python - Flask - 蓝图 - 在第一次请求之前？

Question

我正在尝试将 before_first_request 功能添加到我的 Flask 应用程序的特定 Blueprint 中。您可以在下面看到我有两个蓝图:public 和 admin。

我已经尝试过，但没有成功:https://stackoverflow.com/a/27401269/7077556

这只适用于向应用程序发出的第一个请求，第一个请求之后来自其他设备和 IP 的任何其他请求都不会由此“自定义”before_first_request 处理。

我想仅针对客户端向公共(public)蓝图发出的第一个请求运行一个函数。

我该怎么做？提前致谢

这是我正在使用的代码:

from flask import Flask, Blueprint

application = Flask(__name__)

# PUBLIC Blueprint
public = Blueprint('public', __name__, static_url_path='/public', static_folder='static', template_folder='templates')

# ADMIN Blueprint
admin = Blueprint('admin', __name__, static_url_path='/admin', static_folder='static', template_folder='templates')


# Before First Request To Public BP
from threading import Lock
public._before_request_lock = Lock()
public._got_first_request = False

@public.before_request
def init_public_bp():
    if public._got_first_request:
        return
    else:
        with public._before_request_lock:
            public._got_first_request = True
            print('THIS IS THE FIRST REQUEST!')
            # Do more stuff here...


# PUBLIC ROUTE
@public.route("/")
def public_index():
    return 'Hello World!'

# ADMIN ROUTE
@admin.route('/')
def admin_index():
    return 'Admin Area!'

# Register PUBLIC Blueprint
application.register_blueprint(public)
# Register ADMIN Blueprint
application.register_blueprint(admin, url_prefix='/admin')

if __name__ == "__main__":
    application.run(host='0.0.0.0')

Answer 1

蓝图实例的

before_request 不是装饰器。它只是一个实例方法，在请求之前调用一个函数。您应该按以下方式使用它:

from __future__ import print_function
from flask import Flask, Blueprint

application = Flask(__name__)

# PUBLIC Blueprint
public = Blueprint('public', __name__, static_url_path='/public', static_folder='static', template_folder='templates')

# ADMIN Blueprint
admin = Blueprint('admin', __name__, static_url_path='/admin', static_folder='static', template_folder='templates')


# Before First Request To Public BP
from threading import Lock
public._before_request_lock = Lock()
public._got_first_request = False

def init_public_bp():
    if public._got_first_request:
        return  # or pass
    with public._before_request_lock:
        public._got_first_request = True
        print('THIS IS THE FIRST REQUEST!')
        # Do more stuff here...
public.before_request(init_public_bp)


# PUBLIC ROUTE
@public.route("/")
def public_index():
    return 'Hello World!'

# ADMIN ROUTE
@admin.route('/')
def admin_index():
    return 'Admin Area!'

# Register PUBLIC Blueprint
application.register_blueprint(public)
# Register ADMIN Blueprint
application.register_blueprint(admin, url_prefix='/admin')

if __name__ == "__main__":
    application.run(host='0.0.0.0')