Aggregation Pipeline Stage - $unwind

Build the $unwind stage through the aggregation pipeline stage builder aggregation.NewStageBuilder using the method Unwind.

type User struct {
	mongox.Model `bson:"inline"`
	Name         string `bson:"name"`
	Age          int    `bson:"age"`
	Hobbies      []string `bson:"hobbies"`
}

// mongo.Pipeline{bson.D{bson.E{Key:"$unwind", Value:"$hobbies"}}}
//[
//  {
//    "$unwind": "$hobbies"
//  }
//]
aggregation.NewStageBuilder().Unwind("$hobbies", nil).Build()

The Unwind method has two parameters: path string and opt *types.UnWindOptions. The opt parameter is optional and can be nil. It is used to specify the includeArrayIndex and preserveNullAndEmptyArrays options.