Add support for multi terms aggregation

search_aggs_bucket_multi_terms.go

@@ -0,0 +1,313 @@
+// Copyright 2012-present Oliver Eilhard. All rights reserved.
+// Use of this source code is governed by a MIT-license.
+// See http://olivere.mit-license.org/license.txt for details.
+
+package elastic
+
+import "fmt"
+
+// A multi-bucket value source based aggregation where buckets are dynamically built - one per
+// unique set of values. The multi terms aggregation is very similar to the terms aggregation,
+// however in most cases it will be slower than the terms aggregation and will consume more
+// memory. Therefore, if the same set of fields is constantly used, it would be more efficient to
+// index a combined key for this fields as a separate field and use the terms aggregation on this field.
+//
+// See: https://www.elastic.co/guide/en/elasticsearch/reference/7.12/search-aggregations-bucket-multi-terms-aggregation.html
+type MultiTermsAggregation struct {
+	multiTerms      []*MultiTerm
+	subAggregations map[string]Aggregation
+	meta            map[string]interface{}
+
+	size                  *int
+	shardSize             *int
+	minDocCount           *int
+	shardMinDocCount      *int
+	collectionMode        string
+	showTermDocCountError *bool
+	order                 []MultiTermsOrder
+}
+
+func NewMultiTermsAggregation() *MultiTermsAggregation {
+	return &MultiTermsAggregation{
+		subAggregations: make(map[string]Aggregation),
+	}
+}
+
+func (a *MultiTermsAggregation) Terms(multiTerm ...*MultiTerm) *MultiTermsAggregation {
+	a.multiTerms = multiTerm
+	return a
+}
+
+func (a *MultiTermsAggregation) SubAggregation(name string, subAggregation Aggregation) *MultiTermsAggregation {
+	a.subAggregations[name] = subAggregation
+	return a
+}
+
+// Meta sets the meta data to be included in the aggregation response.
+func (a *MultiTermsAggregation) Meta(metaData map[string]interface{}) *MultiTermsAggregation {
+	a.meta = metaData
+	return a
+}
+
+func (a *MultiTermsAggregation) Size(size int) *MultiTermsAggregation {
+	a.size = &size
+	return a
+}
+
+func (a *MultiTermsAggregation) ShardSize(shardSize int) *MultiTermsAggregation {
+	a.shardSize = &shardSize
+	return a
+}
+
+func (a *MultiTermsAggregation) MinDocCount(minDocCount int) *MultiTermsAggregation {
+	a.minDocCount = &minDocCount
+	return a
+}
+
+func (a *MultiTermsAggregation) ShardMinDocCount(shardMinDocCount int) *MultiTermsAggregation {
+	a.shardMinDocCount = &shardMinDocCount
+	return a
+}
+
+func (a *MultiTermsAggregation) Order(order string, asc bool) *MultiTermsAggregation {
+	a.order = append(a.order, MultiTermsOrder{Field: order, Ascending: asc})
+	return a
+}
+
+func (a *MultiTermsAggregation) OrderByCount(asc bool) *MultiTermsAggregation {
+	// "order" : { "_count" : "asc" }
+	a.order = append(a.order, MultiTermsOrder{Field: "_count", Ascending: asc})
+	return a
+}
+
+func (a *MultiTermsAggregation) OrderByCountAsc() *MultiTermsAggregation {
+	return a.OrderByCount(true)
+}
+
+func (a *MultiTermsAggregation) OrderByCountDesc() *MultiTermsAggregation {
+	return a.OrderByCount(false)
+}
+
+func (a *MultiTermsAggregation) OrderByKey(asc bool) *MultiTermsAggregation {
+	// "order" : { "_term" : "asc" }
+	a.order = append(a.order, MultiTermsOrder{Field: "_key", Ascending: asc})
+	return a
+}
+
+func (a *MultiTermsAggregation) OrderByKeyAsc() *MultiTermsAggregation {
+	return a.OrderByKey(true)
+}
+
+func (a *MultiTermsAggregation) OrderByKeyDesc() *MultiTermsAggregation {
+	return a.OrderByKey(false)
+}
+
+// OrderByAggregation creates a bucket ordering strategy which sorts buckets
+// based on a single-valued calc get.
+func (a *MultiTermsAggregation) OrderByAggregation(aggName string, asc bool) *MultiTermsAggregation {
+	// {
+	// 	"aggs": {
+	// 	  "genres_and_products": {
+	// 		"multi_terms": {
+	// 		  "terms": [
+	// 			{
+	// 			  "field": "genre"
+	// 			},
+	// 			{
+	// 			  "field": "product"
+	// 			}
+	// 		  ],
+	// 		  "order": {
+	// 			"total_quantity": "desc"
+	// 		  }
+	// 		},
+	// 		"aggs": {
+	// 		  "total_quantity": {
+	// 			"sum": {
+	// 			  "field": "quantity"
+	// 			}
+	// 		  }
+	// 		}
+	// 	  }
+	// 	}
+	// }
+	a.order = append(a.order, MultiTermsOrder{Field: aggName, Ascending: asc})
+	return a
+}
+
+// OrderByAggregationAndMetric creates a bucket ordering strategy which
+// sorts buckets based on a multi-valued calc get.
