Progress of Python requests post

Question

I am uploading a large file using the Python requests package, and I can't find any way to give data back about the progress of the upload. I have seen a number of progress meters for downloading a file, but these will not work for a file upload.

The ideal solution would be some sort of callback method such as:

def progress(percent):
  print percent
r = requests.post(URL, files={'f':hugeFileHandle}, callback=progress)

Thanks in advance for your help :)

Answer 1

requests doesn't support upload streaming e.g.:

import os
import sys
import requests  # pip install requests

class upload_in_chunks(object):
    def __init__(self, filename, chunksize=1 << 13):
        self.filename = filename
        self.chunksize = chunksize
        self.totalsize = os.path.getsize(filename)
        self.readsofar = 0

    def __iter__(self):
        with open(self.filename, 'rb') as file:
            while True:
                data = file.read(self.chunksize)
                if not data:
                    sys.stderr.write("\n")
                    break
                self.readsofar += len(data)
                percent = self.readsofar * 1e2 / self.totalsize
                sys.stderr.write("\r{percent:3.0f}%".format(percent=percent))
                yield data

    def __len__(self):
        return self.totalsize

# XXX fails
r = requests.post("http://httpbin.org/post",
                  data=upload_in_chunks(__file__, chunksize=10))

^{btw, if you don't need to report progress; you could use memory-mapped file to upload large file.}

To workaround it, you could create a file adaptor similar to the one from urllib2 POST progress monitoring:

class IterableToFileAdapter(object):
    def __init__(self, iterable):
        self.iterator = iter(iterable)
        self.length = len(iterable)

    def read(self, size=-1): # TBD: add buffer for `len(data) > size` case
        return next(self.iterator, b'')

    def __len__(self):
        return self.length

Example

it = upload_in_chunks(__file__, 10)
r = requests.post("http://httpbin.org/post", data=IterableToFileAdapter(it))

# pretty print
import json
json.dump(r.json, sys.stdout, indent=4, ensure_ascii=False)

Answer 2

I recommend to use a tool package named requests-toolbelt, which make monitoring upload bytes very easy, like

from requests_toolbelt import MultipartEncoder, MultipartEncoderMonitor
import requests

def my_callback(monitor):
    # Your callback function
    print monitor.bytes_read

e = MultipartEncoder(
    fields={'field0': 'value', 'field1': 'value',
            'field2': ('filename', open('file.py', 'rb'), 'text/plain')}
    )
m = MultipartEncoderMonitor(e, my_callback)

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

And you may want to read this to show a progress bar.