Seed length issue in signing key

[chirag-jn]

I am referring the following document for completing the onboarding of NP
https://github.com/ONDC-Official/developer-docs/blob/main/registry/Onboarding%20of%20Participants.md
Please note that my subscriber ID is whitelisted.

For completing the onboarding, I am using the python based on-subscribe service as provided here.
I completed the blanks in BAP and BPP dictionaries to complete the information about my organisation.

For getting the signing and encryption key pairs, I used the cryptic_utils.py utility as provided here.

I am making the following POST request (keys hidden):

curl --location 'https://server-with-on-subscribe-service.com/subscribe' \
--header 'Content-Type: application/json' \
--data '{
    "server-with-on-subscribe-service.com | 41c42b3f-91b2-48d3-9de0-19470676578d": {
        "signingPublicKey": "...",
        "signingPrivateKey":"...",
        "ondcPublicKey": "...",
        "encPublicKey": "...",
        "encPrivateKey": "...",
        "type": "BAP",
        "city": "std:011"
    }
}'

The POST request returns

{
    "success": "ACK"
}

However, if I look at the journalctl logs for the application, I see the following error:

[06/Jan/2024 21:25:31] "POST /subscribe HTTP/1.1" 200 -
    self._target(*self._args, **self._kwargs)
  File "/home/ubuntu/apps/on_subscribe_listener/app.py", line 247, in subscribe_helper
    createHtml(REQUEST_ID, subscriber, subscriber_id)
  File "/home/ubuntu/apps/on_subscribe_listener/app.py", line 159, in createHtml
    signature = sign(request_id, subscriber['signingPrivateKey'])
  File "/home/ubuntu/apps/on_subscribe_listener/app.py", line 138, in sign
    signer = SigningKey(signing_private_key64, encoder=nacl.encoding.RawEncoder)
  File "/home/ubuntu/apps/on_subscribe_listener/venv/lib/python3.10/site-packages/nacl/signing.py", line 183, in __init__
    raise exc.ValueError(
nacl.exceptions.ValueError: The seed must be exactly 32 bytes long

Any clue where I might be going wrong?