Add non-streaming ASR APIs for node-addon-api (#868)

scripts/node-addon-api/lib/non-streaming-asr.js

@@ -0,0 +1,40 @@
+const addon = require('./addon.js');
+
+class OfflineStream {
+  constructor(handle) {
+    this.handle = handle;
+  }
+
+  // obj is {samples: samples, sampleRate: sampleRate}
+  // samples is a float32 array containing samples in the range [-1, 1]
+  // sampleRate is a number
+  acceptWaveform(obj) {
+    addon.acceptWaveformOffline(this.handle, obj)
+  }
+}
+
+class OfflineRecognizer {
+  constructor(config) {
+    this.handle = addon.createOfflineRecognizer(config);
+    this.config = config
+  }
+
+  createStream() {
+    const handle = addon.createOfflineStream(this.handle);
+    return new OfflineStream(handle);
+  }
+
+  decode(stream) {
+    addon.decodeOfflineStream(this.handle, stream.handle);
+  }
+
+  getResult(stream) {
+    const jsonStr = addon.getOfflineStreamResultAsJson(stream.handle);
+
+    return JSON.parse(jsonStr);
+  }
+}
+
+module.exports = {
+  OfflineRecognizer,
+}