urllib.request.urlopen() 是做什么的？

Question

在 python 3 中，urllib.request 模块的 urlopen 函数会检索 URL 的目标，或者只是打开与 URL 的连接作为文件句柄，或者具有我完全失去了它？我想了解它是如何工作的。

基本上我想知道从 URL 下载文件所花费的时间。我该怎么做？

这是我的代码：

版本 1

import urllib
import time

start = time.time()
with urllib.request.urlopen('http://mirror.hactar.bz/lastsync') as f:
    lastsync = f.read() #Do i need this line if i dont care about the data
    end = time.time()
duration = end - start

版本 2

import urllib
import time

with urllib.request.urlopen('http://mirror.hactar.bz/lastsync') as f:
    start = time.time()
    lastsync = f.read() #Does this line do the actual data retrieval ?
    end = time.time()
duration = end - start

Answer 1

来自docs：

Open the URL url, which can be either a string or a Request object.

...

This function returns a file-like object with three additional methods:

geturl() — return the URL of the resource retrieved, commonly used to determine if a redirect was followed

info() — return the meta-information of the page, such as headers, in the form of an mimetools.Message instance (see Quick Reference to HTTP Headers)

getcode() — return the HTTP status code of the response.

另请注意，从 Python 3.0 开始，urllib.request.urlopen() 和 urllib.urlopen() 是等效的。

编辑所以，time 它：

# urllib.request for < python 3.0
import urllib
import time

start = time.time()

# urllib.request.urlopen() for < python 3.0
response = urllib.urlopen('http://example.com/')
data = response.read() # a `bytes` object
end = time.time()

duration = end - start

urllib.request.urlopen() 是做什么的？

what does urllib.request.urlopen() do?

python

urllib