func NewSearchSource() *SearchSource {
	return &SearchSource{
		from:         -1,
		size:         -1,
		aggregations: make(map[string]Aggregation),
		indexBoosts:  make(map[string]float64),
		innerHits:    make(map[string]*InnerHit),
	}
}
NewSearchSource initializes a new SearchSource.
package elastic
import (
	"fmt"
)
type SearchSource struct {
	query                    Query
	postQuery                Query
	sliceQuery               Query
	from                     int
	size                     int
	explain                  *bool
	version                  *bool
	sorters                  []Sorter
	trackScores              *bool
	trackTotalHits           *bool
	searchAfterSortValues    []interface{}
	minScore                 *float64
	timeout                  string
	terminateAfter           *int
	storedFieldNames         []string
	docvalueFields           DocvalueFields
	scriptFields             []*ScriptField
	fetchSourceContext       *FetchSourceContext
	aggregations             map[string]Aggregation
	highlight                *Highlight
	globalSuggestText        string
	suggesters               []Suggester
	rescores                 []*Rescore
	defaultRescoreWindowSize *int
	indexBoosts              map[string]float64
	stats                    []string
	innerHits                map[string]*InnerHit
	collapse                 *CollapseBuilder
	profile                  bool
}