如何将 Content-disposition header 设置为文件部分的附件？

Question

我正在使用 Python 请求模块发送包含 form-data 和文件附件的 multi-part HTTP POST 请求。

每个multi-partobject的"Content-disposition"header设置为"form-data"，包括文件部分。

我需要 "Content-disposition" header 用于 form-data 部分仍然说 "form-data"，但 "Content-disposition" header 用于文件部分必须说 "attachment" 而不是 "form-data".

如何仅将 content-disposition header 更改为 file-part？

我的代码：

#Python 3.7.3 (default, Apr 24 2019, 13:20:13) [MSC v.1915 32 bit (Intel)]
import requests

#USER PARAMETERS
user_name = 'user_account'
password = 'user_password'
token = '45Hf4xGhj'

#REQUESTS PARAMETERS
url = '192.168.0.2'
headers = {'content-type': 'multi-part/form-data'}
data = {'Username':user_name, 'Password':password, 'Token':token}
files = {'settings': ('settings.xml', open('settings.xml', 'rb'), 'app/xml')}

#POST
response = requests.post(url, headers=headers, data=data, files=files)

这是 file-part 的 header 在 Python 请求下的样子：

Content-Type: app/xml
Content-Disposition: form-data; name="settings"; filename="settings.xml"

这就是我需要 file-part 的 header 的样子：

Content-Type: app/xml
Content-Disposition: attachment; name="settings"; filename="settings.xml"

我还尝试通过向文件添加 header 参数来更改 header：

files = {'settings': ('settings.xml', open('settings.xml', 'rb'),
         'app/xml', {'Content-Disposition':'attachment'})}

但这没有效果。我可以指定任何其他自定义 header，它会添加它，但如果我使用该方法，它不会更改 "Content-Disposition" header。

有什么想法吗？

使用工具带：

m = MultipartEncoder( fields={'Username': user_name, 
                              'Password': password, 
                              'Token': token, 
                    'settings': ('settings', open('settings.xml', 'rb'), 
                                 'app/xml', 
                                {'Content-Disposition':'attachment'}
                                )
                             } 
                    ) 

r = requests.post('http://httpbin.org/post', 
                   data=m, 
                   headers={'Content-Type': m.content_type})

results in

...--2ba9624051854b6d961bad262a1792fc 
Content-Disposition: form-data; name="settings"; filename="settings"
Content-Type: app/xml 
<?xml version="1.0" encoding="utf-16"?>...

Answer 1

Question: Set Content-disposition header as attachment for file part?

简短的回答：使用 python-requests，这是不可能的，现在的实现方式。

Explanation:

requests/models.py
class RequestEncodingMixin(object):
    ...
    def _encode_files(files, data):
        ...
        rf = RequestField(name=k, data=fdata, filename=fn, headers=fh)
        rf.make_multipart(content_type=ft)
Variable fh holdes the 4th tuple item passed from
files = {'settings': (filename, io.BytesIO(b'some,data,to,send\nanother,row,to,send\n'),
         'app/xml', {'Content-Disposition':'attachment'} )}
The rf.header dict get updated passing headers=fh with 'Content-Disposition':....
Calling rf.make_multipart(content_type=ft), at the next line, only passing the 3trd tuple item.

The method make_multipart - urllib3/fields.py is defined as
def make_multipart(
    self, content_disposition=None, content_type=None, content_location=None
):
    self.headers["Content-Disposition"] = content_disposition or u"form-data"
    ...
which replaces self.headers["Content-Disposition"] with the default u"form-data".

Possible Solutions:

只用urllib3你可以做到

rf.make_multipart(content_disposition=fh.get("Content-Disposition"), content_type=ft)

向 urllib3 and/or python-requests 提出请求以解决此问题。
给自己打补丁，requests/models.py 或 urlib3/fields。

Patch: def make_multipart

仅添加默认值 Content-Disposition: form-data（如果 self.headers 中还没有）。

from urllib3 import fields

def make_multipart(
        self, content_disposition=None, content_type=None, content_location=None
    ):
        if self.headers.get("Content-Disposition") is None:
            self.headers["Content-Disposition"] = content_disposition or u"form-data"

        self.headers["Content-Disposition"] += u"; ".join(
            [
                u"",
                self._render_parts(
                    ((u"name", self._name), (u"filename", self._filename))
                ),
            ]
        )
        self.headers["Content-Type"] = content_type
        self.headers["Content-Location"] = content_location

fields.RequestField.make_multipart = make_multipart

Resulting multipart:

--e96a4935b8d5b2355f1da3070faa4b28
Content-Disposition: attachment; name="settings"; filename="settings.xml"
Content-Type: app/xml

some,data,to,send
another,row,to,send

--e96a4935b8d5b2355f1da3070faa4b28--

测试 Python: 3.5 - urllib3: 1.23 - 请求: 2.19.1

如何将 Content-disposition header 设置为文件部分的附件？

how to set Content-disposition header as attachment for file part?

python

content-disposition

python-requests