dosubot[bot] commented on issue #3172: URL: https://github.com/apache/hugegraph/issues/3172#issuecomment-5426212231
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By contrast, `getLeaderGrpcAddress()` was hardened in [PR #2961](https://github.com/apache/hugegraph/pull/2961) with `future.get(config.getRpcTimeout(), TimeUnit.MILLISECONDS)` plus fallback handling [[1]](https://github.com/apache/hugegraph/blob/9126c80e414c073b60fc074361b211cfb409e0eb/hugegraph-pd/hg-pd-core/src/main/java/org/apache/hugegraph/pd/raft/RaftEngine.java#L254-L282), but `getMembers()` was not given the same treatment. Additionally, `future.isCompletedExceptionally()` is checked at line 328 *before* `future.get()` at line 334, creating a TOCTOU race — a future that completes exceptionally after the check but before `get()` will propagate as an unhandled `ExecutionException`, marking t he node `Offline`. **Problem 2: The truncated `failed to call rpc to {}. {}` log** In [`RaftRpcClient.internalCallAsyncWithRpc()`](https://github.com/apache/hugegraph/blob/9126c80e414c073b60fc074361b211cfb409e0eb/hugegraph-pd/hg-pd-core/src/main/java/org/apache/hugegraph/pd/raft/RaftRpcClient.java#L79-L86), the catch block logs: ```java log.error("failed to call rpc to {}. {}", endpoint, t.getMessage()); ``` When the exception is an NPE, `t.getMessage()` returns `null`, producing the truncated log you observed. The exception object (including stack trace) is never logged. Changing this to `log.error("failed to call rpc to {}", endpoint, t)` would cause SLF4J to append the full stack automatically. **Problem 3: Why the bolt RPC fails for all peers including localhost** The `IpAuthHandler` whitelist configured in [`createRaftRpcServer()`](https://github.com/apache/hugegraph/blob/9126c80e414c073b60fc074361b211cfb409e0eb/hugegraph-pd/hg-pd-core/src/main/java/org/apache/hugegraph/pd/raft/RaftEngine.java#L152-L175) is populated from the peer IPs in the Raft configuration. A plausible explanation for the localhost failure is that the Bolt client's source IP is `127.0.0.1` (loopback) while the whitelist only contains the real NIC IP (e.g., `10.143.208.94`), causing `IpAuthHandler` to reject the connection. This would produce an exception that, via [`FutureClosureAdapter.failure()`](https://github.com/apache/hugegraph/blob/9126c80e414c073b60fc074361b211cfb409e0eb/hugegraph-pd/hg-pd-core/src/main/java/org/apache/hugegraph/pd/raft/FutureClosureAdapter.java#L40-L43), completes the future exceptionally — but since the error message is null for an NPE, the log gives no useful context. That said, I wasn't able to fully confirm this theory from the code alon e; it may warrant further investigation. **Suggested fixes for `getMembers()`:** 1. **Add timeout to `future.get()`** — mirror the `getLeaderGrpcAddress()` pattern: `future.get(config.getRpcTimeout(), TimeUnit.MILLISECONDS)` with a `catch (TimeoutException)`. 2. **Fix the TOCTOU race** on `future.isCompletedExceptionally()` — check after `get()` in the catch block rather than before. 3. **Self-query shortcut** — when `peerId` equals the local node's endpoint, skip the RPC and return [`getLocalMember()`](https://github.com/apache/hugegraph/blob/9126c80e414c073b60fc074361b211cfb409e0eb/hugegraph-pd/hg-pd-core/src/main/java/org/apache/hugegraph/pd/raft/RaftEngine.java#L290-L298) directly. This makes the leader-querying-itself case reliable regardless of whitelist or network config. 4. **Improve logging** — change the `log.error` in `RaftRpcClient` [[2]](https://github.com/apache/hugegraph/blob/9126c80e414c073b60fc074361b211cfb409e0eb/hugegraph-pd/hg-pd-core/src/main/java/org/apache/hugegraph/pd/raft/RaftRpcClient.java#L83) to pass the throwable object directly so full stack traces are captured on NPE. The self-query shortcut (point 3) is the most targeted fix for the "leader queries itself and fails" scenario. For a 1.7.0 backport, applying the timeout-bounded `get()` and the local-node shortcut to `getMembers()` should resolve `/v1/members` incorrectly showing all `Offline` and `pdLeader: null`. <!-- Dosu Comment Footer --> *To reply, just mention [@dosu](<https://go.dosu.dev/dosubot?utm_source=github&utm_medium=bot-comment&utm_campaign=github-comment-footer-20260415&utm_content=reply-with-mention&utm_term=apache%2Fhugegraph>).* --- Docs are dead. 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