Cannot get `NanopubClient.find_retractions_of()` to work

[anatoly-scherbakov]

It would seem none of the available Nanopub servers is willing to respond to this request. Here's my test code:

from nanopub import NanopubClient
from nanopub.definitions import NANOPUB_SERVER_LIST

url = 'https://purl.org/np/RARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0'

for use_server in NANOPUB_SERVER_LIST:
    client = NanopubClient(
        use_server=use_server,
    )
    client.grlc_urls = [use_server]

    try:
        retractions = client.find_retractions_of(url)
    except Exception as err:
        print(f'🔴 {use_server} → {err}')
    else:
        print(f'🟢 {use_server} → {retractions}')

Let's try it out.

$ python find_nanopub_server_for_retracted_pubs.py 

⇒

🔴 https://np.petapico.org/ → 400 Client Error:  for url: https://np.knowledgepixels.com/find_signed_nanopubs_with_pattern?pred=http%3A%2F%2Fpurl.org%2Fnanopub%2Fx%2Fretracts&obj=https%3A%2F%2Fpurl.org%2Fnp%2FRARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0&pubkey=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCwUtewGCpT5vIfXYE1bmf%2FUqu1ojqnWdYxv%2BySO80ul8Gu7m8KoyPAwuvaPj0lvPtHrg000qMmkxzKhYknEjq8v7EerxZNYp5B3%2F3%2B5ZpuWOYAs78UnQVjbHSmDdmryr4D4VvvNIiUmd0yxci47dTFUj4DvfHnGd6hVe5%2BgoqdcwIDAQAB&page=1
🔴 http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-1/ → 500 Server Error: Internal Server Error for url: http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-1/find_signed_nanopubs_with_pattern?pred=http%3A%2F%2Fpurl.org%2Fnanopub%2Fx%2Fretracts&obj=https%3A%2F%2Fpurl.org%2Fnp%2FRARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0&pubkey=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCwUtewGCpT5vIfXYE1bmf%2FUqu1ojqnWdYxv%2BySO80ul8Gu7m8KoyPAwuvaPj0lvPtHrg000qMmkxzKhYknEjq8v7EerxZNYp5B3%2F3%2B5ZpuWOYAs78UnQVjbHSmDdmryr4D4VvvNIiUmd0yxci47dTFUj4DvfHnGd6hVe5%2BgoqdcwIDAQAB&page=1
🔴 http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-2/ → 500 Server Error: Internal Server Error for url: http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-2/find_signed_nanopubs_with_pattern?pred=http%3A%2F%2Fpurl.org%2Fnanopub%2Fx%2Fretracts&obj=https%3A%2F%2Fpurl.org%2Fnp%2FRARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0&pubkey=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCwUtewGCpT5vIfXYE1bmf%2FUqu1ojqnWdYxv%2BySO80ul8Gu7m8KoyPAwuvaPj0lvPtHrg000qMmkxzKhYknEjq8v7EerxZNYp5B3%2F3%2B5ZpuWOYAs78UnQVjbHSmDdmryr4D4VvvNIiUmd0yxci47dTFUj4DvfHnGd6hVe5%2BgoqdcwIDAQAB&page=1
🔴 http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-3/ → 500 Server Error: Internal Server Error for url: http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-3/find_signed_nanopubs_with_pattern?pred=http%3A%2F%2Fpurl.org%2Fnanopub%2Fx%2Fretracts&obj=https%3A%2F%2Fpurl.org%2Fnp%2FRARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0&pubkey=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCwUtewGCpT5vIfXYE1bmf%2FUqu1ojqnWdYxv%2BySO80ul8Gu7m8KoyPAwuvaPj0lvPtHrg000qMmkxzKhYknEjq8v7EerxZNYp5B3%2F3%2B5ZpuWOYAs78UnQVjbHSmDdmryr4D4VvvNIiUmd0yxci47dTFUj4DvfHnGd6hVe5%2BgoqdcwIDAQAB&page=1
🔴 http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-4/ → 500 Server Error: Internal Server Error for url: http://app.tkuhn.eculture.labs.vu.nl/nanopub-server-4/find_signed_nanopubs_with_pattern?pred=http%3A%2F%2Fpurl.org%2Fnanopub%2Fx%2Fretracts&obj=https%3A%2F%2Fpurl.org%2Fnp%2FRARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0&pubkey=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCwUtewGCpT5vIfXYE1bmf%2FUqu1ojqnWdYxv%2BySO80ul8Gu7m8KoyPAwuvaPj0lvPtHrg000qMmkxzKhYknEjq8v7EerxZNYp5B3%2F3%2B5ZpuWOYAs78UnQVjbHSmDdmryr4D4VvvNIiUmd0yxci47dTFUj4DvfHnGd6hVe5%2BgoqdcwIDAQAB&page=1
🔴 http://server.nanopubs.lod.labs.vu.nl/ → 400 Client Error:  for url: http://server.nanopubs.lod.labs.vu.nl/find_signed_nanopubs_with_pattern?pred=http%3A%2F%2Fpurl.org%2Fnanopub%2Fx%2Fretracts&obj=https%3A%2F%2Fpurl.org%2Fnp%2FRARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0&pubkey=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCwUtewGCpT5vIfXYE1bmf%2FUqu1ojqnWdYxv%2BySO80ul8Gu7m8KoyPAwuvaPj0lvPtHrg000qMmkxzKhYknEjq8v7EerxZNYp5B3%2F3%2B5ZpuWOYAs78UnQVjbHSmDdmryr4D4VvvNIiUmd0yxci47dTFUj4DvfHnGd6hVe5%2BgoqdcwIDAQAB&page=1
🔴 http://server.np.dumontierlab.com/ → 400 Client Error:  for url: https://server.np.dumontierlab.com/find_signed_nanopubs_with_pattern?pred=http%3A%2F%2Fpurl.org%2Fnanopub%2Fx%2Fretracts&obj=https%3A%2F%2Fpurl.org%2Fnp%2FRARv1-bZWsdvQs88TDH2trcwNoGF1g5AawE2sPKeh5K_0&pubkey=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCwUtewGCpT5vIfXYE1bmf%2FUqu1ojqnWdYxv%2BySO80ul8Gu7m8KoyPAwuvaPj0lvPtHrg000qMmkxzKhYknEjq8v7EerxZNYp5B3%2F3%2B5ZpuWOYAs78UnQVjbHSmDdmryr4D4VvvNIiUmd0yxci47dTFUj4DvfHnGd6hVe5%2BgoqdcwIDAQAB&page=1

The servers seem to respond with 400 or 500. Perhaps the API had changed? 🤔

Version is the latest from PyPI:

$ pip freeze | grep nanopub
nanopub==2.0.1

[anatoly-scherbakov]

Found a way to make it work

        server = 'http://grlc.nanopubs.lod.labs.vu.nl/api/local/local/'

        client = NanopubClient(
            use_server=server,
        )
        client.grlc_urls = [use_server]

Works like this, rewriting grlc_urls is required (timing out otherwise) but would still like to find out what the deep reason is.