关于 flask-mail 部署在云端 nginx服务器上 504 Gateway Time-out 超时问题

def send_email(app, msg):
    with app.app_context():
        try:
            mail.send(msg)
        except Exception as e:
            print(e)
            pass


# 发送邮件
class Get_email_captcha(Resource):
    def get(self):
        email = request.args.get("email")
        print(email)
        captcha = str(random.randint(1000, 9999))
        message = Message(subject="xxx·注册验证码",
                          recipients=[email],
                          body=f"您的验证码是: {captcha}")

        # 验证码存储
        redis_client.set("captcha", captcha)
        print(redis_client.get("captcha"))

        # 发送邮件异步优化
        Thread(target=send_email, args=[current_app._get_current_object(), message]).start()

        return jsonify({"code": 200, "message": "", "data": None})

import datetime
from flask import Flask, session, g, make_response
import config
from exts import db, cors, migrate, socketio, mail, api, auth
from models import UserModel
from blueprints.qa.qa import bp as qa_bp
from blueprints.auth.auth import bp as auth_bp
from utils.jwt import jwt_token_required
from flask_migrate import Migrate

from flask_socketio import SocketIO, send, emit, join_room, leave_room
import eventlet


eventlet.monkey_patch()

app = Flask(__name__)

# 绑定配置文件
app.config.from_object(config)
app.config['PERMANENT_SESSION_LIFETIME'] = datetime.timedelta(days=7)
socketio.init_app(app, cors_allowed_origins='*', async_mode="threading")
cors.init_app(app, supports_credentials=True)
db.init_app(app)
migrate.init_app(app, db)
mail.init_app(app)
api.init_app(app)

from flask import Flask, session, g
import config
from exts import db, mail
from models import UserModel
from blueprints.qa import bp as qa_bp
from blueprints.auth import bp as auth_bp
from blueprints.console import bp as console_bp
from flask_migrate import Migrate

from flask_socketio import SocketIO, send, emit, join_room, leave_room

app = Flask(__name__)
# 绑定配置文件
app.config.from_object(config)
socketio = SocketIO(app)

db.init_app(app)
mail.init_app(app)

migrate = Migrate(app, db)

app.register_blueprint(qa_bp)
app.register_blueprint(auth_bp)
app.register_blueprint(console_bp)

import eventlet

eventlet.monkey_patch()