app.py

import os
import zipfile
import chromadb
from sentence_transformers import SentenceTransformer
import gradio as gr
from fastapi import FastAPI
from pydantic import BaseModel

# Extract database
DB_PATH = "./medqa_db"
if not os.path.exists(DB_PATH) and os.path.exists("./medqa_db.zip"):
    print("Extracting database...")
    with zipfile.ZipFile("./medqa_db.zip", 'r') as zip_ref:
        zip_ref.extractall(".")
    print("Extracted!")

# Load database and model
print(f"Loading database from: {DB_PATH}")
client = chromadb.PersistentClient(path=DB_PATH)
collection = client.get_collection("medqa")
print(f"Loaded {collection.count()} items")
print("Loading model...")
model = SentenceTransformer('ncbi/MedCPT-Query-Encoder')
print("Ready!")

# Search function
def search_function(query, num_results=3):
    embedding = model.encode(query).tolist()
    results = collection.query(query_embeddings=[embedding], n_results=int(num_results))
    return results

# Gradio interface
def search_gradio(query, num_results=3):
    if not query.strip():
        return "Please enter a search query."
    
    try:
        results = search_function(query, num_results)
        output = ""
        for i in range(len(results['documents'][0])):
            output += f"\n{'='*60}\nExample {i+1}\n{'='*60}\n"
            output += results['documents'][0][i] + "\n"
            output += f"\nAnswer: {results['metadatas'][0][i].get('answer', 'N/A')}\n"
            output += f"Similarity: {1 - results['distances'][0][i]:.3f}\n"
        return output
    except Exception as e:
        return f"Error: {str(e)}"

demo = gr.Interface(
    fn=search_gradio,
    inputs=[
        gr.Textbox(label="Medical Query", placeholder="e.g., hyponatremia", lines=2),
        gr.Slider(1, 5, value=3, step=1, label="Number of Results")
    ],
    outputs=gr.Textbox(label="Similar USMLE Questions", lines=20),
    title="MedQA Search",
    description="Search for similar USMLE Step 1 questions",
    examples=[["hyponatremia", 3], ["myocardial infarction", 2]]
)

# FastAPI for ChatGPT
app = FastAPI()

class SearchRequest(BaseModel):
    query: str
    num_results: int = 3

class SearchResponse(BaseModel):
    results: list[dict]

@app.post("/search_medqa")
async def api_search(request: SearchRequest):
    results = search_function(request.query, request.num_results)
    formatted = []
    for i in range(len(results['documents'][0])):
        formatted.append({
            "example_number": i + 1,
            "question": results['documents'][0][i],
            "answer": results['metadatas'][0][i].get('answer', 'N/A'),
            "distance": results['distances'][0][i]
        })
    return SearchResponse(results=formatted)

# Mount Gradio on FastAPI
app = gr.mount_gradio_app(app, demo, path="/")