如何计算python脚本使用了多少网络IO？

Question

假设我们有以下文件script.py

import requests

response = requests.get("https://example.com")

我可以通过测量response的大小来估计我已经使用了多少网络带宽。

但是如果脚本更复杂呢？这个脚本现在是一个极其复杂的二手文件，它使用了一堆不同的库。该脚本在处理信息并通过同一目录中的json文件返回结果之前，从各种不同的网站获取信息。

现在，我如何找出脚本每次运行使用了多少网络带宽？

Answer 1

如果你想把事情做好，你必须自己去做。

# the following module imports are in-built

# the following module imports are in-house

# the following module imports are 3rd-party
import requests

total_sent_length = 0
total_recv_length = 0

get_sent_length   = 0
get_recv_length   = 0

post_sent_length  = 0
post_recv_length  = 0

old_request_method_get  = requests.get
old_request_method_post = requests.post

def format_size(bytes, suffix='B'):
    """
    return bytes in a human readable format
    """
    for unit in ['', 'K', 'M', 'G', 'T', 'P', 'E', 'Z']:
        if abs(bytes) < 1024.0:
            return '%3.1f%s%s' % (bytes, unit, suffix)
        bytes /= 1024.0

    return '%.1f%s%s' % (bytes, 'Y', suffix)

def rlen(response):
    """
    approximate request size sent to server
    """
    len_of_meth = len(response.request.method)
    len_of_addr = len(response.request.url)
    len_of_head = len('\r\n'.join('{}{}'.format(k, v) for k, v in response.request.headers.items()))
    len_of_body = len(response.request.body if response.request.body else [])

    return len_of_meth + len_of_addr + len_of_head + len_of_body

def patched_get(*args, **kwargs):
    """
    delegate functionality and record stats
    """
    global total_sent_length
    global total_recv_length

    global get_sent_length
    global get_recv_length

    response = old_request_method_get(*args, **kwargs)

    total_sent_length += rlen(response)
    total_recv_length += len(response.content)

    get_sent_length += rlen(response)
    get_recv_length += len(response.content)

    return response

def patched_post(*args, **kwargs):
    """
    delegate functionality and record stats
    """
    global total_sent_length
    global total_recv_length

    global post_sent_length
    global post_recv_length

    response = old_request_method_post(*args, **kwargs)

    total_sent_length += rlen(response)
    total_recv_length += len(response.content)

    post_sent_length += rlen(response)
    post_recv_length += len(response.content)

    return response

requests.get  = patched_get
requests.post = patched_post

print('total_sent_length', format_size(total_sent_length))
print('total_recv_length', format_size(total_recv_length))

resp1 = requests.get('http://www.example.com/')
resp2 = requests.get('http://www.example.com/')

print('total_sent_length', format_size(total_sent_length))
print('total_recv_length', format_size(total_recv_length))

下面是示例结果

total_sent_length 0.0B
total_recv_length 0.0B
total_sent_length 242.0B
total_recv_length 2.5KB