adding the logic to generate the image

backend/app/api/qr.py

@@ -0,0 +1,16 @@
+from fastapi import APIRouter, HTTPException
+from fastapi.responses import Response
+
+from app.schemas.qr import QRRequest
+from app.services.qr_service import generate_qr_image_bytes
+
+router = APIRouter()
+
+
+@router.post("/generate")
+async def generate_qr(payload: QRRequest):
+    try:
+        img_bytes = generate_qr_image_bytes(payload.text, payload.size)
+        return Response(content=img_bytes, media_type="image/png")
+    except Exception as exc:  # pragma: no cover
+        raise HTTPException(status_code=500, detail=str(exc))

backend/app/main.py

@@ -0,0 +1,24 @@
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.api.qr import router as qr_router
+
+
+def create_app() -> FastAPI:
+    app = FastAPI(title="QR Code Service")
+
+    # Open CORS to all origins
+    app.add_middleware(
+        CORSMiddleware,
+        allow_origins=["*"],
+        allow_credentials=True,
+        allow_methods=["*"],
+        allow_headers=["*"],
+    )
+
+    app.include_router(qr_router, prefix="/api/qrcode")
+
+    return app
+
+
+app = create_app()

backend/app/schemas/qr.py

@@ -0,0 +1,8 @@
+from pydantic import BaseModel, Field
+
+
+class QRRequest(BaseModel):
+    text: str = Field(..., description="Text or URL to encode into the QR code")
+    size: int = Field(
+        500, gt=0, le=2000, description="Output image size in pixels (square)"
+    )

backend/app/services/qr_service.py

@@ -0,0 +1,19 @@
+from io import BytesIO
+
+import qrcode
+
+
+def generate_qr_image_bytes(text: str, size: int = 300) -> bytes:
+    img = qrcode.make(text)
+
+    # Ensure RGB for consistent PNG output
+    if getattr(img, "mode", None) != "RGB":
+        img = img.convert("RGB")
+
+    if size:
+        img = img.resize((size, size))
+
+    buf = BytesIO()
+    img.save(buf, "PNG")
+    buf.seek(0)
+    return buf.getvalue()

backend/main.py

@@ -0,0 +1,4 @@
+import uvicorn
+
+if __name__ == "__main__":
+    uvicorn.run("app.main:app", host="0.0.0.0", port=5001, log_level="info")

backend/requirements.txt

@@ -0,0 +1,5 @@
+fastapi
+uvicorn[standard]
+qrcode
+pillow
+pydantic