Understanding golem options (golem_config vs golem_options)

[kyleweise]

Hey @ColinFay and golem team,

I have a question I hope is pretty straightforward. Even after reading this, I'm still a bit confused on options as they pertain to golem shiny applications.

Basically, I have two databases, Development and Production. When I am testing/developing an app locally, I'd like to use the Development credentials, and similarly when the app is hosted on RSConnect, I'd like to use the Production credentials.

For Development, I store credentials in a .Renivron file, for Production I store credentials in RSConnect environment variables. In both cases, I use the !expr Sys.getenv("[option_name]") syntax in golem_config.yml to get the value.

I am curious as to how I would go about allowing my app to be run in both DEV and PROD modes, locally. Basically, allow me to "turn a switch" so that I can connect to Production to see what the app looks like before I actually deploy it to RSConnect. In my golem_utils_server.R file, I have the following:

if(golem::app_dev()){
  message("Connected to Development DB")
  #Dev pool connection
  pool <- pool::dbPool(
    RPostgres::Postgres(),
    dbname = get_golem_config("dev_db_name"),
    host = get_golem_config("dev_db_host"),
    port = get_golem_config("dev_db_port"),
    user = get_golem_config("dev_db_username"),
    password = get_golem_config("dev_db_password")
  )
} else if(golem::app_prod()){
  message("Connected to Production DB")
  #Prod pool connection
  pool <- pool::dbPool(
    RPostgres::Postgres(),
    dbname = get_golem_config("prod_db_name"),
    host = get_golem_config("prod_db_host"), 
    port = get_golem_config("prod_db_port"), 
    user = get_golem_config("prod_db_username"),
    password = get_golem_config("prod_db_password")
  )
}

onStop(function() {
  pool::poolClose(pool)
})

and the golem_config.yml looks like

default:
  golem_name: GeneDataEditoR
  golem_version: '0.1'
  app_prod: no
  dev_db_username: !expr Sys.getenv("db_username")
  dev_db_password: !expr Sys.getenv("db_pw")
  dev_db_port: !expr Sys.getenv("db_port")
  dev_db_host: !expr Sys.getenv("db_host")
  dev_db_name: !expr Sys.getenv("db_name")
production:
  app_prod: yes
dev:
  golem_wd: /home/kweise/GeneDataEditoR
rsconnect:
    prod_db_username: !expr Sys.getenv("db_username")
    prod_db_password: !expr Sys.getenv("db_pw")
    prod_db_port: !expr Sys.getenv("db_port")
    prod_db_host: !expr Sys.getenv("db_host")
    prod_db_name: !expr Sys.getenv("db_name")

I tried setting: options(golem.app.prod = T), but I'm still seeing "Connected to Development DB" when I run the app. How can I make golem::app_prod() return TRUE?

Thanks so much! And again, amazing package!

-Kyle

[ColinFay]

Hey @kyleweise,

Thanks for your question :)

golem_config relies on the GOLEM_CONFIG_ACTIVE to find its values.

So basically, given the following yaml:

default:
  db: defaultdb
production:
  db: abcd
dev:
  db: xyz

Here is how it works:

# No envvar, returning the default
> get_golem_config("db")
[1] "defaultdb"
# With "production" `GOLEM_CONFIG_ACTIVE`
> Sys.setenv("GOLEM_CONFIG_ACTIVE" = "production")
> get_golem_config("db")
[1] "abcd"
> Sys.setenv("GOLEM_CONFIG_ACTIVE" = "dev")
> get_golem_config("db")
[1] "xyz"

In your usecase, if you add GOLEM_CONFIG_ACTIVE = rsconnect as env var inside your RStudio Connect, that should do the trick :)

Let me know,
Colin

[kyleweise]

Hey @ColinFay, thanks for getting back to me! Not sure I was clear enough in my first post. I am currently able to use dev credentials while in development, and production credentials on RSConnect; that's not an issue. I want to be able to connect to Production (ie. use the rsconnect section of the config.yml), while developing.

For example, imagine two versions of the same database table, one on Development, one on Production. I've been developing some application, and over the course of this development I've made multiple insertions and deletions to the Development version, and am now at a good stopping point. I want to be able to test the application on the Production table, to ensure that it works/looks the same as how it does in Development. The only way I have now to do that is to commit/push my untested code, and then see how the app looks on RSConnect.

Maybe I'm overthinking this. But even when I tried: Sys.setenv("GOLEM_CONFIG_ACTIVE" = "rsconnect"), then re-ran the application, I'm still seeing the "Connected to Development DB" message.