django-scaler 0.2

安装

1. 将 django-scaler 安装或添加到您的Python路径。

2. 将 scaler 添加到您的 INSTALLED_APPS 设置。

3. 将 scaler.middleware.ScalerMiddleware 添加到您的 MIDDLEWARE_CLASSES 设置的顶部。

4. 将 (r’^scaler/’, include(‘scaler.urls’)) 添加到 urlpatterns。

概述

服务器可能因各种原因而超载。在这种情况下，您不希望昂贵的请求使您的整个网站崩溃。当服务器超载时，网站必须将昂贵的请求重定向到“服务器繁忙”页面，然后在负载下降足够后自动删除重定向。

django-scaler 通过两种方式解决此问题。首先，它知道哪些请求需要重定向。其次，它可以指示重定向最昂贵的N个请求。它将响应时间数据存储在内存缓存中，使其能够做出这些决策。

用法

从 test_settings.py 复制

DJANGO_SCALER = {
    'server_busy_url_name': 'server-busy',

    # How many response times to consider for an URL. A small value means slow
    # response times are quickly acted upon, but it may be overly aggressive.
    # A large value means an URL must be slow for a number of requests before
    # it is acted upon. The default is 100.
    'trend_size': 10,

    # How much slower than average the trend must be before redirection kicks
    # in. The default is 4.0.
    'slow_threshold': 2.0,

    # How many seconds to keep redirecting an URL before serving normally. The
    # default is 60.
    'redirect_for': 10,

    # A function that returns how many of the slowest URLs must be redirected.
    # Depending on the site, data and load on the server this may be a large
    # number. This allows external processes to instruct the middleware to
    # redirect. The default is 0.
    'redirect_n_slowest_function': lambda: 0,

    # A function that returns what percentage of the slowest URLs must be
    # redirected. Depending on the site, data and load on the server this may
    # approach 100. The default is 0.
    'redirect_percentage_slowest_function': lambda: 0,

    # A function that returns a list of regexes. URLs matching the regexes are
    # redirected. Each regex is a simple string. Do not prefix with r''. The
    # default is an empty list.
    'redirect_regexes_function': lambda: [],
}

0.2

1. 正则表达式URL匹配用于显式重定向。

2. 最慢的显式重定向的百分比。

0.1

1. 第一个版本。