Conversion API from BSON to JSON values
JSON representation for numbers
JSON representation for temporal types
See syntax:
{ "$numberDecimal": "<number>" }
Converts to a JSON object
First checks whether an explicit type (e.g. $binary) is specified, otherwise converts to a BSON document.
$binary
{ "$maxKey": 1 }
{ "$minKey": 1 }
{ "$undefined": true }