File download examples¶

Download this notebook from GitHub (right-click to download).

File Download Example¶

The purpose of this notebook is to provide code examples and code snippets that enable you to quickly add FileDownload to your Panel dashboard or application.

import numpy as np
import pandas as pd
import panel as pn
from io import BytesIO

pn.extension(sizing_mode="stretch_width")

Source: Pandas DataFrame¶

data=pd.DataFrame(np.random.randn(100, 4), columns=list('ABCD'))

Target: `.csv`¶

def get_csv():
    return BytesIO(data.to_csv().encode())

file_download_csv = pn.widgets.FileDownload(filename="data.csv", callback=get_csv, button_type="primary")
file_download_csv

Target: `.csv.zip`¶

def get_csv_zip():
    output = BytesIO()
    output.name = "data.csv"
    data.to_csv(output, compression="zip")
    output.seek(0)
    return output

file_download_csv_zip = pn.widgets.FileDownload(filename="data.csv.zip", callback=get_csv_zip, button_type="primary")
file_download_csv_zip

Target: `.xlsx`¶

Please note you need to install one of the packages

XlsxWriter or
OpenPyXL

to be able to use the .to_excel method of a DataFrame.

def get_xlsx():
    output = BytesIO()
    writer = pd.ExcelWriter(output, engine='xlsxwriter')
    data.to_excel(writer, sheet_name="Data")
    writer.save() # Important!
    output.seek(0) # Important!
    return output

file_download_xlsx = pn.widgets.FileDownload(filename="data.xlsx", callback=get_xlsx, button_type="primary")
file_download_xlsx

Target: `.json`¶

def get_json():
    return BytesIO(data.to_json(orient="records").encode())

file_download_json = pn.widgets.FileDownload(filename="data.json", callback=get_json, button_type="primary")
file_download_json

Target: `.parquet`¶

Please note you need to have the pyarrow package installed for this to work.

def get_parquet():
    output = BytesIO()
    output.name = "data.parquet"
    data.to_parquet(output)
    output.seek(0)
    return output

file_download_parquet = pn.widgets.FileDownload(filename="data.parquet", callback=get_parquet, button_type="primary")
file_download_parquet

Contributions¶

Example Contributions are very welcome. For example for DataFrame to html or pdf.

App¶

Lets wrap it into nice template that can be served via panel serve file_download_examples.ipynb

pn.template.FastListTemplate(
    site="Panel", 
    title="File Download", 
    main=[
        "This app demonstrates how to **download a Pandas DataFrame** using different formats.",
        pn.Column(
            pn.pane.HTML("<div style='font-size: 100px;text-align: center'>🐼</div>", height=75, margin=(50,5,10,5)),
            file_download_csv, file_download_csv_zip, file_download_xlsx, file_download_json, file_download_parquet),
    ], main_max_width="768px",
).servable();

This web page was generated from a Jupyter notebook and not all interactivity will work on this website. Right click to download and run locally for full Python-backed interactivity.

Download this notebook from GitHub (right-click to download).

Defer data load Iris kmeans

File download examples¶