python - 内容长度被剥离

Question

我使用的是 webpy 0.34，python 2.6.6。我也在使用 mimerender。我试图在我的 http 响应中包含内容长度，但由于某种原因， header 被删除。我说删除是因为我可以很好地创建自定义 header ，并且我可以在客户端上看到这些 header 。但是当我尝试设置内容长度时， header 永远不会到达客户端。我尝试过将 header 包含在 web.created 对象中(如图所示)，并且我也尝试过使用

web.header('Content-Length', len(data))

我做错了什么和/或不理解这段代码的工作原理？

render_json = lambda **args: json.JSONEncoder().encode(args)

class MyHandler:
    @mimerender(
            default = 'json',
            json = render_json,
            )
    def POST(self):
        data = "abcd"
        raise web.created(data, headers={'Content-Length': len(data)})

Answer 1

如果数据以分块形式发送(Transfer-Encoding: chunked)，则必须省略 Content-Length header ，as per RFC 2616 :

1. [snip]

2. If a Transfer-Encoding header field (section 14.41) is present and has any value other than "identity", then the transfer-length is defined by use of the "chunked" transfer-coding (section 3.6), unless the message is terminated by closing the connection.

3. If a Content-Length header field (section 14.13) is present, its decimal value in OCTETs represents both the entity-length and the transfer-length. The Content-Length header field MUST NOT be sent if these two lengths are different (i.e., if a Transfer-Encoding header field is present). If a message is received with both a Transfer-Encoding header field and a Content-Length header field, the latter MUST be ignored.