init

lib/datafile.js

@@ -0,0 +1,31 @@
+const fs = require('fs')
+const os = require('os')
+const { Transform } = require('stream')
+
+module.exports = function(filename='data.json', onFinish=()=>{}) {
+  //
+  // Create an object to string transform
+  // stream
+  //
+  var stream = new Transform({
+    writableObjectMode: true,
+
+    transform(chunk, encoding, callback) {
+      this.push(JSON.stringify(chunk))
+      this.push(os.EOL)
+      return callback()
+    }
+  })
+  //
+  // Pipe that to the file write
+  // stream and set up an onFinish
+  // handler
+  //
+  stream.pipe(
+    fs.createWriteStream(filename).on('finish', onFinish)
+  )
+  //
+  // Return the new write stream
+  //
+  return stream
+}