openark/orchestrator: go/logic/snapshot_data.go; 6 LoC

Found a possible issue in [openark/orchestrator](https://www.github.com/openark/orchestrator) at [go/logic/snapshot_data.go](https://github.com/openark/orchestrator/blob/41fdb4756dfc15ef99d3ef6ee21be8335eae5528/go/logic/snapshot_data.go#L157-L162)

Below is the message reported by the analyzer for this snippet of code. Beware that the analyzer only reports the first
issue it finds, so please do not limit your consideration to the contents of the below message.

> function call which takes a reference to existingKey at line 159 may start a goroutine

[Click here to see the code in its original context.](https://github.com/openark/orchestrator/blob/41fdb4756dfc15ef99d3ef6ee21be8335eae5528/go/logic/snapshot_data.go#L157-L162)

Click here to show the 6 line(s) of Go which triggered the analyzer.

```go
for _, existingKey := range existingKeys {
if !snapshotInstanceKeyMap.HasKey(existingKey) {
inst.ForgetInstance(&existingKey)
discardedKeys++
}
}

```

Click here to show extra information the analyzer produced.

```
The following paths through the callgraph could lead to a goroutine:
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (run, 0) -> (runLeader, 0) -> (leaderLoop, 0) -> (checkLeaderLease, 0) -> (pipelineReplicate, 1) -> (pipelineSend, 4) -> (AppendEntries, 2)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (NewNetworkTransportWithLogger, 4) -> (listen, 0) -> (handleConn, 1) -> (handleCommand, 3)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (CreateOrReturnCollection, 1)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Next, 0) -> (Fatalf, 3) -> (runLeader, 0) -> (leaderLoop, 0) -> (goFunc, 1)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (restoreSnapshot, 0) -> (setLastSnapshot, 2)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (NewNetworkTransport, 4) -> (NewNetworkTransportWithLogger, 4) -> (listen, 0)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (WithDeadline, 2) -> (cancel, 2) -> (removeChild, 2)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (GetClusterName, 1) -> (GetString, 1) -> (openDB, 0) -> (Infof, 2) -> (ToSqlite3Insert, 1)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (goFunc, 1)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (startWatcher, 0)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (run, 0) -> (runLeader, 0) -> (leaderLoop, 0) -> (checkLeaderLease, 0) -> (WaitEventChan, 2)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (GetClusterName, 1) -> (GetString, 1) -> (QueryRowsMap, 4) -> (ScanRowsToMaps, 2) -> (on_row, 1)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (Restore, 1)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (NewNetworkTransport, 4) -> (NewNetworkTransportWithLogger, 4) -> (listen, 0) -> (handleConn, 1) -> (handleCommand, 3)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (initializeInstanceDao, 0)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Next, 0) -> (Fatalf, 3) -> (runLeader, 0) -> (leaderLoop, 0) -> (init, 0) -> (newSeed, 0)
(ForgetInstance, 1) -> (AuditOperation, 3)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (newCacheWithJanitor, 3) -> (runJanitor, 2)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Set, 2) -> (string, 1) -> (Exit, 1)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (openDB, 0) -> (Infof, 2) -> (ToSqlite3Insert, 1)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (run, 0) -> (runLeader, 0) -> (leaderLoop, 0) -> (checkLeaderLease, 0) -> (initializeInstanceDao, 0)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (NewNetworkTransport, 4) -> (NewNetworkTransportWithLogger, 4)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (init, 0) -> (newSeed, 0)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (Exec, 1) -> (exec, 2)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (GetClusterName, 1) -> (GetString, 1) -> (OpenOrchestrator, 0) -> (Infof, 5) -> (ExecOrchestrator, 1)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (run, 0) -> (runLeader, 0) -> (leaderLoop, 0) -> (checkLeaderLease, 0)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Next, 0) -> (Fatalf, 3) -> (runLeader, 0) -> (leaderLoop, 0) -> (init, 0)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (run, 0) -> (runLeader, 0) -> (leaderLoop, 0) -> (checkLeaderLease, 0) -> (MarkConfigurationLoaded, 0)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Next, 0) -> (Fatalf, 3) -> (runLeader, 0) -> (leaderLoop, 0) -> (replicate, 1) -> (pipelineReplicate, 1) -> (pipelineSend, 4) -> (AppendEntries, 2)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (MarkConfigurationLoaded, 0)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (WithDeadline, 2) -> (cancel, 2)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (WithTimeout, 2) -> (WithDeadline, 2) -> (cancel, 2)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (restoreSnapshot, 0) -> (setLastSnapshot, 2) -> (NewDecoder, 2) -> (newDecDriver, 1) -> (ExecOrchestrator, 2) -> (mkInsertOdku, 5) -> (ToJSON, 0)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (New, 2) -> (newCacheWithJanitor, 3) -> (runJanitor, 2)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (NewNetworkTransportWithLogger, 4)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (New, 2)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Read, 1) -> (decode, 1) -> (decMapInt64Intf, 1) -> (readMapLen, 0) -> (init, 0)
(ForgetInstance, 1) -> (Errorf, 2) -> (logFormattedEntry, 3) -> (Debug, 1) -> (Next, 0) -> (Fatalf, 3) -> (runLeader, 0) -> (leaderLoop, 0) -> (GetInState, 1) -> (Printf, 8)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (NewNetworkTransportWithLogger, 4) -> (listen, 0)
(ForgetInstance, 1) -> (AuditOperation, 3) -> (, 0) -> (AddVals, 1) -> (read, 1) -> (Fatale, 1) -> (Exit, 1) -> (readInto, 4) -> (Restore, 1) -> (NewDecoder, 2) -> (getBasicHandle, 0) -> (ExecOrchestrator, 2) -> (mkInsertOdku, 5) -> (ToJSON, 0)

```

Leave a reaction on this issue to contribute to the project by classifying this instance as a **Bug** :-1:, **Mitigated** :+1:, or **Desirable Behavior** :rocket:
See the descriptions of the classifications [here](https://github.com/github-vet/rangeclosure-findings#how-can-i-help) for more information.

commit ID: 41fdb4756dfc15ef99d3ef6ee21be8335eae5528