CDRIVER-696: Store the topology_scanner node failure so we can report it later

Author: bjori

src/mongoc/mongoc-cluster.c

@@ -1255,7 +1255,7 @@ mongoc_cluster_node_reconnect (mongoc_cluster_t *cluster, uint32_t server_id, bs
 
       mongoc_stream_failed (scanner_node->stream);
       scanner_node->stream = NULL;
-      mongoc_topology_scanner_node_setup (scanner_node);
+      mongoc_topology_scanner_node_setup (scanner_node, error);
       if (scanner_node->stream && cluster->requires_auth) {
          sd = mongoc_topology_server_by_id (topology, server_id);
          if (!sd) {

src/mongoc/mongoc-topology-scanner-private.h

@@ -56,6 +56,7 @@ typedef struct mongoc_topology_scanner_node
    struct mongoc_topology_scanner_node *prev;
 
    bool                            retired;
+   bson_error_t                    last_error;
 } mongoc_topology_scanner_node_t;
 
 typedef struct mongoc_topology_scanner
@@ -116,7 +117,8 @@ void
 mongoc_topology_scanner_reset (mongoc_topology_scanner_t *ts);
 
 bool
-mongoc_topology_scanner_node_setup (mongoc_topology_scanner_node_t *node);
+mongoc_topology_scanner_node_setup (mongoc_topology_scanner_node_t *node,
+                                    bson_error_t *error);
 
 mongoc_topology_scanner_node_t *
 mongoc_topology_scanner_get_node (mongoc_topology_scanner_t *ts,

src/mongoc/mongoc-topology-scanner.c

@@ -124,7 +124,7 @@ mongoc_topology_scanner_add_and_scan (mongoc_topology_scanner_t *ts,
 
    node = mongoc_topology_scanner_add (ts, host, id);
 
-   if (node && mongoc_topology_scanner_node_setup (node)) {
+   if (node && mongoc_topology_scanner_node_setup (node, &node->last_error)) {
       node->cmd = mongoc_async_cmd (
          ts->async, node->stream, ts->setup,
          node->host.host, "admin",
@@ -405,23 +405,22 @@ mongoc_topology_scanner_node_connect_unix (mongoc_topology_scanner_node_t *node,
 }
 
 bool
-mongoc_topology_scanner_node_setup (mongoc_topology_scanner_node_t *node)
+mongoc_topology_scanner_node_setup (mongoc_topology_scanner_node_t *node, bson_error_t *error)
 {
    mongoc_stream_t *sock_stream;
-   bson_error_t error = { 0 };
 
    if (node->stream) { return true; }
 
    BSON_ASSERT (!node->retired);
 
    if (node->ts->initiator) {
       sock_stream = node->ts->initiator (node->ts->uri, &node->host,
-                                         node->ts->initiator_context, &error);
+                                         node->ts->initiator_context, error);
    } else {
       if (node->host.family == AF_UNIX) {
-         sock_stream = mongoc_topology_scanner_node_connect_unix (node, &error);
+         sock_stream = mongoc_topology_scanner_node_connect_unix (node, error);
       } else {
-         sock_stream = mongoc_topology_scanner_node_connect_tcp (node, &error);
+         sock_stream = mongoc_topology_scanner_node_connect_tcp (node, error);
       }
 
 #ifdef MONGOC_ENABLE_SSL
@@ -433,7 +432,7 @@ mongoc_topology_scanner_node_setup (mongoc_topology_scanner_node_t *node)
 
    if (!sock_stream) {
       /* Pass a rtt of -1 if we couldn't initialize a stream in node_setup */
-      node->ts->cb (node->id, NULL, -1, node->ts->cb_data, &error);
+      node->ts->cb (node->id, NULL, -1, node->ts->cb_data, error);
       return false;
    }
 
@@ -491,7 +490,7 @@ mongoc_topology_scanner_start (mongoc_topology_scanner_t *ts,
    {
       /* check node if it last failed before current cooldown period began */
       if (node->last_failed < cooldown) {
-         if (mongoc_topology_scanner_node_setup (node)) {
+         if (mongoc_topology_scanner_node_setup (node, &node->last_error)) {
 
             BSON_ASSERT (!node->cmd);