bb1a798c2c
This PR solves a series of similar problems related to executing
methods on an already aborted `raft::server`. They materialize
in various ways:
* For `add_entry` and `modify_config`, a `raft::not_a_leader` with
a null ID will be returned IF forwarding is disabled. This wasn't
a big problem because forwarding has always been enabled for group0,
but it's something that's nice to fix. It's might be relevant for
strong consistency that will heavily rely on this code.
* For `wait_for_leader` and `wait_for_state_change`, the calls may
hang and never resolve. A more detailed scenario is provided in a
commit message.
For the last two methods, we also extend their descriptions to indicate
the new possible exception type, `raft::stopped_error`. This change is
correct since either we enter the functions and throw the exception
immediately (if the server has already been aborted), or it will be
thrown upon the call to `raft::server::abort`.
We fix both issues. A few reproducer tests have been included to verify
that the calls finish and throw the appropriate errors.
Fixes SCYLLADB-841
Backport: Although the hanging problems haven't been spotted so far
(at least to the best of my knowledge), it's best to avoid
running into a problem like that, so let's backport the
changes to all supported versions. They're small enough.
Closes scylladb/scylladb#28822
* https://github.com/scylladb/scylladb:
raft: Make methods throw stopped_error if server aborted
raft: Throw stopped_error if server aborted
test: raft: Introduce get_default_cluster
Running tests with pytest
To run test with pytest execute
pytest test/raft
To execute only one file, provide the path filename
pytest test/raft/many_test.cc
Since it's a normal path, autocompletion works in the terminal out of the box.
To provide a specific mode, use the next parameter --mode dev,
if parameter isn't provided pytest tries to use ninja mode_list to find out the compiled modes.
Parallel execution is controlled by pytest-xdist and the parameter -n auto.
This command starts tests with the number of workers equal to CPU cores.