When running getTips on an isolated node an empty array is returned

[GalRogozinski]

Bug description

If you run a node that is not receiving any transactions, the tip cache (TipsViewModel) is not populated. so getTips api call will return an empty array.

Not sure whether the solution is to persist tips, or maybe scan for them upon starting IRI.

IRI version

1.8.1

Steps To Reproduce

1. Run a node in isolation
2. Call getTips:

curl http://localhost:14265 \
-X POST \
-H 'Content-Type: application/json' \
-H 'X-IOTA-API-Version: 1' \
-d '{"command": "getTips"}'

Expected behaviour

List of tips should be retruned

Actual behaviour

An empty list is returned:
"hashes": [],

[muXxer]

Why does it even matter?
If you would persist the tips at shutdown, and spin up your node again... the tips are lazy.

A fullnode has to wait some seconds to receive new tips after startup. Even that makes no sense, because for consensus you need solid tips. So spin up the node and let it sync first.

IMHO the API call "getTips" is an old debug API call. Its just nonsense and confusing. I would remove it and we will not implement it in HORNET.

[jakubcech]

We'll try and figure out if anyone's actually using it for some scenario and if not we can just deprecate it.

[GalRogozinski]

According to Discord we should remove it