MongoDB Java driver has been impacted by two server bugs, SERVER-113344 and SERVER-113026, and failed to parse the unexpected bulkWrite responses produced by these bugs.

This ticket is to investigate whether the Go driver is affected by the same server behavior when using client bulkWrite and mitigate the issue.

On a sharded collection where the operation goes through the "without shard key" path (the filter does not contain the shard key):

• SERVER-113344: For client bulkWrite with errorsOnly: true, the server still returns a successful per-operation result in the cursor instead of returning only errors.
  • In the Java driver, we now ignore such unexpected successful results in the cursor (we do not return them to the application).

• SERVER-113026: For client bulkWrite with errorsOnly: false, nModified is not included by the server in the individual operation result (in the cursor).
  • In the Java driver, we now treat a missing nModified in this case as 0 when decoding.

The Java driver previously hit parsing/decoding errors when it encountered these unexpected reply shapes. Reproduction steps are described in this document (they apply to both server issues): Link.