Database path in dev and production

[pythiantech]

For my {golem} based Shiny app, I am defining the path to my database in golem-config.yml file as this path is different in dev and production:

default:
  golem_name: TMSGolem
  golem_version: 0.0.0.9000
  app_prod: no
  dbpath: data/ctms.db
production:
  app_prod: yes
  dbpath: /home/data/ctms.db
dev:
  golem_wd: /Users/dhirajkhanna/Documents/shiny_experiments/TMSGolem

Thereafter I am defining a function in golem_utils_server.R :

#Pool Handler
pool <- pool::dbPool(
  drv = RSQLite::SQLite(),
  dbname = get_golem_config('dbpath') 
)

While this works, is it the right way to define the path?
Secondly, how do I switch over to config values for ‘production’?

In run_dev.R, I tried options(golem.app.prod = TRUE) but the dbpath picked up is still what is there in the default configuration.

I am also thinking perhaps making an entry like this in the Dockerfile would work?
CMD R -e "Sys.setenv('R_CONFIG_ACTIVE' = 'production')"
Haven't tested this as I don't have access to the production server yet.

And thanks again for making such a terrific package!

[ColinFay]

Hey @pythiantech,

Side note before answering: thanks for the positive feedback 🤘. That always means a lot to us.

Side note two: as of golem v0.3.1, you can use the GOLEM_CONFIG_ACTIVE env var if you really want to focus on using the golem-config file, without conflicting with potential {config} elements (notably on RStudio Connect).

1. Yes, this is the correct way to do, you can find an example of this behavior here :

• https://engineering-shiny.org/golem.html#manipulating-golem-config.yml

As you can see, the behavior is the following one:

# default 
get_golem_config(
  "MONGODBURL"
)
[1] "localhost"

# Changing the config ENV_VAR
Sys.setenv("GOLEM_CONFIG_ACTIVE" = "production")
get_golem_config(
  "MONGODBURL"
)
[1] "0.0.0.0"

A full example of a working app playing with GOLEM_CONFIG_ACTIVE can be found here https://github.com/ColinFay/golemexamples/tree/master/golemyamlapps

1.5 side note, you should define the Pool inside another function, so that the pool can be created at runtime, something like :

make_pool <- function(){
	pool::dbPool(
		drv = RSQLite::SQLite(),
		dbname = get_golem_config('dbpath') 
	)
}

Then in app_server :

app_serve <- function(){
	pool <- make_pool()
}

That way, the pool will be created at runtime not when compiling the package.
see #552 (comment) for a discussion around this.

2. Yes, that's a way to do it, by defining Sys.setenv('GOLEM_CONFIG_ACTIVE' = 'production'); just before the run_app(). You can also play with .Renviron files or the {dotenv} package, but to be honest for just one env_var, you can definitely do it with Sys.setenv.

Cheers,
Colin

[pythiantech]

Thanks @ColinFay for your answer and the additional side not on the make_pool() function. Much appreciated, merci beaucoup!

[pythiantech]

Hello @ColinFay, I finally got access to the production server and was hence able to test my Docker image. Unfortunately it fails as the production configuration is not set. As you suggested, this is what I did in my Dockerfile:

RUN mkdir /home/data
COPY data /home/data
RUN mkdir /build_zone
ADD . /build_zone
WORKDIR /build_zone
RUN R -e 'remotes::install_local(upgrade="never")'
RUN rm -rf /build_zone
EXPOSE 80
CMD R -e "options('shiny.port'=80,shiny.host='0.0.0.0');Sys.setenv('GOLEM_CONFIG_ACTIVE' = 'production');TMSGolem::run_app()"

However, with this, the default configuration gets picked up and not the production which is defined as follows in golem-config.yml:

default:
  golem_name: TMSGolem
  golem_version: 0.0.0.9000
  app_prod: no
  dbpath: data/ctms.db
  vectorpath: data/course_vectors/
  studentpics: data/student_pics2/
production:
  app_prod: yes
  dbpath: /home/data/ctms.db
  vectorpath: /home/data/course_vectors/
  studentpics: /home/data/student_pics2/
dev:
  golem_wd: /Users/dhirajkhanna/Documents/shiny_experiments/TMSGolem

The workaround that I am using currently (and I think is quite sloppy) is to have Sys.setenv('GOLEM_CONFIG_ACTIVE' = 'production') included in golem_utils_server.R. This works, but I have to change this every time I want to build a Docker image.

Can you please tell me what am I doing wrong here?

[emilyriederer]

I have a similar question. I've set the GOLEM_CONFIG_ACTIVE environment variable on my server, and it is accessible from my app. However, app_dev() still evaluations to TRUE. I am currently solving for this by manually editing the final line of my Dockerfile to set the golem.app.prod option:

CMD R -e "options('shiny.port'=$PORT,shiny.host='0.0.0.0',golem.app.prod = TRUE);charlie::run_app()"

It's simple enough to programmatically replace the last line of my Dockerfile but it feels hackish.

Commenting to follow for any other tips on how to convince a golem app to run in prod.