Nodejs r-script 只返回 NULL

Question

So I'm trying to run an R-script from a nodejs express REST API. I've done everything exactly as described on their Github page https://github.com/joshkatz/r-script .

The only output I get is null . Even if the R script only prints something there is no output.

.node_modules/
.routes/
...rscript.js
.index.js
.ex-sync.R

nodejs:

    const out = R("../ex-sync.R")
        .data("hello world", 20)
        .callSync();

    console.error(out);
    // null

R:

needs(magrittr)
set.seed(512)
do.call(rep, input) %>% 
  strsplit(NULL) %>% 
  sapply(sample) %>% 
  apply(2, paste, collapse = "")

Answer 1

You entered the ex-sync.R file address incorrectly, chenged to

const out = R("ex-sync.R")

Answer 2

You need to manually add R-Script folder(C:\Program Files\R\R-4.1.2\bin) to the Windows Path on This PC>Advance Settings>Environment Variables>System Variables