Merge pull request #2332 from hankehly/fix-piper-tts-json-payload

Fix PiperTTSService to send TTS input as JSON object

CHANGELOG.md

@@ -15,6 +15,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Fixed an issue in `LiveKitTransport` where empty `AudioRawFrame`s were pushed
   down the pipeline. This resulted in warnings by the STT processor.
+- Fixed `PiperTTSService` to send text as a JSON object in the request body,
+  resolving compatibility with Piper's HTTP API.
 
 - Fixed an issue with the `TavusVideoService` where an error was thrown due to
   missing transcription callbacks.

src/pipecat/services/piper/tts.py

@@ -84,7 +84,9 @@ class PiperTTSService(TTSService):
         try:
             await self.start_ttfb_metrics()
 
-            async with self._session.post(self._base_url, json=text, headers=headers) as response:
+            async with self._session.post(
+                self._base_url, json={"text": text}, headers=headers
+            ) as response:
                 if response.status != 200:
                     error = await response.text()
                     logger.error(