使用 Python Flask 应用程序时发生“运行时错误：在应用程序上下文之外工作”（使用调度程序发送 gmail）

Question

app = Flask(__name__)

app.config.update(
    MAIL_SERVER = 'smtp.gmail.com',
    MAIL_PORT = 465,
    MAIL_USE_SSL = True,
    MAIL_USE_TLS = False,
    MAIL_USERNAME = '******',
    MAIL_PASSWORD = '******'
)

mail = Mail(app)

#CS50.net
def lookup(symbol):
    """Look up quote for symbol."""

    # Contact API
    try:
        response = requests.get(f"https://api.iextrading.com/1.0/stock/{urllib.parse.quote_plus(symbol)}/quote")
        response.raise_for_status()
    except requests.RequestException:
        return None

    # Parse response
    try:
        quote = response.json()
        return {
            "name": quote["companyName"],
            "price": float(quote["latestPrice"]),
            "symbol": quote["symbol"]
        }
    except (KeyError, TypeError, ValueError):
        return None


@app.route('/')
def print_date_time():
    Symbol = "PG"
    Symbol = lookup(Symbol)
    msg = mail.send_message(
        'PG',
        sender='*****',
        recipients=['******'],
        body = "PG DROP BELOW 91 buy now"
    )





scheduler = BackgroundScheduler()
scheduler.add_job(func=print_date_time, trigger="interval", seconds=10)
scheduler.start()

# Shut down the scheduler when exiting the app
atexit.register(lambda: scheduler.shutdown())

我使用 Python 使用 Flask 创建了一个应用程序，如果满足条件，它将每 10 秒向我发送一封 Gmail。当我运行应用程序时，我得到了这个：

"RuntimeError: Working outside of application context.

This typically means that you attempted to use functionality that needed
to interface with the current application object in some way. To solve
this, set up an application context with app.app_context().  See the
documentation for more information. "

我的想法是，该错误是由于我尝试通过应用程序上下文之外的 Gmail 发送消息而引起的。有任何想法吗 ？？THK

Answer 1

您的函数print_date_time正在通过应用程序上下文之外的新线程执行，并且 Mail 对象需要它。您应该将带有应用程序对象的参数传递给您的函数（装饰器路由不是必需的）。该参数的值为current_app._get_current_object().

我重新实现了你的功能print_date_time：

def print_date_time(app):
    with app.app_context():
        Symbol = "PG"
        Symbol = lookup(Symbol)
        msg = mail.send_message(
            'PG',
            sender='*****',
            recipients=['******'],
            body = "PG DROP BELOW 91 buy now"
        )