streaming write with `Readable.from`

lib/storage.js

@@ -10,6 +10,7 @@ const fs = require('fs')
 const path = require('path')
 const async = require('async')
 const storage = {}
+const { Readable } = require('stream')
 
 // eslint-disable-next-line node/no-callback-literal
 storage.exists = (path, cb) => fs.access(path, fs.constants.F_OK, (err) => { cb(!err) })
@@ -90,17 +91,20 @@ storage.crashSafeWriteFileLines = (filename, lines, callback = () => {}) => {
     cb => {
       try {
         const stream = fs.createWriteStream(tempFilename)
-        const next = () => {
-          const line = lines.shift()
-          if (line === undefined) {
-            stream.close(cb)
-          } else {
+        const readable = Readable.from(lines)
+        readable.on('data', (line) => {
+          try {
             stream.write(line)
             stream.write('\n')
-            setImmediate(next)
+          } catch (err) {
+            cb(err)
           }
-        }
-        next()
+        })
+        readable.on('end', () => {
+          stream.close(cb)
+        })
+        readable.on('error', () => cb)
+        stream.on('error', () => cb)
       } catch (err) {
         cb(err)
       }