between
different profiles associated with a project. A profile can be thought of as
a different mode in which a project is used. For example:

- A "development" profile might be used when developing and testing a project,
- A "production" profile might be used for production deployments,
- A "shiny" profile might be used when running the Shiny application.

At its heart, activating or using a particular profile implies using a different
set of paths for the project library and lockfile. With this, it is possible
to associate different packages, and different dependencies, with different
workflows in a single project using `renv`.


## Usage

By default, `renv` projects use the "default" profile, which implies that
library and lockfile paths are set in the typical way. To activate a particular
profile, use:

```
renv::activate(profile = "dev")
```

This creates a profile called `"dev"`, and sets it as the default for the
project, so that newly-launched R sessions will operate using the `"dev"`
profile. After setting this and re-launching R, you should see that the
default library and lockfile paths are resolved within the `renv/profiles/dev`
folder from the project root.

Alternatively, if you want to activate a particular profile for an R session
without setting it as the default for new R sessions, you can use:

```
Sys.setenv(RENV_PROFILE = "dev")
```

and `renv` will automatically use that profile as appropriate when computing
library and lockfile paths. Similarly, from the command line, you might
enforce the use of a particular profile in an `renv` project with:

```
export RENV_PROFILE=dev
```

With that set, `renv` would default to using the `"dev"` profile for any
newly-launched R sessions within `renv` projects.

To activate the "default" profile used by a project, use:

```
renv::activate(profile = NULL)
```


## Managing Profile-specific Dependencies

Profile-specific package dependencies can be declared within the project's
top-level `DESCRIPTION` file. For example, to declare that the `shiny`
profile depends on the [shiny] and [tidyverse] packages:

```
Config/renv/profiles/shiny/dependencies: shiny, tidyverse
```

If you'd like to also declare that these packages should be installed from
a custom remote (analogous to the `Remotes` field for the default profile),
you can define those remotes with a separate field:

```
Config/renv/profiles/shiny/remotes: rstudio/shiny, tidyverse/tidyverse
```

These remotes will then be respected in calls to `renv::install()`.

The packages and remotes must be specified separately, as `renv` cannot
determine the package name associated with a particular remote without
explicitly resolving that remote. Remote resolution normally requires a web
request, which `renv` tries to avoid in "regular" dependency discovery.

If you'd prefer that only the packages enumerated in this field are used, you
can opt-in to using `"explicit"` snapshots, and leave the `Imports`, `Depends`
and `Suggests` fields blank:

```{r}
renv::settings$snapshot.type("explicit")
```

When set, only the dependencies listed in the project `DESCRIPTION` file will
be used when the lockfile is generated. See `?renv::snapshot` for more details.



[shiny]: https://shiny.rstudio.com/
[tidyverse]: https://www.tidyverse.org/
