通过HTTP POST传递二进制文件

Question

I have a local python file that decodes binary files. This python file first reads from the file, opens it as binary and then saves it in a buffer and interprets it. Reading it is simply:

with open(filepath, 'rb') as f:
    buff = f.read()
read_all(buff)

This works fine locally. Now I'd like to setup a Azure Python job where I can send the file, approx. 100kb, over a HTTP POST and then read the interpreted meta data which my original python script does well.

I've first removed the read function so that I'll now work with the buffer only. In my Azure Python Job I have the following, triggered by a HttpRequest

my_data = reader.read_file(req.get_body())

To test my sending I've tried the following in python

import requests

url = 'http://localhost:7071/api/HttpTrigger'
files = {'file': open('test', 'rb')}
with open('test', 'rb') as f:
        buff = f.read()

r = requests.post(url, files=files) #Try using files
r = requests.post(url, data=buff) #Try using data

I've also tried in Postman adding the file to the body as a binary and setting the headers to application/octet-stream

All this doesn't send the binary file the same way as the original f.read() did. So I'm getting a wrong interpretation of the binary file.

What is file.read doing differently to how I'm sending it over as a HTTP Body message?

Printing out the first line from the local python read file gives.

b'\n\n\xfe\xfe\x00\x00\x00\x00\\\x18,A\x18\x00\x00\x00(\x00\x00\x00\x1f\x00\x00\

Whereas printing it out at the req.get_body() shows me

b'\n\n\xef\xbf\xbd\xef\xbf\xbd\x00\x00\x00\x00\\\x18,A\x18\x00\x00\x00(\x00\x00\x00\x1f\x00\

So something is clearly wrong. Any help why this could be different?

Thanks

EDIT:

I've implemented a similar function in Flask and it works well. The code in flask is simply grabbing the file from a POST. No encoding/decoding.

if request.method == 'POST':
      f = request.files['file']
      #f.save(secure_filename(f.filename))
      my_data = reader.read_file(f.read())

Why is the Azure Function different?

Answer 1

You can try UTF-16 to decode and do the further action in your code.

Here is the code for that:

 with open(path_to_file,'rb') as f: contents = f.read() contents = contents.rstrip("\\n").decode("utf-16") 

Basically after doing re.get_body, perform the below operation:

contents = contents.rstrip("\n").decode("utf-16")

See if it gives you the same output as your receive in local python file.

Hope it helps.