Also prefix stored procedures names `raft_join` and `raft_interact`

When instance runs `postjoin` function, it's supposed to have both
target and current grade Offline. Taking a read barrier in that state
makes no sence. Instead, an instance should set target grade online
asap. Ensuring it syncs is the responsibility of the governor.

Excessive read barrier affects `restart_both` test. One of the instances
(i1 who becomes a follower) sends a `read_index` request to i2 (leader).
But i2 reveals  `self.commit_to_current_term()` condition isn't met and
drops the request. As a result, i1 is obliged to wait for 10s timeout
before retrying `read_index` request again, but the test timeouts even
sooner.

Yaroslav Dynnikov authored 2 years ago and Yaroslav Dynnikov committed 2 years ago

Eliminate code duplication, use `define_str_enum` macro from tarantool-module.
Remove personalized `FromStr::Err` for every enum defined that way.

Yaroslav Dynnikov authored 2 years ago and Yaroslav Dynnikov committed 2 years ago

Retain it in tests only

Georgy Moshkin authored 2 years ago and Yaroslav Dynnikov committed 2 years ago

Tarantool synchronous replication is broken in such a way, that local
& asynchronous transactions get rolled back upon synchronous
transaction rollback. This is critical for us, because we use local
spaces for the raft log, which should be orthogonal to synchronous
business spaces, but is not due to this behavior. Until it is fixed, we
will not use synchronous replication.

See https://github.com/tarantool/tarantool/issues/7903

Rewrite it from scratch to satisfy tests and to represent governor
logics in general.

No assumptions should be made on `traft::node::Status.leader_id`. It can
be set to `None` at any time due to a re-election.

Lots of tests are marked "fixme" with the desired value commented.
They'll be fixed in the next commit.