如何使用请求下载图像 [英] How to download image using requests

问题描述

我正在尝试使用 python 的 requests 模块从网络下载并保存图像.

I'm trying to download and save an image from the web using python's requests module.

这是我使用的(工作)代码:

Here is the (working) code I used:

img = urllib2.urlopen(settings.STATICMAP_URL.format(**data))
with open(path, 'w') as f:
    f.write(img.read())

这是使用 requests 的新(非工作)代码:

Here is the new (non-working) code using requests:

r = requests.get(settings.STATICMAP_URL.format(**data))
if r.status_code == 200:
    img = r.raw.read()
    with open(path, 'w') as f:
        f.write(img)

你能帮我了解 requests 使用响应中的什么属性吗?

Can you help me on what attribute from the response to use from requests?

推荐答案

您可以使用 response.raw 文件对象，或迭代响应.

You can either use the response.raw file object, or iterate over the response.

默认情况下，使用 response.raw 类文件对象不会解码压缩响应(使用 GZIP 或 deflate).您可以通过将 decode_content 属性设置为 True(requests 将其设置为 False控制解码本身).然后您可以使用 shutil.copyfileobj() 让 Python 将数据流式传输到文件对象:

To use the response.raw file-like object will not, by default, decode compressed responses (with GZIP or deflate). You can force it to decompress for you anyway by setting the decode_content attribute to True (requests sets it to False to control decoding itself). You can then use shutil.copyfileobj() to have Python stream the data to a file object:

import requests
import shutil

r = requests.get(settings.STATICMAP_URL.format(**data), stream=True)
if r.status_code == 200:
    with open(path, 'wb') as f:
        r.raw.decode_content = True
        shutil.copyfileobj(r.raw, f)        

要迭代响应，请使用循环；像这样迭代确保数据在这个阶段被解压:

To iterate over the response use a loop; iterating like this ensures that data is decompressed by this stage:

r = requests.get(settings.STATICMAP_URL.format(**data), stream=True)
if r.status_code == 200:
    with open(path, 'wb') as f:
        for chunk in r:
            f.write(chunk)

这将读取 128 字节块中的数据；如果您觉得其他块大小效果更好，请使用 Response.具有自定义块大小的 iter_content() 方法:

This'll read the data in 128 byte chunks; if you feel another chunk size works better, use the Response.iter_content() method with a custom chunk size:

r = requests.get(settings.STATICMAP_URL.format(**data), stream=True)
if r.status_code == 200:
    with open(path, 'wb') as f:
        for chunk in r.iter_content(1024):
            f.write(chunk)

请注意，您需要以二进制模式打开目标文件，以确保 python 不会尝试为您翻译换行符.我们还设置了 stream=True 以便 requests 不会先将整个图像下载到内存中.

Note that you need to open the destination file in binary mode to ensure python doesn't try and translate newlines for you. We also set stream=True so that requests doesn't download the whole image into memory first.

这篇关于如何使用请求下载图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！