In a R plumber script in which I use future I need to assign some variables to the global environment (so that a variable created in one API can be retrieved from another API) but it does not work as expected.
I created a simple example. Here you can see the main script to run in R:
### Set the asynchronous coding
library(promises) ; library(future)
future::plan("multisession")
## Plumber app
library(plumber)
pr <- pr("APIs_TestAsync.R")
pr %>% pr_run()
and here the script to save as "APIs_TestAsync.R":
#* Test 1
#* @get test1
#* @serializer unboxedJSON
#* @tag TestFuture
function() {
# Create a dataset
df<-data.frame(A=c("a", "a", "a", "b", "b", "c"), B=c(1,2,3,4,5,6))
assign("Test1", df, .GlobalEnv)
return(
list(SUM=sum(df$B))
)
}
#* Test 2
#* @get test2
#* @serializer unboxedJSON
#* @tag TestFuture
function() {
# Create a future promise
Prom<-future({
# Wait for 10 seconds (needed to test the asynchronous functions)
Sys.sleep(10)
# Create a dataset
df<-data.frame(A=c("a", "a", "a", "b", "b", "c"), B=c(1,2,3,4,5,6))
assign("Test2", df, .GlobalEnv)
# Store the list in Prom
return(
list(SUM=sum(df$B))
)
}, seed=T) # Close future promise
return(Prom) # Return Prom to the API
}
You'll see that the first API (not using future) manages to assign Test1 to the global environment but that the second API does not assign Test2.
I tried several ways of assignment, different environment names, explored the futureAssign function but did not manage to make it work...
If you have any idea it would be greatly appreciated!
