parse multipart/form-data, received from requests post

Question

I am writing Web Service Client, using requests library. I am getting data in multipart/form-data that contains a file and text-json. I have no idea how to parse it. Is there a proper library to parse multipart/form-data format in python or should I write parser on my own?

my code:

data = {
  "prototypeModel" :('prototypeModel', open(prototypeModel, 'rb'), 'application/octet-stream', {'Expires': '0'}),
  "mfcc_1" : ('mfcc', open(mfcc_1, 'rb'), 'application/octet-stream', {'Expires': '0'}),
  "mfcc_2" : ('mfcc', open(mfcc_2, 'rb'), 'application/octet-stream', {'Expires': '0'}),
  "mfcc_3" : ('mfcc', open(mfcc_3, 'rb'), 'application/octet-stream', {'Expires': '0'}),
}

print( '---------------------- start enroll ----------------------')
testEnrollResponse = requests.post(server+sessionID, files = data, json = declaredParameters)

b'\r\n--c00750d1-8ce4-4d29-8390-b50bf02a92cc\r\nContent-Disposition: form-data; name="playbackHash"\r\nContent-Type: application/octet-stream\r\n\r\n\x16\x00\x00\x00\x00\x00\x00\x00serialization::archive\n\x00\x04\x08\x04 .... x00\x00R\x94\x9bp\x8c\x00\r\n--c00750d1-8ce4-4d29-8390-b50bf02a92cc\r\nContent-Disposition: form-data; name="usersMFCC"\r\nContent-Type: application/octet-stream\r\n\r\n\x16\x00\x00\x00\x00\x00\x00\x00serialization::archive\n\x00\x04\x08\x04\x08\x01\x00\x00\x00\x00\x00\x00\x00\x00\xf8\x16\x00\x00\x00\x00\x00\x00u\xbd\xb4/\xda1\xea\xbf\x0f\xed\xa2<\xc9\xf8\xe7\xbf?\xd5\xf06u\xe7\xf0\xbf\xd4\x8d\xd4\xa1F\xbe\x03@\x85X!\x19\xd8A\x06@\x8co\xf7\r .....
x80\xd9\x95Yxn\xd0?\r\n--c00750d1-8ce4-4d29-8390-b50bf02a92cc\r\nContent-Disposition: form-data; name="scoreAndStatus"\r\nContent-Type: application/json; charset=utf-8\r\n\r\n{"lexLikelihood":1.544479046897232,"overallScore":-nan,"playbackLikelihood":-inf,"status":{"errorCode":0,"errorMessage":""}}\r\n--c00750d1-8ce4-4d29-8390-b50bf02a92cc--\r\n'

I replaced more binary data with " ..... "

Answer 1

If you're receiving a multipart/form-data response, you can parse it using the requests-toolbelt library like so:

$ pip install requests-toolbelt

After installing it

from requests_toolbelt.multipart import decoder

testEnrollResponse = requests.post(...)
multipart_data = decoder.MultipartDecoder.from_response(testEnrollResponse)

for part in multipart_data.parts:
    print(part.content)  # Alternatively, part.text if you want unicode
    print(part.headers)

Answer 2

Code sample for Flask, uses https://github.com/defnull/multipart

import multipart as mp
from multipart import tob

try:
    from io import BytesIO
except ImportError:
    from StringIO import StringIO as BytesIO

@app.route('/', methods=["GET","POST"])
def index():
        ...
        elif flask.request.method == "POST":
                data = flask.request.data
                s = data.split("\r")[0][2:]
                p = mp.MultipartParser(BytesIO(tob(data)),s)
                blob = p.parts()[0].value
                f = open("file.bin","wb")
                f.write(blob.encode("latin-1"))
                f.close()