main.py

from fastapi import FastAPI, HTTPException
from fastapi.responses import HTMLResponse
from typing import List
import matplotlib.pyplot as plt
import io
import base64

app = FastAPI()

def create_chart(categories, values):
    plt.plot(categories, values)
    plt.xlabel('Categories')
    plt.ylabel('Values')
    
    # Save the plot to a BytesIO object
    img = io.BytesIO()
    plt.savefig(img, format='png')
    img.seek(0)
    plt.close()

    # Convert the BytesIO object to base64 for embedding in HTML
    img_base64 = base64.b64encode(img.read()).decode("utf-8")
    return f'<img src="data:image/png;base64,{img_base64}"/>'

@app.post("/form/")
async def show_chart(data: List[dict]):
    categories = [item["category"] for item in data]
    values = [item["value"] for item in data]

    return HTMLResponse(content=create_chart(categories, values), status_code=200)

@app.get("/visualization/", response_class=HTMLResponse)
async def show_visualization():
    # For simplicity, I'm assuming you have two lists of categories and values
    # Modify this part based on your actual data structure
    categories = ["Category1", "Category2", "Category3"]
    values = [10, 20, 30]

    return HTMLResponse(content=create_chart(categories, values), status_code=200)