How to send multipart/form-data for image binary with Python requests lib (with CRLF chars)? - file-upload

Question

I'm trying to upload a local image to the Medium /images endpoint (documented here).
Their example request looks like:
Host: api.medium.com
Authorization: Bearer 181d415f34379af07b2c11d144dfbe35d
Content-Type: multipart/form-data; boundary=FormBoundaryXYZ
Accept: application/json
Accept-Charset: utf-8
--FormBoundaryXYZ
Content-Disposition: form-data; name="image"; filename="filename.png"
Content-Type: image/png
IMAGE_DATA
--FormBoundaryXYZ--
The type of image data is never specified, but I'm assuming it's raw binary based on this very similar API call from Ancestry for uploading images.
Currently, I have:
headers['Content-Type'] = 'multipart/form-data; boundary=FormBoundaryXYZ'
imageData = '''--FormBoundaryXYZ
Content-Disposition: form-data; name="image"; filename="filename.jpg"
Content-Type: image/jpeg
0000000000000011111111111111111111111111
0000000000000011111111111111111111111111
0000000000000011111111111111111111111111
0000000000000000011111111111111111111111
0000000000000000000111111111111111111111
0000000000000000000000000000000000000000
0000000000000000000000000000000000000000
0000000000000000000000000000000000000000
0000000000000000000001000000000000000000
0000000000000000000100000000000000000000
0000000000000000010000000000000000000000
0000000000000000000000000000000000000000
0000000010000000000000000000000000000000
0000000000001100000000000000000000000000
0000000000000100000001000000000000000000
0000000000000000000001000000000000000010
0000000000000000001001111111110000000001
0000000000000000000000100110000000000000
0000000000000000000000000001110000000000
0000000000000000011110001111111101100000
0000000000000000111111111111111111111111
0000000001000001111111111111111111111111
0000000000000011111111111111111111111111
0000000100001011111111111111111111111111
0000001100000001111111111111111111111111
0000110000000000000000000000000000000000
0001000000000000000000000000000000000000
--FormBoundaryXYZ--'''
def post_image(imgData):
req = r.post(base_url+'/images', headers=headers, data=imgData)
res = req.json()
return res
print(json.dumps(post_image(imageData), indent=2))
When executed, I get the error response:
{
"errors": [
{
"message": "Expected CR Received 10",
"code": -1
}
]
}
The documentation mentions
All lines in the body must be terminated with \r\n.
and I know that the "10" in the response must be the "\n", so I'm missing the "\r". I've tried explicitly adding "\r\n" to the end of each line termination, but then I get an error like
{
"errors": [
{
"message": "Expected alphabetic character, received 10",
"code": -1
}
]
}
Or
{
"errors": [
{
"message": "stream ended unexpectedly",
"code": -1
}
]
}
depending on where I place the /r/n or remove it.
My question is: Is there a way to format this that I'm missing or overthinking? I'm hoping I'm just inexperienced in multipart/form-data encoding and I could be doing this programmatically instead.
Thanks! I'd be happy to add details if needed!
(As a side note: I got the image's binary data with the dcode.fr/binary-image tool.)