utils.py

import streamlit as st
import pickle
import pandas as pd
import json
import base64
import uuid
import re
import jupytext

from bokeh.models.widgets import Div
import math


def notebook_header(text):
    """
    Insert section header into a jinja file, formatted as notebook cell.
    
    Leave 2 blank lines before the header.
    """
    return f"""# # {text}
"""


def code_header(text):
    """
    Insert section header into a jinja file, formatted as Python comment.
    
    Leave 2 blank lines before the header.
    """
    seperator_len = (75 - len(text)) / 2
    seperator_len_left = math.floor(seperator_len)
    seperator_len_right = math.ceil(seperator_len)
    return f"# {'-' * seperator_len_left} {text} {'-' * seperator_len_right}"


def to_notebook(code):
    """Converts Python code to Jupyter notebook format."""
    notebook = jupytext.reads(code, fmt="py")
    return jupytext.writes(notebook, fmt="ipynb")


def open_link(url, new_tab=True):
    if new_tab:
        js = f"window.open('{url}')"  # New tab or window
    else:
        js = f"window.location.href = '{url}'"  # Current tab
    html = '<img src onerror="{}">'.format(js)
    div = Div(text=html)
    st.bokeh_chart(div)


def download_button(
    object_to_download, download_filename, button_text 
):
    try:
        # some strings <-> bytes conversions necessary here
        b64 = base64.b64encode(object_to_download.encode()).decode()
    except AttributeError as e:
        b64 = base64.b64encode(object_to_download).decode()

    button_uuid = str(uuid.uuid4()).replace("-", "")
    button_id = re.sub("\d+", "", button_uuid)

    custom_css = f""" 
        <style>
            #{button_id} {{
                display: inline-flex;
                align-items: center;
                justify-content: center;
                background-color: rgb(255, 255, 255);
                color: rgb(38, 39, 48);
                padding: .25rem .75rem;
                position: relative;
                text-decoration: none;
                border-radius: 4px;
                border-width: 1px;
                border-style: solid;
                border-color: rgb(230, 234, 241);
                border-image: initial;
            }} 
            #{button_id}:hover {{
                border-color: rgb(246, 51, 102);
                color: rgb(246, 51, 102);
            }}
            #{button_id}:active {{
                box-shadow: none;
                background-color: rgb(246, 51, 102);
                color: white;
                }}
        </style> """

    dl_link = (
        custom_css
        + f'<a download="{download_filename}" id="{button_id}" href="data:file/txt;base64,{b64}">{button_text}</a><br><br>'
    )

    st.markdown(dl_link, unsafe_allow_html=True)