opendev/gerrit
Code Issues Proposed changes

RestApiServlet: Avoid using local field for trace ID as the instance may be reused

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It seems that instances of RestApiServlet can be reused for multiple
requests hence we must not use a local member field to store the trace
ID, since otherwise the trace ID of one request may be applied to
another request.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I83b667551fce85479bb9feab1a90f5ef69f14fdd
This commit is contained in:
Edwin Kempin
2019-11-27 13:32:52 +01:00
parent 00a77ac45e
commit 80477712f7
1 changed files with 11 additions and 7 deletions
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18
java/com/google/gerrit/httpd/restapi/RestApiServlet.java
View File

@@ -175,6 +175,7 @@ import java.util.Optional;
import java.util.Set;
import java.util.TreeMap;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;
import java.util.regex.Pattern;
import java.util.stream.Stream;
import java.util.zip.GZIPOutputStream;
@@ -291,7 +292,6 @@ public class RestApiServlet extends HttpServlet {
private final Globals globals;
private final Provider<RestCollection<RestResource, RestResource>> members;
private Optional<String> traceId = Optional.empty();
public RestApiServlet(
Globals globals, RestCollection<? extends RestResource, ? extends RestResource> members) {
@@ -666,7 +666,7 @@ public class RestApiServlet extends HttpServlet {
responseBytes = replyError(req, res, status = SC_SERVICE_UNAVAILABLE, "Lock failure", e);
} else {
status = SC_INTERNAL_SERVER_ERROR;
responseBytes = handleException(e, req, res);
responseBytes = handleException(traceContext, e, req, res);
}
} catch (QuotaException e) {
cause = Optional.of(e);
@@ -681,7 +681,7 @@ public class RestApiServlet extends HttpServlet {
} catch (Exception e) {
cause = Optional.of(e);
status = SC_INTERNAL_SERVER_ERROR;
responseBytes = handleException(e, req, res);
responseBytes = handleException(traceContext, e, req, res);
} finally {
String metric = getViewName(viewData);
String formattedCause = cause.map(globals.retryHelper::formatCause).orElse("_none");
@@ -814,6 +814,7 @@ public class RestApiServlet extends HttpServlet {
ActionType actionType,
Action<T> action)
throws Exception {
AtomicReference<Optional<String>> traceId = new AtomicReference<>(Optional.empty());
RetryHelper.Options.Builder retryOptionsBuilder = RetryHelper.options().caller(caller);
if (!traceContext.isTracing()) {
// enable automatic retry with tracing in case of non-recoverable failure
@@ -822,7 +823,7 @@ public class RestApiServlet extends HttpServlet {
.retryWithTrace(t -> !(t instanceof RestApiException))
.onAutoTrace(
autoTraceId -> {
traceId = Optional.of(autoTraceId);
traceId.set(Optional.of(autoTraceId));
// Include details of the request into the trace.
traceRequestData(req);
@@ -838,7 +839,9 @@ public class RestApiServlet extends HttpServlet {
// If auto-tracing got triggered due to a non-recoverable failure, also trace the rest of
// this request. This means logging is forced for all further log statements and the logs are
// associated with the same trace ID.
traceId.ifPresent(tid -> traceContext.addTag(RequestId.Type.TRACE_ID, tid).forceLogging());
traceId
.get()
.ifPresent(tid -> traceContext.addTag(RequestId.Type.TRACE_ID, tid).forceLogging());
}
}
@@ -1660,12 +1663,13 @@ public class RestApiServlet extends HttpServlet {
}
}
private long handleException(Throwable err, HttpServletRequest req, HttpServletResponse res)
private long handleException(
TraceContext traceContext, Throwable err, HttpServletRequest req, HttpServletResponse res)
throws IOException {
logger.atSevere().withCause(err).log("Error in %s %s", req.getMethod(), uriForLogging(req));
if (!res.isCommitted()) {
res.reset();
traceId.ifPresent(traceId -> res.addHeader(X_GERRIT_TRACE, traceId));
traceContext.getTraceId().ifPresent(traceId -> res.addHeader(X_GERRIT_TRACE, traceId));
StringBuilder msg = new StringBuilder("Internal server error");
ImmutableList<String> userMessages =
globals.exceptionHooks.stream()