Add spoken language identification for node-addon-api (#872)

scripts/node-addon-api/lib/spoken-language-identification.js

@@ -0,0 +1,30 @@
+const addon = require('./addon.js');
+const non_streaming_asr = require('./non-streaming-asr.js');
+
+class SpokenLanguageIdentification {
+  constructor(config) {
+    this.handle = addon.createSpokenLanguageIdentification(config);
+    this.config = config;
+  }
+
+  createStream() {
+    return new non_streaming_asr.OfflineStream(
+        addon.createSpokenLanguageIdentificationOfflineStream(this.handle));
+  }
+
+  // return a string containing the language code (2 characters),
+  // e.g., en, de, fr, es, zh
+  // en -> English
+  // de -> German
+  // fr -> French
+  // es -> Spanish
+  // zh -> Chinese
+  compute(stream) {
+    return addon.spokenLanguageIdentificationCompute(
+        this.handle, stream.handle);
+  }
+}
+
+module.exports = {
+  SpokenLanguageIdentification,
+}