This is a port of this PR: #2235
(But it was easier to copy-paste than rebase, given the split of umap.js
and co.)
Co-authored-by: Alexis Métaireau <alexis@notmyidea.org>
Co-authored-by: David Larlet <david@larlet.fr>
- Operations are now stored locally in memory. All operations are tied
to an HLC (Hybrid Logical Clock), making it possible to order them
concistently.
- Messages are handled in their `on*` methods, leading to a clearer
implementation.
- When a new peer joins, it asks a random peer for the list of
operations, and re-apply them locally.
- Messages types names have been updated to follow CamelCase, and to be
similar across the client and the server.
- Pass `sync=False` to `makeFeature` in the updaters, to avoid
generating duplicate operations on message retrieval.
Using [pytest-xprocess](https://pytest-xprocess.readthedocs.io/) proved
not being as useful as I thought at first, because it was causing
intermitent failures when starting the process.
The code now directly uses `subprocess.popen` calls to start the server.
The tests are grouped together using the following decorator:
`@pytest.mark.xdist_group(name="websockets")`
Tests now need to be run with the `pytest --dist loadgroup` so that all
tests of the same group happen on the same process.
More details on this blogpost:
https://blog.notmyidea.org/start-a-process-when-using-pytest-xdist.html
