# Description of change

After a validator node leaves the committee, a few resources in
validator components are leaked including metrics and grpc server. If
the node will try to re-join the committee it will crash due to
resources already being in use.

This PR:
- changes the way validator metrics are registered: a dedicated registry
is used instead of default one;
- adds a graceful shutdown of validator grpc server and metrics registry
clean up during reconfiguration when a validator leaves the committee;
- adds a reproducer test.

## Notes

There are a few ways to handle metrics issue:
- ignore `AlreadyReg` error while trying to re-register metrics with the
default registry; requires special unwrap handling for each metric;
- unregister individual metrics with the default registry; the existing
components do not provide such functionality; requires unregistering all
individual metrics;
- use a dedicated registry and remove it entirely from the registry
service once node is not validator anymore; this seems to be the easiest
and cleanest way.

:warning: There may be other undetected resources leaking that do not
cause error if validator components are re-created.

## Links to any relevant issues

Fixes #6277.

## Type of change

- Bug fix (a non-breaking change which fixes an issue)

## How the change has been tested

```sh
scripts/simtest/cargo-simtest simtest --package iota-e2e-tests --test "reconfiguration_tests" --profile ci -- test_reconfig_with_same_validator
```

## Change checklist

- [x] I have followed the contribution guidelines for this project
- [x] I have performed a self-review of my own code
- [x] I have commented my code, particularly in hard-to-understand areas
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] I have checked that new and existing unit tests pass locally with
my changes

### Release Notes

- [ ] Protocol:
- [x] Nodes (Validators and Full nodes): Fixed a bug causing iota-node
to crash after re-joining the consensus committee as validator.
- [ ] Indexer:
- [ ] JSON-RPC:
- [ ] GraphQL:
- [ ] CLI:
- [ ] Rust SDK:
- [ ] REST API:

---------

Co-authored-by: muXxer <[email protected]>

…onents (#6831) (#7093)

# Description of change

After a validator node leaves the committee, a few resources in
validator components are leaked including metrics and grpc server. If
the node will try to re-join the committee it will crash due to
resources already being in use.

This PR:
- changes the way validator metrics are registered: a dedicated registry
is used instead of default one;
- adds a graceful shutdown of validator grpc server and metrics registry
clean up during reconfiguration when a validator leaves the committee;
- adds a reproducer test.

## Notes

There are a few ways to handle metrics issue:
- ignore `AlreadyReg` error while trying to re-register metrics with the
default registry; requires special unwrap handling for each metric;
- unregister individual metrics with the default registry; the existing
components do not provide such functionality; requires unregistering all
individual metrics;
- use a dedicated registry and remove it entirely from the registry
service once node is not validator anymore; this seems to be the easiest
and cleanest way.

:warning: There may be other undetected resources leaking that do not
cause error if validator components are re-created.

## Links to any relevant issues

Fixes #6277.

## Type of change

- Bug fix (a non-breaking change which fixes an issue)

## How the change has been tested

```sh
scripts/simtest/cargo-simtest simtest --package iota-e2e-tests --test "reconfiguration_tests" --profile ci -- test_reconfig_with_same_validator
```

## Change checklist

- [x] I have followed the contribution guidelines for this project
- [x] I have performed a self-review of my own code
- [x] I have commented my code, particularly in hard-to-understand areas
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] I have checked that new and existing unit tests pass locally with
my changes

### Release Notes

- [ ] Protocol:
- [x] Nodes (Validators and Full nodes): Fixed a bug causing iota-node
to crash after re-joining the consensus committee as validator.
- [ ] Indexer:
- [ ] JSON-RPC:
- [ ] GraphQL:
- [ ] CLI:
- [ ] Rust SDK:
- [ ] REST API:

Co-authored-by: muXxer <[email protected]>