Use Case

As a write concern 0 user
I want the driver to set the fire-and-forget bit
So that the server handles the unacknowledged write as expected

See spec:
https://github.com/mongodb/specifications/blob/master/source/message/OP_MSG.rst#moretocome-on-requests

User Impact

• Has the potential to change the outcome of writes, operations that once would fail could now succeed.

Dependencies

• None

Acceptance Criteria

Implementation Requirements

• If the command being run has a writeConcern w setting of 0
  • set the moreToCome bit on the outgoing OP_MSG message.
  • return the command without waiting for a server response

Testing Requirements

• Integration:
  • ensure if writeConcern w = 0 on the command,
    • moreToCome bit is set in outgoing request
    • commandSucceededEvent's reply only contain { ok: 1 }
• Unit:
  • ensure if writeConcern w = 0 on the command, moreToCome is set in OP_MSG

Documentation Requirements

• Update TSDoc over "w" settings to mention the side-effect of setting w:0 on the protocol message.

Follow Up Requirements

• None