def get_headers(params, boundary):
"""Returns a dictionary with Content-Type and Content-Length headers
for the multipart/form-data encoding of ``params``."""
headers = {}
boundary = urllib.quote_plus(boundary)
headers['Content-Type'] = "multipart/form-data; boundary=%s" % boundary
headers['Content-Length'] = str(get_body_size(params, boundary))
return headers
def encode_and_quote(data):
"""If ``data`` is unicode, return urllib.quote_plus(data.encode("utf-8"))
otherwise return urllib.quote_plus(data)"""
if data is None:
return None
if isinstance(data, unicode):
data = data.encode("utf-8")
return urllib.quote_plus(data)
def multipart_encode(params, boundary=None, cb=None):
"""Encode ``params`` as multipart/form-data.
``params`` should be a sequence of (name, value) pairs or MultipartParam
objects, or a mapping of names to values.
Values are either strings parameter values, or file-like objects to use as
the parameter value. The file-like objects must support .read() and either
.fileno() or both .seek() and .tell().
If ``boundary`` is set, then it as used as the MIME boundary. Otherwise
a randomly generated boundary will be used. In either case, if the
boundary string appears in the parameter values a ValueError will be
raised.
If ``cb`` is set, it should be a callback which will get called as blocks
of data are encoded. It will be called with (param, current, total),
indicating the current parameter being encoded, the current amount encoded,
and the total amount to encode.
Returns a tuple of `datagen`, `headers`, where `datagen` is a
generator that will yield blocks of data that make up the encoded
parameters, and `headers` is a dictionary with the associated
Content-Type and Content-Length headers.
Examples:
>>> datagen, headers = multipart_encode( [("key", "value1"), ("key", "value2")] )
>>> s = "".join(datagen)
>>> assert "value2" in s and "value1" in s
>>> p = MultipartParam("key", "value2")
>>> datagen, headers = multipart_encode( [("key", "value1"), p] )
>>> s = "".join(datagen)
>>> assert "value2" in s and "value1" in s
>>> datagen, headers = multipart_encode( {"key": "value1"} )
>>> s = "".join(datagen)
>>> assert "value2" not in s and "value1" in s
"""
if boundary is None:
boundary = gen_boundary()
else:
boundary = urllib.quote_plus(boundary)
headers = get_headers(params, boundary)
params = MultipartParam.from_params(params)
return multipart_yielder(params, boundary, cb), headers