fix: update audio processing endpoint to accept options as JSON string and validate input

app/routes/data_processing.py

@@ -6,7 +6,8 @@ import time
 from collections import defaultdict
 from fastapi import APIRouter, File, UploadFile, Form, HTTPException, Request, Depends, status
 from fastapi.responses import StreamingResponse
-from pydantic import Json
+from pydantic import ValidationError
+import json
 import logging
 
 from app.schemas import AudioAugmentationOptions
@@ -45,7 +46,7 @@ async def _process_rate_limit(request: Request) -> None:
 @router.post("/audio", dependencies=[Depends(_process_rate_limit)])
 async def process_audio_endpoint(
     file: UploadFile = File(...),
-    options: Json[AudioAugmentationOptions] = Form(...)
+    options: str = Form(...)
 ):
     """
     Process an audio file with the given augmentation options.
@@ -54,6 +55,15 @@ async def process_audio_endpoint(
     MAX_PAYLOAD_BYTES = 30 * 1024 * 1024  # 30 MB
     logger.info(f"Received audio processing request for file: {file.filename}")
 
+    # Parse options JSON string into validated Pydantic model
+    try:
+        parsed_options = AudioAugmentationOptions.model_validate_json(options)
+    except (ValidationError, json.JSONDecodeError) as e:
+        raise HTTPException(
+            status_code=422,
+            detail={"code": "invalid_options", "message": f"Invalid options format: {e}"}
+        )
+
     if not file.content_type or not file.content_type.startswith("audio/"):
         raise HTTPException(status_code=400, detail={"code": "invalid_file_type", "message": "Invalid file type. Must be audio."})
 
@@ -73,7 +83,7 @@ async def process_audio_endpoint(
         content = b"".join(chunks)
 
         # Process audio
-        processed_audio = process_audio(content, options)
+        processed_audio = process_audio(content, parsed_options)
 
         # Return as downloadable file
         filename = f"processed_{file.filename}.wav"