adds latest flag to get timestamps when roots expire

[akhileshh]

#499

[ceesem]

Hm, I'm not sure if this is working.

I added a latest and timestamp parameter to a caveclient branch and am getting the following error:

from caveclient import CAVEclient, chunkedgraph

cmain = CAVEclient('minnie65_phase3_v1')

ltv5_server_address = "https://ltv5.microns-daf.com"
pcg_client = chunkedgraph.ChunkedGraphClient(
    server_address=ltv5_server_address,
    auth_client=cmain.auth,
    table_name=cmain.chunkedgraph.table_name
)

pcg_client.get_root_timestamps([864691135565770007, 864691135837393555], latest=True)

responds with

500 Server Error: pop from an empty deque for url: https://ltv5.microns-daf.com/segmentation/api/v1/table/minnie3_v1/root_timestamps?latest=True

Traceback (most recent call last):

  File "/app/venv/lib/python3.11/site-packages/flask/app.py", line 1484, in full_dispatch_request
    rv = self.dispatch_request()
     ^

  File "/app/venv/lib/python3.11/site-packages/flask/app.py", line 1469, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)
                                                                        ^

  File "/app/venv/lib/python3.11/site-packages/middle_auth_client/decorators.py", line 296, in decorated_function
    return f(*args, **kwargs)
     ^

  File "/app/venv/lib/python3.11/site-packages/middle_auth_client/decorators.py", line 418, in decorated_function
    return f(*args, **kwargs)
     ^

  File "/app/pychunkedgraph/app/app_utils.py", line 50, in decorated_function
    return f(*args, **kwargs)
     ^

  File "/app/pychunkedgraph/app/segmentation/v1/routes.py", line 537, in handle_root_timestamps
    root_timestamps = common.handle_root_timestamps(
                                                   ^

  File "/app/pychunkedgraph/app/segmentation/common.py", line 1101, in handle_root_timestamps
    result.append(new_roots_ts.popleft())
                   ^

IndexError: pop from an empty deque

The same thing works as expected with latest=False.

[fcollman]

I think this doesn't error nicely if you pass a latest=True and a timestamp that is before when the root_id was created. Also we should have a PCG 1.0 version of this PR.