如何通过HTML按钮在Flask中运行Python发送邮件脚本

Hey there, let's get your Flask app set up so clicking a button sends an email. Here's a straightforward, step-by-step solution that ties your HTML frontend to the email-sending backend.

1. Project Structure #

First, organize your project like this to keep things clean:

your_flask_app/
├── app.py          # Flask backend logic
├── templates/
│   └── index.html  # HTML frontend page
└── .env            # (Optional) For secure credential storage

2. Flask Backend Code (app.py) #

This code sets up a route to handle the button click, plus the core email-sending logic. We'll use Python's built-in smtplib for emails and keep sensitive info out of the code with environment variables.

from flask import Flask, render_template, request
import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
import os
from dotenv import load_dotenv  # Install via `pip install python-dotenv`

# Load sensitive data from .env file
load_dotenv()

app = Flask(__name__)

# Fetch email credentials from environment variables
EMAIL_USER = os.getenv("EMAIL_USER")
EMAIL_PASS = os.getenv("EMAIL_PASS")

def send_test_email():
    """Handles the actual email-sending process"""
    try:
        # Configure email details
        sender = EMAIL_USER
        receiver = "recipient@example.com"  # Replace with your target email
        subject = "Test Email from Flask Button"
        body = "This email was triggered by clicking a button in a Flask web app!"

        # Build the email message
        msg = MIMEMultipart()
        msg["From"] = sender
        msg["To"] = receiver
        msg["Subject"] = subject
        msg.attach(MIMEText(body, "plain"))

        # Connect to your email provider's SMTP server (Gmail example below)
        with smtplib.SMTP("smtp.gmail.com", 587) as server:
            server.starttls()  # Enable secure TLS connection
            server.login(sender, EMAIL_PASS)
            server.sendmail(sender, receiver, msg.as_string())
        
        return True  # Return success status to frontend
    except Exception as e:
        print(f"Email failed to send: {str(e)}")
        return False  # Return failure status if something goes wrong

@app.route("/")
def home():
    # Render the main page
    return render_template("index.html")

@app.route("/send-email", methods=["POST"])
def trigger_email():
    # This route runs when the button is clicked
    email_sent = send_test_email()
    # Pass the result back to the template for user feedback
    return render_template("index.html", email_sent=email_sent)

if __name__ == "__main__":
    app.run(debug=True)

3. HTML Frontend (templates/index.html) #

This simple page has a button that submits a form to our Flask route, plus feedback to let the user know if the email sent successfully.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Send Email with Flask</title>
</head>
<body>
    <h1>Click the Button to Send an Email</h1>
    
    <!-- Form that sends a POST request to our /send-email route -->
    <form method="POST" action="/send-email">
        <button type="submit">Send Test Email</button>
    </form>

    <!-- Show success/failure message after submission -->
    {% if email_sent is defined %}
        {% if email_sent %}
            <p style="color: green; margin-top: 10px;">✅ Email sent successfully!</p>
        {% else %}
            <p style="color: red; margin-top: 10px;">❌ Failed to send email. Check server logs for details.</p>
        {% endif %}
    {% endif %}
</body>
</html>

4. Key Setup Steps & Notes #

• Secure Credential Storage: Create a .env file in your project root with these lines (replace with your actual info):

  EMAIL_USER=your-email@gmail.com
  EMAIL_PASS=your-app-password  # For Gmail, use an App Password if 2FA is enabled
  

• SMTP Provider Adjustments: Tweak the SMTP server details in send_test_email() for your email service:
  • Outlook/Office 365: smtp.office365.com:587
  • Yahoo: smtp.mail.yahoo.com:587
  • 163/126 Mail: smtp.163.com:25
• Install Dependencies: Run pip install flask python-dotenv to get the required packages.
• Production Warning: Never use debug=True in a live production environment—it exposes sensitive data.

5. Test It Out #

1. Run python app.py to start the Flask server.
2. Open http://localhost:5000 in your browser.
3. Click the "Send Test Email" button. You'll see a success/failure message, and the email should arrive in the recipient's inbox (check spam if it doesn't show up immediately).

内容的提问来源于stack exchange，提问作者Seong