CDRIVER-2609 fix empty error after ismaster fails

Author: ajdavis

src/mongoc/mongoc-cluster.c

@@ -625,12 +625,12 @@ static mongoc_server_description_t *
 _mongoc_stream_run_ismaster (mongoc_cluster_t *cluster,
                              mongoc_stream_t *stream,
                              const char *address,
-                             uint32_t server_id)
+                             uint32_t server_id,
+                             bson_error_t *error)
 {
    const bson_t *command;
    mongoc_cmd_parts_t parts;
    bson_t reply;
-   bson_error_t error;
    int64_t start;
    int64_t rtt_msec;
    mongoc_server_description_t *sd;
@@ -647,7 +647,7 @@ _mongoc_stream_run_ismaster (mongoc_cluster_t *cluster,
 
    start = bson_get_monotonic_time ();
    server_stream = _mongoc_cluster_create_server_stream (
-      cluster->client->topology, server_id, stream, &error);
+      cluster->client->topology, server_id, stream, error);
    if (!server_stream) {
       RETURN (NULL);
    }
@@ -656,7 +656,8 @@ _mongoc_stream_run_ismaster (mongoc_cluster_t *cluster,
       &parts, cluster->client, "admin", MONGOC_QUERY_SLAVE_OK, command);
    parts.prohibit_lsid = true;
    if (!mongoc_cluster_run_command_parts (
-          cluster, server_stream, &parts, &reply, &error)) {
+      cluster, server_stream, &parts, &reply, error)) {
+      bson_destroy (&reply);
       mongoc_server_stream_cleanup (server_stream);
       RETURN (NULL);
    }
@@ -668,7 +669,7 @@ _mongoc_stream_run_ismaster (mongoc_cluster_t *cluster,
 
    mongoc_server_description_init (sd, address, server_id);
    /* send the error from run_command IN to handle_ismaster */
-   mongoc_server_description_handle_ismaster (sd, &reply, rtt_msec, &error);
+   mongoc_server_description_handle_ismaster (sd, &reply, rtt_msec, error);
 
    bson_destroy (&reply);
 
@@ -719,7 +720,7 @@ _mongoc_cluster_run_ismaster (mongoc_cluster_t *cluster,
    BSON_ASSERT (node->stream);
 
    sd = _mongoc_stream_run_ismaster (
-      cluster, node->stream, node->connection_address, server_id);
+      cluster, node->stream, node->connection_address, server_id, error);
 
    if (!sd) {
       return NULL;
@@ -1742,7 +1743,7 @@ mongoc_cluster_fetch_stream_single (mongoc_cluster_t *cluster,
 #endif
 
       sd = _mongoc_stream_run_ismaster (
-         cluster, stream, scanner_node->host.host_and_port, server_id);
+         cluster, stream, scanner_node->host.host_and_port, server_id, error);
 
       if (!sd) {
          return NULL;

tests/test-mongoc-cluster.c

@@ -1306,7 +1306,7 @@ dollar_query_test_t tests[] = {
    {NULL}};
 
 static void
-test_cluster_ismaster_fails (void)
+_test_cluster_ismaster_fails (bool hangup)
 {
    mock_server_t *mock_server;
    mongoc_uri_t *uri;
@@ -1326,6 +1326,7 @@ test_cluster_ismaster_fails (void)
    /* increase heartbeatFrequencyMS to prevent background server selection. */
    mongoc_uri_set_option_as_int32 (uri, "heartbeatFrequencyMS", 99999);
    pool = mongoc_client_pool_new (uri);
+   mongoc_client_pool_set_error_api (pool, 2);
    mongoc_uri_destroy (uri);
    client = mongoc_client_pool_pop (pool);
    /* do server selection to add this server to the topology. this does not add
@@ -1343,15 +1344,41 @@ test_cluster_ismaster_fails (void)
    /* CDRIVER-2576: the server replies with an error, so
     * _mongoc_stream_run_ismaster returns NULL, which
     * _mongoc_cluster_run_ismaster must check. */
-   mock_server_replies_simple (request, "{'ok': 0}");
+
+   if (hangup) {
+      capture_logs (true); /* suppress "failed to buffer" warning */
+      mock_server_hangs_up (request);
+      BSON_ASSERT (!future_get_bool (future));
+      ASSERT_ERROR_CONTAINS (
+         error, MONGOC_ERROR_STREAM, MONGOC_ERROR_STREAM_SOCKET, "socket err");
+   } else {
+      mock_server_replies_simple (request, "{'ok': 0, 'code': 123}");
+      BSON_ASSERT (!future_get_bool (future));
+      ASSERT_ERROR_CONTAINS (
+         error, MONGOC_ERROR_SERVER, 123, "Unknown command error");
+   }
+
    request_destroy (request);
-   future_wait (future);
    future_destroy (future);
    mock_server_destroy (mock_server);
    mongoc_client_pool_push (pool, client);
    mongoc_client_pool_destroy (pool);
 }
 
+static void
+test_cluster_ismaster_fails (void)
+{
+   _test_cluster_ismaster_fails (false);
+}
+
+
+static void
+test_cluster_ismaster_hangup (void)
+{
+   _test_cluster_ismaster_fails (true);
+}
+
+
 void
 test_cluster_install (TestSuite *suite)
 {
@@ -1474,4 +1501,6 @@ test_cluster_install (TestSuite *suite)
                                 test_framework_skip_if_slow);
    TestSuite_AddMockServerTest (
       suite, "/Cluster/ismaster_fails", test_cluster_ismaster_fails);
+   TestSuite_AddMockServerTest (
+      suite, "/Cluster/ismaster_hangup", test_cluster_ismaster_hangup);
 }