equivalence of -d parameter in curl in httr package of R - r

Question

I'm following the official manual of opencpu package in R. In chapter 4.3 Calling a function It uses curl to test API:
curl http://your.server.com/ocpu/library/stats/R/rnorm -d "n=10&mean=100"
and the sample output is:
/ocpu/tmp/x032a8fee/R/.val
/ocpu/tmp/x032a8fee/stdout
/ocpu/tmp/x032a8fee/source
/ocpu/tmp/x032a8fee/console
/ocpu/tmp/x032a8fee/info
I can use curl to get similar result, but when I try to send this http request using httr package in R, I don't know how to replicate the result. Here is what I tried:
resp <- POST(
url = "localhost/ocpu/library/stats/R/rnorm",
body= "n=10&mean=100"
)
resp
the output is:
Response [HTTP://localhost/ocpu/library/stats/R/rnorm]
Date: 2015-10-16 00:51
Status: 400
Content-Type: text/plain; charset=utf-8
Size: 30 B
No Content-Type header found.
I guess I don't understand what's the equivalence of curl -d parameter in httr, how can I get it correct?

Answer 1

Try this :)
library(httr)
library(jsonlite)
getFunctionEndPoint <- function(url, format) {
return(paste(url, format, sep = '/'))
}
resp <- POST(
url = getFunctionEndPoint(
url = "https://public.opencpu.org/ocpu/library/stats/R/rnorm",
format = "json"),
body = list(n = 10, mean = 100),
encode = 'json')
fromJSON(rawToChar(resp$content))