convert-action: Adjust how stream is outputted

See also: https://stackoverflow.com/a/65233095

bin/jskos-convert

@@ -32,5 +32,6 @@ if (type) {
 
 const files = args.length ? args : ["-"]
 const options = program.opts()
+options.exitProcess = true
 
 convert(options, type, files)

lib/convert-action.js

@@ -2,18 +2,23 @@ import fs from "fs"
 import needle from "needle"
 import convert from "./jskos-convert.js"
 import { ConceptScheme } from "jskos-tools"
+import { Writable } from "stream"
 
 export default (options, type, files) => {
 
   const to = options.to || "ndjson"
-  let { scheme, destination } = options
+  let { scheme, destination, exitProcess = false } = options
 
   let registry = {}
   if (options.registry) {
     let json = JSON.parse(fs.readFileSync(options.registry))
     registry = Array.isArray(json) ? { schemes: json } : json
   }
-  const output = process.stdout
+  const output = new Writable({
+    write(chunk, encoding, callback) {
+      process.stdout.write(chunk,callback)
+    },
+  })
 
   output.on("error", err => {
     if (err.code == "EPIPE") {
@@ -30,6 +35,8 @@ export default (options, type, files) => {
     destination = new ConceptScheme(JSON.parse(fs.readFileSync(destination).toString()))
   }
 
+  let errorCode = 0, lastStream
+
   while (files.length > 0) {
     let file = files.shift()
     let input = process.stdin
@@ -58,9 +65,18 @@ export default (options, type, files) => {
       for (let i=0; i<steps.length; i++) {
         stream = stream.pipe(steps[i])
       }
-      stream.pipe(output)
+      lastStream = stream.pipe(output)
     } catch(e) {
       console.error(e.message)
+      errorCode = 1
     }
   }
+
+  // Exit process with error code if option is given
+  if (exitProcess) {
+    lastStream?.on("finish", () => {
+      process.exit(errorCode)
+    }) || process.exit(errorCode)
+  }
+
 }