HTTP Post Headers not arriving in nifi

Question

I'm quite new to NiFi.

I am sending an HTTP post containing a file and some headers to Nifi, using Python:

 headers = {
     "filename": "Filename",
     "response_url": "https://...",
     "file_id": "123"}

 requests.post(NIFI_URL, files={file.filename: file}, headers=headers, verify=SSA_CA_BUNDLE)

I receive that HTTP post using a Nifi ListenHTTP processor:

The HTTP post appears in Nifi and I can use the file sent there, but I cannot get those HTTP headers into Nifi Attributes.

I could use the red circled attribute to tell Nifi to take those headers and make them attributes of my FlowFile, but it doesn't work.

What am I doing wrong?

Answer 1

import requests

headers = {
     "filename": "Filename",
     "response_url": "https://...",
     "file_id": "123"}

#the required first parameter of the 'get' method is the 'url':
x = requests.post('http://httpbin.org/post', json={'somekey': 'somevalue'}, headers=headers)

#print the response text (the content of the requested file):
print(x.text)

this will print headers python sending to server:

{
  "args": {},
  "data": "{\"somekey\": \"somevalue\"}",
  "files": {},
  "form": {},
  "headers": {
    "Accept": "*/*",
    "Accept-Encoding": "gzip, deflate",
    "Content-Length": "24",
    "Content-Type": "application/json",
    "File-Id": "123",
    "Filename": "Filename",
    "Host": "httpbin.org",
    "Response-Url": "https://...",
    "User-Agent": "python-requests/2.30.0",
    "X-Amzn-Trace-Id": "Root=1-64643b3b-6f4a6aeb063667ef04d7de5e"
  },
  "json": {
    "somekey": "somevalue"
  },
  "origin": "24.218.141.179",
  "url": "http://httpbin.org/post"
}

seems python "normalizing" headers:

"filename"      ==>  "Filename"
"response_url"  ==>  "Response-Url"
"file_id"       ==>  "File-Id"

try to change regex to (?i)filename|response-url|file-id

(?i) == case insensitive for java regex