fix: panic Storage::active_learners when peer was rebootstrapped

src/traft/storage.rs

@@ -7,6 +7,7 @@ use ::raft::INVALID_ID;
 use ::tarantool::index::IteratorType;
 use ::tarantool::space::Space;
 use ::tarantool::tuple::Tuple;
+use ::tarantool::unwrap_or;
 use serde::de::DeserializeOwned;
 use serde::Serialize;
 use thiserror::Error;
@@ -28,8 +29,6 @@ enum Error {
     NoSuchSpace(String),
     #[error("no such index \"{1}\" in space \"{0}\"")]
     NoSuchIndex(String, String),
-    #[error("no peer with id {0}")]
-    NoSuchPeer(RaftId),
 }
 
 macro_rules! box_err {
@@ -361,11 +360,7 @@ impl Storage {
         let learners = Storage::learners()?;
         let mut res = Vec::with_capacity(learners.len());
         for raft_id in learners {
-            if Storage::peer_by_raft_id(raft_id)?
-                .ok_or(Error::NoSuchPeer(raft_id))
-                .map_err(box_err!())?
-                .is_active()
-            {
+            if unwrap_or!(Storage::peer_by_raft_id(raft_id)?, continue).is_active() {
                 res.push(raft_id)
             }
         }

test/conftest.py

@@ -235,11 +235,11 @@ class Instance:
             eprint(f"{self} killed")
         self.process = None
 
-    def terminate(self, kill_after_seconds=10):
+    def terminate(self, kill_after_seconds=10) -> int | None:
         """Terminate the instance gracefully with SIGTERM"""
         if self.process is None:
             # Be idempotent
-            return
+            return None
 
         with suppress(ProcessLookupError, PermissionError):
             os.killpg(self.process.pid, signal.SIGCONT)
@@ -247,8 +247,9 @@ class Instance:
         self.process.terminate()
 
         try:
-            self.process.wait(timeout=kill_after_seconds)
-            eprint(f"{self} terminated")
+            rc = self.process.wait(timeout=kill_after_seconds)
+            eprint(f"{self} terminated: rc = {rc}")
+            return rc
         finally:
             self.kill()
 

test/int/test_joining.py

@@ -237,6 +237,9 @@ def test_rebootstrap_follower(cluster3: Cluster):
     i3.wait_ready()
     i3.assert_raft_status("Follower")
 
+    # git.picodata.io: #114
+    assert i1.terminate() == 0
+
 
 def test_join_without_explicit_instance_id(cluster: Cluster):
     # Scenario: bootstrap single instance without explicitly given instance id