Heroku Buildpack R - plumber Example

.r-version

3.4.3

README.md

See virtualstaticvoid/heroku-buildpack-r#107

heroku create --stack heroku-16

heroku buildpacks:add https://github.com/virtualstaticvoid/heroku-buildpack-r.git#heroku-16

git push heroku master

heroku logs # to check

curl -v -L https://your-heroku-app-name.heroku.com/mean
curl -v -d "a=1" -d "b=2" -L https://your-heroku-app-name.herokuapp.com/sum

app.R

library(plumber)

port <- Sys.getenv('PORT')

r <- plumb("/app/myfile.R")

r$run(host='0.0.0.0', port=strtoi(port))

Aptfile

libxml2-dev

init.R

#
# Example R code to install packages
# See http://cran.r-project.org/doc/manuals/R-admin.html#Installing-packages for details
#

###########################################################
# Update this line with the R packages to install:

my_packages = c("plumber")

###########################################################

install_if_missing = function(p) {
  if (p %in% rownames(installed.packages()) == FALSE) {
    install.packages(p, dependencies = TRUE)
  }
  else {
    cat(paste("Skipping already installed package:", p, "\n"))
  }
}
invisible(sapply(my_packages, install_if_missing))

myfile.R

# taken from example on https://www.rplumber.io/

#* @get /mean
normalMean <- function(samples=10){
  data <- rnorm(samples)
  mean(data)
}

#* @post /sum
addTwo <- function(a, b){
  as.numeric(a) + as.numeric(b)
}

Procfile

web: R -f /app/app.R --gui-none --no-save