docker-machine-aws-furrr.R

library(furrr)

# localhost -> AWS EC2 linux -> Docker running on that -> R

# dm_create() and dm_ip() are from an unreleased R pkg I whipped up, dockermachinery
# https://github.com/DavisVaughan/dockermachinery

# Creates 1 t2.micro EC2 instance
dm_create("amazonec2", "dockertest")

# Get the ip
ip <- dm_ip("dockertest")

# Sadly, it shoves the pem file here, and we don't have any option to use our own.
# (technically there is a way, but it's broken according to the internet)
ssh_private_key_file <- "/Users/davisvaughan/.docker/machine/machines/dockertest/id_rsa"

# This is the rscript command necessary to run a future command
# It downloads rocker/r-base and starts up a fresh container each time
# net host is necessary to be able to connect back up to my localhost. 
rscript <- c("sudo", "docker", "run", "--net=host", "rocker/r-base", "Rscript")

# Connect!
cl <- makeClusterPSOCK(
  
  ## Public IP number of EC2 instance
  ip,
  
  ## User name (always 'ubuntu')
  user = "ubuntu",
  
  ## Use private SSH key registered with AWS
  rshopts = c(
    "-o", "StrictHostKeyChecking=no",
    "-o", "IdentitiesOnly=yes",
    "-i", ssh_private_key_file
  ),
  
  rscript = rscript,
  
  ## Set up .libPaths() for the 'ubuntu' user and
  ## install future/purrr/furrr packages
  rscript_args = c(
    "-e", shQuote("local({p <- Sys.getenv('R_LIBS_USER'); dir.create(p, recursive = TRUE, showWarnings = FALSE); .libPaths(p)})"),
    "-e", shQuote("if (!requireNamespace('furrr', quietly = TRUE)) install.packages('furrr')")
  ),
  
  dryrun = FALSE
)

plan(cluster, workers = cl)
future_map(1:5, ~.x)