Running redis-based workers in R on Heroku

enqueue.r

# same code used in https://gist.github.com/pedro/f931e8cd20b5770b6780
# only using doRedis instead of doParallel
library(foreach)
library(doRedis)

redis_url <- Sys.getenv("REDIS_URL")
host <- gsub("redis://.*@(.+):.*", "\\1", redis_url)
pass <- gsub("redis://.*:(.+)@.*", "\\1", redis_url)
port <- as.integer(gsub(".*:(.*)$", "\\1", redis_url))
registerDoRedis("jobs", host=host, port=port, password=pass)

x <- iris[which(iris[,5] != "setosa"), c(1,5)]
trials <- 10000
ptime <- system.time({
	r <- foreach(icount(trials), .combine=cbind) %dopar% {
		 ind <- sample(100, 100, replace=TRUE)
		result1 <- glm(x[ind,2]~x[ind,1], family=binomial(logit))
		coefficients(result1)
	}
})[3]
print(ptime)

init.r

# used by the R buildpack to install dependencies:
# https://github.com/virtualstaticvoid/heroku-buildpack-r
install.packages("foreach", dependencies = TRUE)
install.packages("rredis", dependencies = TRUE)
install.packages("doRedis", dependencies = TRUE)

output.txt

$ heroku run Rscript enqueue.r

# in another window:
$ heroku logs --tail
Processing job  3  from queue  jobs 
Processing task 225 ... from queue jobs jobID 3 
Processing job  3  from queue  jobs 
Processing task 1325 ... from queue jobs jobID 3 
Processing job  3  from queue  jobs 
Processing task 7810 ... from queue jobs jobID 3 
Processing job  3  from queue  jobs 
Processing task 2226 ... from queue jobs jobID 3 
Processing job  3  from queue  jobs 
Processing task 5289 ... from queue jobs jobID 3 
Processing job  3  from queue  jobs 
Processing task 1963 ... from queue jobs jobID 3 
Processing job  3  from queue  jobs 
Processing task 7053 ... from queue jobs jobID 3 
...

worker.r

library(doRedis)
redis_url <- Sys.getenv("REDIS_URL")
host <- gsub("redis://.*@(.+):.*", "\\1", redis_url)
pass <- gsub("redis://.*:(.+)@.*", "\\1", redis_url)
port <- as.integer(gsub(".*:(.*)$", "\\1", redis_url))
redisWorker("jobs", host=host, port=port, password=pass)