app.py

import gradio as gr
import matplotlib.pyplot as plt
from matplotlib.dates import date2num
import numpy as np
import io
from PIL import Image
import pandas as pd

def countvis(fobj):

    df = pd.read_csv(fobj.name, sep=",")

    dates = pd.to_datetime(df['date']).dt.date.tolist()
    dates.sort()

    # Get some auxilliary values
    min_date = date2num(dates[0])
    max_date = date2num(dates[-1])
    days = int(max_date - min_date + 1)

    # Initialize X and Y axes
    x = np.arange(min_date, max_date + 1)
    y = np.zeros(days)

    # Iterate over dates, increase registration array
    for date in dates:
        index = int(date2num(date) - min_date)
        y[index] += 1
    y_sum = np.cumsum(y)

    # Plot
    plt.figure(dpi=200)
    plt.plot_date(x, y_sum, xdate=True, ydate=False, ls='-', ms=0, color='#16171E')
    plt.fill_between(x, 0, y_sum, facecolor='#D0F3FF')
    plt.xticks(rotation=15)
    plt.title('Cumulative Growth')

    img_buf = io.BytesIO()
    plt.savefig(img_buf, format='png')
    im = Image.open(img_buf)

    return im

iface = gr.Interface(fn=countvis, inputs="file", outputs="image", allow_flagging="never")

iface.launch(debug="True")