Create app/main.py

app/main.py

@@ -0,0 +1,82 @@
+from fastapi import FastAPI, UploadFile, File, HTTPException, BackgroundTasks
+from fastapi.middleware.cors import CORSMiddleware
+import uuid
+from . import processing
+from .models import TaskStatus
+import os
+import shutil
+from pathlib import Path
+
+app = FastAPI()
+
+# Configure CORS - In production, restrict this to your frontend's domain
+origins = ["*"] 
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=origins,
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+tasks = {}
+TEMP_DIR = Path("temp_audio")
+TEMP_DIR.mkdir(exist_ok=True)
+
+# Define allowed file extensions and max size (50MB)
+ALLOWED_EXTENSIONS = {".wav", ".mp3", ".m4a", ".ogg", ".flac"}
+MAX_FILE_SIZE = 50 * 1024 * 1024 
+
+@app.post("/upload")
+async def upload_audio_file(background_tasks: BackgroundTasks, file: UploadFile = File(...)):
+    """
+    Receives an audio file, saves it temporarily to disk, and starts the 
+    processing pipeline in the background. Includes validation for file type and size.
+    """
+    # Validation: File Extension
+    file_ext = Path(file.filename).suffix.lower()
+    if file_ext not in ALLOWED_EXTENSIONS:
+        raise HTTPException(
+            status_code=400, 
+            detail=f"Invalid audio format. Allowed formats: {', '.join(ALLOWED_EXTENSIONS)}"
+        )
+    
+    # Validation: File Size
+    # We read the file into memory once to check size and then save it.
+    # This is a trade-off for validation. For extremely large files (>1GB), 
+    # a streaming validator would be better, but this is fine for a 50MB limit.
+    file_content = await file.read()
+    if len(file_content) > MAX_FILE_SIZE:
+        raise HTTPException(status_code=413, detail="File too large. Limit is 50MB.")
+    
+    # Reset file pointer before saving
+    await file.seek(0) 
+
+    task_id = str(uuid.uuid4())
+    tasks[task_id] = {"status": "processing", "result": None}
+
+    file_path = TEMP_DIR / f"{task_id}{file_ext}"
+
+    try:
+        with open(file_path, "wb") as buffer:
+            shutil.copyfileobj(file.file, buffer)
+    finally:
+        file.file.close()
+    
+    background_tasks.add_task(processing.run_pipeline, task_id, file_path, tasks)
+    
+    return {"task_id": task_id}
+
+@app.get("/status/{task_id}", response_model=TaskStatus)
+async def get_task_status(task_id: str):
+    task = tasks.get(task_id)
+    if not task:
+        raise HTTPException(status_code=404, detail="Task not found")
+    return TaskStatus(**task)
+
+@app.get("/result/{task_id}")
+async def get_task_result(task_id: str):
+    task = tasks.get(task_id)
+    if not task or task.get("status") != "complete":
+        raise HTTPException(status_code=404, detail="Result not yet available or task not found")
+    return task.get("result")