🟡 [Enhancement] Add REST API layer using FastAPI for programmatic access

[AkshatRaj00]

Feature Request

Summary

Currently VisaIQ is only accessible via the Streamlit UI. Adding a FastAPI layer would allow:

• Mobile app integration (Flutter client)
• Third-party integrations
• Programmatic batch predictions

Proposed Implementation

# api.py
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel
from predict import predict_with_confidence

app = FastAPI(title="VisaIQ API", version="1.0.0")

class PredictionRequest(BaseModel):
    country: str
    visa_type: str
    application_date: str  # YYYY-MM-DD

class PredictionResponse(BaseModel):
    days: float
    lower: float
    upper: float
    confidence: float
    confidence_label: str

@app.post("/predict", response_model=PredictionResponse)
def predict(req: PredictionRequest):
    result, error = predict_with_confidence(req.dict())
    if error:
        raise HTTPException(status_code=422, detail=error)
    return result

@app.get("/health")
def health():
    return {"status": "ok", "model_loaded": MODEL_LOADED}

Deploy alongside Streamlit:

uvicorn api:app --port 8001 &
streamlit run app.py --port 8501

Use Cases

• Flutter mobile app for VisaIQ
• Agency dashboard integrations
• Automated batch processing scripts

enhancement api fastapi integration