Demo of GCS resumable upload of unknown content size

import requests

url = 'https://www.googleapis.com/upload/storage/v1/b/my-bucket/o?alt=json&name=test-file2&uploadType=resumable'

auth = ('Authorization',
        'Bearer ya29.....g')

resp = requests.post(url, headers=dict([auth, ('X-Upload-Content-Type', 'text/plain')]))
assert resp.status_code == 200

url = resp.headers['location']

# Note using bytes */* in content range
resp = requests.post(url, headers=dict([auth, ('Content-Range', 'bytes */*')]))
assert resp.status_code == 308

# send first full 256K chunk, still without specifying full content length
resp = requests.post(url, headers=dict([auth, ('Content-Range', 'bytes 0-262143/*'), ('Content-Type', 'text/plain')]), data='A' * 262144)
assert resp.status_code == 308

# Just for fun let's ask where we are in the upload. Still not specifying full content length.
resp = requests.post(url, headers=dict([auth, ('Content-Range', 'bytes */*')]))
assert resp.status_code == 308
assert resp.headers['range'] == 'bytes=0-262143'

# upload final chunk of 10 bytes, and specify full content length for the first time
resp = requests.post(url, headers=dict([auth, ('Content-Range', 'bytes 262144-262153/262154'), ('Content-Type', 'text/plain')]), data='A' * 10)
assert resp.status_code == 200
assert resp.json()['size'] == '262154'

print 'Grandi successi!!!'