fix for EnableSSML and Enable per document Override

fix for EnableSSML and Enable per document Override. replace the hard values values and convert yes or True from env values to Boolean

text-to-speech/functions/src/config.ts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import {AudioEncoding, SsmlVoiceGender} from './types';
+import { AudioEncoding, SsmlVoiceGender } from './types';
 
 interface Config {
   location: string;
@@ -29,18 +29,23 @@ interface Config {
   voiceName: string;
 }
 
+function parseBoolean(value?: string): boolean {
+  if (!value) return false; // Default to false if the value is undefined or empty
+  const normalized = value.trim().toLowerCase();
+  return normalized === 'true' || normalized === 'yes';
+}
+
 const config: Config = {
-  location: process.env.LOCATION,
-  collectionPath: process.env.COLLECTION_PATH,
-  ssml: process.env.SSML === 'yes',
-  languageCode: process.env.LANGUAGE_CODE,
+  location: process.env.LOCATION || '',
+  collectionPath: process.env.COLLECTION_PATH || '',
+  ssml: parseBoolean(process.env.ENABLE_SSML), // Use parseBoolean for flexible handling
+  languageCode: process.env.LANGUAGE_CODE || 'en-US',
   audioEncoding: process.env.AUDIO_ENCODING as unknown as AudioEncoding,
   ssmlGender: process.env.SSML_GENDER as unknown as SsmlVoiceGender,
-  bucketName: process.env.BUCKET_NAME,
-  storagePath: process.env.STORAGE_PATH,
-  enablePerDocumentOverrides:
-    process.env.ENABLE_PER_DOCUMENT_OVERRIDES === 'yes',
-  voiceName: process.env.VOICE_NAME,
+  bucketName: process.env.BUCKET_NAME || 'default-bucket',
+  storagePath: process.env.STORAGE_PATH || '',
+  enablePerDocumentOverrides: parseBoolean(process.env.ENABLE_PER_DOCUMENT_OVERRIDES),
+  voiceName: process.env.VOICE_NAME || '',
 };
 
 export default config;