如何让浏览器缓存静态文件？

Question

最近我用web.py构建我的应用，发现我的静态文件在每个请求中都被传输了。

以下是我的日志：

10.18.40.100:49458 - - [19/Jun/2014 17:03:45] "HTTP/1.1 GET /css/bootstrap.css" - 200 OK
10.18.40.100:49459 - - [19/Jun/2014 17:03:45] "HTTP/1.1 GET /css/bootstrap-responsive.css" - 200 OK
10.18.40.100:49460 - - [19/Jun/2014 17:03:45] "HTTP/1.1 GET /js/jquery-1.8.2.min.js" - 200 OK
10.18.40.100:49461 - - [19/Jun/2014 17:03:45] "HTTP/1.1 GET /js/bootstrap.js" - 200 OK
10.18.40.100:49461 - - [19/Jun/2014 17:03:45] "HTTP/1.1 GET /img/mini.png" - 200 OK
10.18.40.100:49460 - - [19/Jun/2014 17:03:45] "HTTP/1.1 GET /img/test_mini.png" - 200 OK
10.18.40.100:49460 - - [19/Jun/2014 17:03:45] "HTTP/1.1 GET /favicon.ico" - 200 OK
10.18.40.100:49460 - - [19/Jun/2014 17:03:52] "HTTP/1.1 GET /compeval" - 200 OK
10.18.40.100:49460 - - [19/Jun/2014 17:03:52] "HTTP/1.1 GET /css/bootstrap.css" - 200 OK
10.18.40.100:49458 - - [19/Jun/2014 17:03:52] "HTTP/1.1 GET /js/bootstrap.js" - 200 OK
10.18.40.100:49459 - - [19/Jun/2014 17:03:52] "HTTP/1.1 GET /js/jquery-1.8.2.min.js" - 200 OK
10.18.40.100:49461 - - [19/Jun/2014 17:03:52] "HTTP/1.1 GET /css/bootstrap-responsive.css" - 200 OK
10.18.40.100:49459 - - [19/Jun/2014 17:03:53] "HTTP/1.1 GET /img/mini.png" - 200 OK
10.18.40.100:49459 - - [19/Jun/2014 17:03:53] "HTTP/1.1 GET /img/glyphicons-halflings.png" - 200 OK
10.18.40.100:49459 - - [19/Jun/2014 17:03:53] "HTTP/1.1 GET /favicon.ico" - 200 OK
10.18.40.100:49459 - - [19/Jun/2014 17:03:58] "HTTP/1.1 GET /viewcompqlab" - 200 OK
10.18.40.100:49459 - - [19/Jun/2014 17:03:58] "HTTP/1.1 GET /css/bootstrap.css" - 200 OK
10.18.40.100:49461 - - [19/Jun/2014 17:03:58] "HTTP/1.1 GET /css/bootstrap-responsive.css" - 200 OK
10.18.40.100:49460 - - [19/Jun/2014 17:03:58] "HTTP/1.1 GET /js/bootstrap.js" - 200 OK
10.18.40.100:49458 - - [19/Jun/2014 17:03:58] "HTTP/1.1 GET /js/jquery-1.8.2.min.js" - 200 OK
10.18.40.100:49458 - - [19/Jun/2014 17:03:58] "HTTP/1.1 GET /img/mini.png" - 200 OK
10.18.40.100:49458 - - [19/Jun/2014 17:03:58] "HTTP/1.1 GET /favicon.ico" - 200 OK
10.18.40.100:49517 - - [19/Jun/2014 17:07:05] "HTTP/1.1 GET /compeval" - 200 OK
10.18.40.100:49517 - - [19/Jun/2014 17:07:05] "HTTP/1.1 GET /css/bootstrap.css" - 200 OK
10.18.40.100:49519 - - [19/Jun/2014 17:07:06] "HTTP/1.1 GET /js/jquery-1.8.2.min.js" - 200 OK
10.18.40.100:49518 - - [19/Jun/2014 17:07:06] "HTTP/1.1 GET /css/bootstrap-responsive.css" - 200 OK
10.18.40.100:49520 - - [19/Jun/2014 17:07:06] "HTTP/1.1 GET /js/bootstrap.js" - 200 OK
10.18.40.100:49520 - - [19/Jun/2014 17:07:06] "HTTP/1.1 GET /img/baidu_mini.png" - 200 OK
10.18.40.100:49518 - - [19/Jun/2014 17:07:06] "HTTP/1.1 GET /img/glyphicons-halflings.png" - 200 OK
10.18.40.100:49518 - - [19/Jun/2014 17:07:06] "HTTP/1.1 GET /favicon.ico" - 200 OK

显然，.png、.ico、.css 和 .js 文件在我的服务器中是静态且全局有效的。所以，我的问题是： 我怎样才能避免这种情况并让浏览器缓存这些静态文件，除非按 Ctrl+F5？

附录，如何在 web.py 中提供静态文件，在我的 index.py 文件中的代码如下：

"""register serve"""
urls=('/', 'index',
    '/favicon.ico','favicon',
    '/(js|css|img)/(.*)', 'static')


"""def class to support serve"""
class static:
    def GET(self, media, fn):
        rmod="r"
        if fn.endswith(".png"):
            rmod="rb"
        f = open(media+'/'+fn, rmod)
        try:
            stream = f.read()
            return stream
        except:
            f.close()
            return '404 Not Found'

class favicon:
    def GET(self):
        f = open("static/favicon.ico", 'rb')                                                                                                                                                                                                
        return f.read()  

然后在我的模板 html 文件中使用这些静态文件服务器：

<link href="css/bootstrap.css" rel="stylesheet" media="screen">
<link href="css/bootstrap-responsive.css" rel="stylesheet">
<script src="js/jquery-1.8.2.min.js"></script>
<script src="js/bootstrap.js"></script>    

Answer 1

不应通过web.py 提供静态文件。相反，您应该将您的网络服务器配置为根据对适当 URL 的请求为它们提供服务 - 一个常见的设置是提供一个 static 目录，所有静态文件都驻留在该目录中。

有关如何配置静态文件服务的详细信息将根据您的网络服务器（apache、lighttpd、...）和接口技术（fastCGI、mod_wsgi...）而有所不同。您可以在 the cookbook

的 Deployment 部分找到常用配置