Merge pull request #3340 from influxdata/crepererum/set_server_id_twice

fix: allow setting the same server ID twice

influxdb_iox/tests/end_to_end_cases/deployment_api.rs

@@ -129,7 +129,16 @@ async fn assert_set_get_server_id(server_fixture: ServerFixture) {
     let got = client.get_server_id().await.expect("get ID failed");
     assert_eq!(got, Some(test_id));
 
-    // setting server ID a second time should fail
+    // setting server ID to same ID should be OK
+    client
+        .update_server_id(test_id)
+        .await
+        .expect("set ID again failed");
+
+    let got = client.get_server_id().await.expect("get ID failed");
+    assert_eq!(got, Some(test_id));
+
+    // setting server ID to a different ID should fail
     let result = client
         .update_server_id(NonZeroU32::try_from(13).unwrap())
         .await;

server/src/lib.rs

@@ -470,6 +470,15 @@ impl Server {
         let mut state = self.shared.state.write();
         let startup = match &**state {
             ServerState::Startup(startup) => startup.clone(),
+            state
+                if state
+                    .server_id()
+                    .map(|existing| existing == server_id)
+                    .unwrap_or_default() =>
+            {
+                // already set to same ID
+                return Ok(());
+            }
             _ => return Err(Error::IdAlreadySet),
         };
 
@@ -2459,4 +2468,20 @@ mod tests {
             ])
             .unwrap();
     }
+
+    #[tokio::test]
+    async fn set_server_id_twice() {
+        test_helpers::maybe_start_logging();
+        let server = make_server(make_application());
+
+        server.set_id(ServerId::try_from(1).unwrap()).unwrap();
+        server.wait_for_init().await.unwrap();
+
+        server.set_id(ServerId::try_from(1).unwrap()).unwrap();
+
+        assert_error!(
+            server.set_id(ServerId::try_from(2).unwrap()),
+            Error::IdAlreadySet
+        );
+    }
 }