Merge pull request #1 from prashantsinalkar/master

created api for R

1 files changed, 70 insertions, 0 deletions

diff --git a/plumber.R b/plumber.R
new file mode 100644
index 0000000..0f091c8
--- /dev/null
+++ b/plumber.R
@@ -0,0 +1,70 @@
+# plumber.R
+library(plumber)
+library(jsonlite)
+library(readr)
+library(futile.logger)
+library(tryCatchLog)
+library(ggplot2)
+
+# creare R directory
+dir.create(file.path("/tmp/R"), showWarnings = FALSE)
+
+#* Echo back the input
+#* @param msg The message to echo
+#* @get /echo
+function(msg="")
+{
+    list(msg = paste0("The message is: '", msg, "'"))
+}
+
+#* @serializer unboxedJSON
+#* @post /rscript
+function(code="", session_id="", R_file_id="")
+{
+    # create session directory for user
+    dir.create(file.path("/tmp/R/", session_id), showWarnings = FALSE)
+    InputFile <- paste("/tmp/R/",session_id,"/", R_file_id,".R", sep="")
+    OutputFile <- paste("/tmp/R/",session_id,"/", R_file_id,".txt", sep="")
+    RunInputFile <- paste("Rscript", InputFile, sep=" ")
+    fileConn<-file(InputFile)
+    Line1 = paste("png('/tmp/R/",session_id,"/", R_file_id,".png')\n", sep="")
+    Line2 = code
+    Line3 = "while (!is.null(dev.list()))  dev.off()"
+    writeLines(c(Line1, Line2, Line3), fileConn)
+    close(fileConn)
+    #ro <- system(RunInputFile, intern = TRUE)
+    ro <-robust.system(RunInputFile)
+    ro <- unlist(lapply(ro,function(x) if(identical(x,character(0))) ' ' else x))
+    fileConn<-file(OutputFile)
+    writeLines(paste0(ro), fileConn)
+    close(fileConn)
+    ro <- read_file(OutputFile)
+    if (file.exists(paste("/tmp/R/",session_id,"/",R_file_id,".png", sep="")) == TRUE) {
+        graph_exist <- TRUE
+    } else {
+        graph_exist <- FALSE
+    }
+    r<- list(status = "SUCCESS", code = "200", output = ro, graph_exist = graph_exist)
+    return (r)
+}
+
+#* @serializer contentType list(type='image/png')
+#* @get /file
+function(req, res, session_id="", R_file_id=""){
+  file = paste("/tmp/R/",session_id,"/",R_file_id,".png", sep="")
+  readBin(file,'raw',n = file.info(file)$size)
+}
+
+# function to run R script on system
+robust.system <- function (cmd) {
+    stderrFile = tempfile(pattern="R_robust.system_stderr", fileext=as.character(Sys.getpid()))
+    stdoutFile = tempfile(pattern="R_robust.system_stdout", fileext=as.character(Sys.getpid()))
+
+    retval = list()
+    retval$exitStatus = system(paste0(cmd, " 2> ", shQuote(stderrFile), " > ", shQuote(stdoutFile)), intern = TRUE )
+    retval$stdout = readLines(stdoutFile)
+    retval$stderr = readLines(stderrFile)
+
+    unlink(c(stdoutFile, stderrFile))
+    return(retval)
+}