Creating attachments ignore the attachment id

[jl-wynen]

Summary

Using POST datasets/{dataset_id}/attachments with a payload that includes an id for the attachment ignores the id and assigns a new id.

I tested with backend versions 4.20 and 4.24

Steps to Reproduce

The following scitacean code creates a dataset, uploads an attachment, and then uploads a second attachment with the same id as the first.
The result is that the dataset has 2 attachments with different ids.

from pathlib import Path

from scitacean import PID, Attachment, Client, Dataset
from scitacean.testing import backend

docker_file = Path(__file__).resolve().parent / "backend" / "docker-compose.yaml"
docker_file.parent.mkdir(exist_ok=True)

# uncomment these lines to start a local scicat backend:
# backend.configure(docker_file)
# backend.start_backend(docker_file)
# backend.wait_until_backend_is_live(max_time=20, n_tries=20)

# backend.stop_backend(docker_file)

access = backend.config.local_access("user1")
client = Client.from_credentials(
    url=access.url,
    **access.user.credentials,
)
ds = Dataset(
    type="raw",
    name="test",
    contact_email="asd@qwe.de",
    creation_location="here",
    investigator="me",
    owner=access.user.username,
    owner_group=access.user.group,
    source_folder="/hex/source",
)
finalized = client.upload_new_dataset_now(ds)

datset_pid = PID.parse("PID.prefix.a0b1/c846ee90-2bfd-4263-83a4-93529acbe890")
attachment1 = Attachment(
    caption="test attachment",
    owner_group=access.user.group,
)
finalized = client.scicat.create_attachment_for_dataset(
    attachment1.make_upload_model(), dataset_id=datset_pid
)
attachment_id = finalized.id

attachment2 = Attachment(
    caption="test attachment2",
    owner_group=access.user.group,
    id=attachment_id,
)
client.scicat.create_attachment_for_dataset(
    attachment2.make_upload_model(), dataset_id=datset_pid
)

downloaded = client.scicat.get_attachments_for_dataset(datset_pid)
print(downloaded)

ds = client.get_dataset(datset_pid, attachments=True)
print(ds.attachments)

Current Behaviour

The id field seems to be ignore.

Expected Behaviour

Either

• Use the id for the attachment. If there already is an attachment with that id, fail.
• Forbid passing an id in upload and don't silently ignore it.