Scoping and calling Bitcoin price checker

Question

Hi I'm currently making a Bitcoin Price tracker. I have it rigged up so that it will send me an alert when Bitcoins price hits a certain point. I'm still beginner programmer, but it's working good so far.

I'm having trouble figuring out how I should scope and then call my two functions without the function calling itself over and over. The variable I need both functions to have access to is 'current_price'. What is the correct way to scope/organize then call these these so that my inner function can access my outer functions variables? Thank you!

The code:

import smtplib
import os
import requests
import json

email_user = os.environ.get('EMAIL_USER')
email_password = os.environ.get('APP_PASS')
phone_number = os.environ.get('USER_PHONE')

target_price = 20000 # set your target price in USD

def send_email():

    with smtplib.SMTP('smtp.gmail.com', 587) as smtp:
        smtp.ehlo()
        smtp.starttls()
        smtp.ehlo()

        smtp.login(email_user, email_password)

        subject = 'Bitcoin Alert: '
        body = 'Bitcoins price is ' + str(target_price) + "!"

        msg = f'Subject: {subject}\n\n{body}'

        smtp.sendmail(email_user, phone_number, msg)

def check_price():

    response = requests.get("https://api.coinbase.com/v2/prices/BTC-USD/spot")
    data = response.json()

    currency = data["data"]["base"]
    current_price = data["data"]["amount"]
    current_price = int(float(current_price)) ## converts string float to int

    if current_price > target_price:
        send_email()

    print(f'Bitcoins current price is {current_price}')
    

check_price()

Answer 1

There are two ways to do this. Global variables, often frowned upon and passing in current_price as an argument.

Global Variables - frowned upon:

import smtplib
import os
import requests
import json

email_user = os.environ.get('EMAIL_USER')
email_password = os.environ.get('APP_PASS')
phone_number = os.environ.get('USER_PHONE')

target_price = 20000 # set your target price in USD

def send_email():

    with smtplib.SMTP('smtp.gmail.com', 587) as smtp:
        smtp.ehlo()
        smtp.starttls()
        smtp.ehlo()

        smtp.login(email_user, email_password)

        subject = 'Bitcoin Alert: '
        body = 'Bitcoins price is ' + str(target_price) + "!"

        msg = f'Subject: {subject}\n\n{body}'

        smtp.sendmail(email_user, phone_number, msg)

def check_price():
    global current_price #global variable declared
    response = requests.get("https://api.coinbase.com/v2/prices/BTC-USD/spot")
    data = response.json()

    currency = data["data"]["base"]
    current_price = data["data"]["amount"]
    current_price = int(float(current_price)) ## converts string float to int

    if current_price > target_price:
        send_email()

    print(f'Bitcoins current price is {current_price}')
    

check_price()

and passing in current price:

import smtplib
import os
import requests
import json

email_user = os.environ.get('EMAIL_USER')
email_password = os.environ.get('APP_PASS')
phone_number = os.environ.get('USER_PHONE')

target_price = 20000 # set your target price in USD

current_price = 0 # declare current price

def send_email(current_price):

    with smtplib.SMTP('smtp.gmail.com', 587) as smtp:
        smtp.ehlo()
        smtp.starttls()
        smtp.ehlo()

        smtp.login(email_user, email_password)

        subject = 'Bitcoin Alert: '
        body = 'Bitcoins price is ' + str(target_price) + "!"

        msg = f'Subject: {subject}\n\n{body}'

        smtp.sendmail(email_user, phone_number, msg)

def check_price(current_price):

    response = requests.get("https://api.coinbase.com/v2/prices/BTC-USD/spot")
    data = response.json()

    currency = data["data"]["base"]
    current_price = data["data"]["amount"]
    current_price = int(float(current_price)) ## converts string float to int

    if current_price > target_price:
        send_email(current_price)

    print(f'Bitcoins current price is {current_price}')
    

check_price(current_price) #current price is passed in