CDRIVER-4754 pre-4.4 mongos writeConcernError does not determine retryability (#1501)

Synced with mongodb/specifications@3e60a7c

Author: jmikola

src/libmongoc/src/mongoc/mongoc-client.c

@@ -1712,8 +1712,7 @@ _mongoc_client_retryable_write_command_with_stream (
    ret = mongoc_cluster_run_command_monitored (
       &client->cluster, &parts->assembled, reply, error);
 
-   _mongoc_write_error_handle_labels (
-      ret, error, reply, server_stream->sd->max_wire_version);
+   _mongoc_write_error_handle_labels (ret, error, reply, server_stream->sd);
 
    if (is_retryable) {
       _mongoc_write_error_update_if_unsupported_storage_engine (

src/libmongoc/src/mongoc/mongoc-cluster.c

@@ -530,7 +530,7 @@ _handle_txn_error_labels (bool cmd_ret,
    }
 
    _mongoc_write_error_handle_labels (
-      cmd_ret, cmd_err, reply, cmd->server_stream->sd->max_wire_version);
+      cmd_ret, cmd_err, reply, cmd->server_stream->sd);
 }
 
 /*

src/libmongoc/src/mongoc/mongoc-collection.c

@@ -3548,7 +3548,7 @@ mongoc_collection_find_and_modify_with_opts (
 
    if (parts.is_retryable_write) {
       _mongoc_write_error_handle_labels (
-         ret, error, reply_ptr, server_stream->sd->max_wire_version);
+         ret, error, reply_ptr, server_stream->sd);
    }
 
    if (is_retryable) {

src/libmongoc/src/mongoc/mongoc-error-private.h

@@ -19,6 +19,8 @@
 #include <bson/bson.h>
 #include <stddef.h>
 
+#include "mongoc-server-description.h"
+
 BSON_BEGIN_DECLS
 
 typedef enum {
@@ -72,7 +74,7 @@ void
 _mongoc_write_error_handle_labels (bool cmd_ret,
                                    const bson_error_t *cmd_err,
                                    bson_t *reply,
-                                   int32_t server_max_wire_version);
+                                   mongoc_server_description_t *sd);
 
 bool
 _mongoc_error_is_shutdown (bson_error_t *error);

src/libmongoc/src/mongoc/mongoc-error.c

@@ -20,6 +20,7 @@
 #include "mongoc-error-private.h"
 #include "mongoc-rpc-private.h"
 #include "mongoc-client-private.h"
+#include "mongoc-server-description-private.h"
 
 bool
 mongoc_error_has_label (const bson_t *reply, const char *label)
@@ -102,7 +103,7 @@ void
 _mongoc_write_error_handle_labels (bool cmd_ret,
                                    const bson_error_t *cmd_err,
                                    bson_t *reply,
-                                   int32_t server_max_wire_version)
+                                   mongoc_server_description_t *sd)
 {
    bson_error_t error;
 
@@ -115,14 +116,21 @@ _mongoc_write_error_handle_labels (bool cmd_ret,
       return;
    }
 
-   if (server_max_wire_version >= WIRE_VERSION_RETRYABLE_WRITE_ERROR_LABEL) {
+   if (sd->max_wire_version >= WIRE_VERSION_RETRYABLE_WRITE_ERROR_LABEL) {
       return;
    }
 
-   /* check for a server error. */
-   if (_mongoc_cmd_check_ok_no_wce (
-          reply, MONGOC_ERROR_API_VERSION_2, &error)) {
-      return;
+   /* Check for a server error. Do not consult writeConcernError for pre-4.4
+    * mongos. */
+   if (sd->type == MONGOC_SERVER_MONGOS) {
+      if (_mongoc_cmd_check_ok (reply, MONGOC_ERROR_API_VERSION_2, &error)) {
+         return;
+      }
+   } else {
+      if (_mongoc_cmd_check_ok_no_wce (
+             reply, MONGOC_ERROR_API_VERSION_2, &error)) {
+         return;
+      }
    }
 
    if (_mongoc_write_error_is_retryable (&error)) {

src/libmongoc/src/mongoc/mongoc-write-command.c

@@ -750,7 +750,7 @@ _mongoc_write_opmsg (mongoc_write_command_t *command,
 
          if (parts.is_retryable_write) {
             _mongoc_write_error_handle_labels (
-               ret, error, &reply, server_stream->sd->max_wire_version);
+               ret, error, &reply, server_stream->sd);
          }
 
          /* Add this batch size so we skip these documents next time */