+func (a *MultiTermsAggregation) OrderByAggregationAndMetric(aggName, metric string, asc bool) *MultiTermsAggregation {
+	// {
+	// 	"aggs": {
+	// 	  "genres_and_products": {
+	// 		"multi_terms": {
+	// 		  "terms": [
+	// 			{
+	// 			  "field": "genre"
+	// 			},
+	// 			{
+	// 			  "field": "product"
+	// 			}
+	// 		  ],
+	// 		  "order": {
+	// 			"total_quantity": "desc"
+	// 		  }
+	// 		},
+	// 		"aggs": {
+	// 		  "total_quantity": {
+	// 			"sum": {
+	// 			  "field": "quantity"
+	// 			}
+	// 		  }
+	// 		}
+	// 	  }
+	// 	}
+	// }
+	a.order = append(a.order, MultiTermsOrder{Field: aggName + "." + metric, Ascending: asc})
+	return a
+}
+
+// Collection mode can be depth_first or breadth_first as of 1.4.0.
+func (a *MultiTermsAggregation) CollectionMode(collectionMode string) *MultiTermsAggregation {
+	a.collectionMode = collectionMode
+	return a
+}
+
+func (a *MultiTermsAggregation) ShowTermDocCountError(showTermDocCountError bool) *MultiTermsAggregation {
+	a.showTermDocCountError = &showTermDocCountError
+	return a
+}
+
+func (a *MultiTermsAggregation) Source() (interface{}, error) {
+	// Example:
+	// {
+	// 	"aggs": {
+	// 	  "genres_and_products": {
+	// 		"multi_terms": {
+	// 		  "terms": [
+	// 			{
+	// 			  "field": "genre"
+	// 			},
+	// 			{
+	// 			  "field": "product"
+	// 			}
+	// 		  ]
+	// 		}
+	// 	  }
+	// 	}
+	// }
+	// This method returns only the "multi_terms": { "terms": [ { "field": "genre" }, { "field": "product" } ] } part.
+
+	source := make(map[string]interface{})
+	opts := make(map[string]interface{})
+	source["multi_terms"] = opts
+
+	// ValuesSourceAggregationBuilder
+	terms := make([]interface{}, len(a.multiTerms))
+	for i := range a.multiTerms {
+		if a.multiTerms[i] == nil {
+			return nil, fmt.Errorf("expected a multiterm but found a nil multiterm")
+		}
+		s, err := a.multiTerms[i].Source()
+		if err != nil {
+			return nil, err
+		}
+		terms[i] = s
+	}
+	opts["terms"] = terms
+
+	// TermsBuilder
+	if a.size != nil && *a.size >= 0 {
+		opts["size"] = *a.size
+	}
+	if a.shardSize != nil && *a.shardSize >= 0 {
+		opts["shard_size"] = *a.shardSize
+	}
+	if a.minDocCount != nil && *a.minDocCount >= 0 {
+		opts["min_doc_count"] = *a.minDocCount
+	}
+	if a.shardMinDocCount != nil && *a.shardMinDocCount >= 0 {
+		opts["shard_min_doc_count"] = *a.shardMinDocCount
+	}
+	if a.showTermDocCountError != nil {
+		opts["show_term_doc_count_error"] = *a.showTermDocCountError
+	}
+	if a.collectionMode != "" {
+		opts["collect_mode"] = a.collectionMode
+	}
+	if len(a.order) > 0 {
+		var orderSlice []interface{}
+		for _, order := range a.order {
+			src, err := order.Source()
+			if err != nil {
+				return nil, err
+			}
+			orderSlice = append(orderSlice, src)
+		}
+		opts["order"] = orderSlice
+	}
+
+	// AggregationBuilder (SubAggregations)
+	if len(a.subAggregations) > 0 {
+		aggsMap := make(map[string]interface{})
+		source["aggregations"] = aggsMap
+		for name, aggregate := range a.subAggregations {
+			src, err := aggregate.Source()
+			if err != nil {
+				return nil, err
+			}
+			aggsMap[name] = src
+		}
+	}
+
+	// Add Meta data if available
+	if len(a.meta) > 0 {
+		source["meta"] = a.meta
+	}
+
+	return source, nil
+}
+
+// MultiTermsOrder specifies a single order field for a multi terms aggregation.
+type MultiTermsOrder struct {
+	Field     string
+	Ascending bool
+}
+
+// Source returns serializable JSON of the MultiTermsOrder.
+func (order *MultiTermsOrder) Source() (interface{}, error) {
+	source := make(map[string]string)
+	if order.Ascending {
+		source[order.Field] = "asc"
+	} else {
+		source[order.Field] = "desc"
+	}
+	return source, nil
+}
+
+// MultiTerm specifies a single term field for a multi terms aggregation.
+type MultiTerm struct {
+	field   string
+	missing interface{}
+}
+
+// Source returns serializable JSON of the MultiTerm.
+func (term *MultiTerm) Source() (interface{}, error) {
+	source := make(map[string]interface{})
+	source["field"] = term.field
+	if term.missing != nil {
+		source["missing"] = term.missing
+	}
+	return source, nil
+}
+
+// Missing configures the value to use when document miss a value
+func (term *MultiTerm) Missing(missing interface{}) *MultiTerm {
+	term.missing = missing
+	return term
+}
+
+func NewMultiTerm(field string) *MultiTerm {
+	return &MultiTerm{field: field}
+}