e_config
In golem: A Framework for Robust Shiny Applications

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
library(golem)
x <- file.path(
  tempdir(),
  "golex"
)
unlink(x, TRUE, TRUE)

x <- golem::create_golem(x, package_name = "golex", open = FALSE)
old <- setwd(x)
knitr::opts_knit$set(root.dir = x)

library(golem)

old <- setwd(x)

About `inst/golem-config.yml`

When you start a new {golem} application, you'll find a file called golem-config.yml in the inst/ folder.

By default, this file contains the name of your app, its version, and the default working directory (which is the root of your package).

This config file is based on the {config} format, which allows you to create configuration files for different application contexts. Please refer to this package documentation for more information.

Setting `golem-config`

Here is what the default config file looks like:

default:
  golem_name: golex
  golem_version: 0.0.0.9000
  app_prod: no

production:
  app_prod: yes

dev:
  golem_wd: !expr golem::pkg_path()

default/golem_name, default/golem_version, default/app_prod are usable across the whole life of your golem app: while developing, and also when in production.
production/app_prod might be used for adding elements that are to be used once the app is in production.
dev/golem_wd is in a dev config because the only moment you might reliably use this config is while developing your app. Use the app_sys() function if you want to rely on the package path once the app is deployed.

The good news is that if you don't want/need to use {config}, you can safely ignore this file, just leave it where it is: it is used internally by the {golem} functions.

These options are globally set with:

set_golem_options()

cat(
  sep = "\n",
  readLines(
    "inst/golem-config.yml"
  )
)

The functions reading the options in this config file are:

get_golem_name()
get_golem_wd()
get_golem_version()

You can set these with:

set_golem_name("this")
set_golem_wd(".")
set_golem_version("0.0.1")

cat(
  sep = "\n",
  readLines(
    "inst/golem-config.yml"
  )
)

Using `golem-config`

If you're already familiar with the {config} package, you can use this file just as any config file.

{golem} comes with an amend_golem_config() function to add elements to it.

amend_golem_config(
  key = "where",
  value = "indev"
)
amend_golem_config(
  key = "where",
  value = "inprod",
  config = "production"
)

Will result in a golem-config.yml file as such:

cat(
  sep = "\n",
  readLines(
    file.path(x, "inst/golem-config.yml")
  )
)

`app_config.R`

In R/app_config.R, you'll find a get_golem_config() function that allows you to retrieve config from this config file:

pkgload::load_all()
get_golem_config(
  "where"
)
get_golem_config(
  "where",
  config = "production"
)

Or using the env var (default {config} behavior):

Sys.setenv("R_CONFIG_ACTIVE" = "production")
get_golem_config("where")

`golem_config` vs `golem_options`

There is two ways to configure golem apps:

The golem_opts in the run_app() function
The golem-config.yml file

The big difference between these two is that the golem options from run_app() are meant to be configured during runtime: you'll be doing run_app(val = "this"), whereas the golem-config is meant to be used in the back-end, and will not be linked to the parameters passed to run_app() (even if this is technically possible, this is not the main objective),.

It's also linked to the R_CONFIG_ACTIVE environment variable, just as any {config} file.

The idea is also that the golem-config.yml file is shareable across {golem} projects (golem_opts are application specific), and will be tracked by version control systems.

Note for `{golem}` < 0.2.0 users

If you've built an app with {golem} before the version 0.2.0, this config file doesn't exist: you'll be prompted to create it if you update a newer version of {golem}.