卷曲如何POST多部分/表单数据数据以及如何读取flask请求中的multipart/form-data

Question

我尝试通过CURL发布multipart/form-data,其中包含,

• 一个JSON对象
• 流对象pdf和jpeg文件

  curl -i -X POST -H  
"Authorization":"eyJhbGciOiJIUzI1NiIsImV4cCI6MTQyNjcwNTY4NiwiaWF0IjoxNDI2NzAyMDg2fQ.eyJpZCI6MTc3fQ.yBwLFez2RnxTojLniL8YLItWVvBb90HF_yfhcsyg3lY" -H    

"Content-Type:application/multipart/form-data" -d '{"user data":  {"preferred_city":"Newyork","within_radious":"5"}}' --data-binary   

"uploaded_documents":@mydocument.pdf http://127.0.0.1:5000/api/city

现在,我需要在flask请求object.i中读取这个多部分数据

 request.data

它确实打印了数据,但我不知道如何读取流对象并将文件存储到磁盘.

Answer 1

你的curl命令有一些问题,所有这些都可能导致问题:

1. application/multipart/form-data不是有效的MIME类型,因此 Content-Type无效.对于文件上传,内容类型通常是multipart/form-data.此外,您不需要指定内容类型,curl将根据参数进行处理.
2. 使用-F而不是-d将导致curl生成并发布multipart/form-data具有有效边界的 表单.
3. 应为每个表单字段指定名称.

将它们放在一起会产生这个curl命令:

curl -i -H "Authorization":"eyJhbGciOiJIUzI1NiIsImV4cCI6MTQyNjcwNTY4NiwiaWF0IjoxNDI2NzAyMDg2fQ.eyJpZCI6MTc3fQ.yBwLFez2RnxTojLniL8YLItWVvBb90HF_yfhcsyg3lY" \
    -F user_data='{"user data": {"preferred_city":"Newyork","within_radious":"5"}}' \
    -F uploaded_documents=@mydocument.pdf \
    http://127.0.0.1:5000/api/city

如果您不喜欢curl选择的内容类型(文件将是application/octet-stream),您可以为每个部分指定内容类型:

curl -i -H "Authorization":"eyJhbGciOiJIUzI1NiIsImV4cCI6MTQyNjcwNTY4NiwiaWF0IjoxNDI2NzAyMDg2fQ.eyJpZCI6MTc3fQ.yBwLFez2RnxTojLniL8YLItWVvBb90HF_yfhcsyg3lY" \
    -F 'user_data={"user data": {"preferred_city":"Newyork","within_radious":"5"}};type=application/json' \
    -F 'uploaded_documents=@mydocument.pdf;type=application/pdf' \
    http://127.0.0.1:5000/api/city

最后一个命令会生成如下的HTTP请求:

POST /api/city HTTP/1.1
User-Agent: curl/7.32.0
Host: 127.0.0.1:5000
Accept: */*
Authorization:eyJhbGciOiJIUzI1NiIsImV4cCI6MTQyNjcwNTY4NiwiaWF0IjoxNDI2NzAyMDg2fQ.eyJpZCI6MTc3fQ.yBwLFez2RnxTojLniL8YLItWVvBb90HF_yfhcsyg3lY
Content-Length: 496
Expect: 100-continue
Content-Type: multipart/form-data; boundary=------------------------1ab997efff76fe66

--------------------------1ab997efff76fe66
Content-Disposition: form-data; name="user_data"
Content-Type: application/json

{"user data": {"preferred_city":"Newyork","within_radious":"5"}}
--------------------------1ab997efff76fe66
Content-Disposition: form-data; name="uploaded_documents"; filename="mydocument.pdf"
Content-Type: application/pdf

this is the mydocument.pdf file.
it should be a pdf file, but this is easier to test with.

--------------------------1ab997efff76fe66--

然后在Flask中,您可以使用request.form例如访问表单数据request.form['user_data'].因为它是一个json字符串,你可以使用它加载它json.loads(request.form['user_data']).

可以使用Flask文档中的此处和此处request.file描述的方式访问上载的文件.