File: search_queries_dis_max.go

package info (click to toggle)
golang-gopkg-olivere-elastic.v5 5.0.83-1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, sid
  • size: 2,848 kB
  • sloc: makefile: 18; sh: 2
file content (104 lines) | stat: -rw-r--r-- 2,928 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
// 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

// DisMaxQuery is a query that generates the union of documents produced by
// its subqueries, and that scores each document with the maximum score
// for that document as produced by any subquery, plus a tie breaking
// increment for any additional matching subqueries.
//
// For more details, see:
// https://www.elastic.co/guide/en/elasticsearch/reference/5.2/query-dsl-dis-max-query.html
type DisMaxQuery struct {
	queries    []Query
	boost      *float64
	tieBreaker *float64
	queryName  string
}

// NewDisMaxQuery creates and initializes a new dis max query.
func NewDisMaxQuery() *DisMaxQuery {
	return &DisMaxQuery{
		queries: make([]Query, 0),
	}
}

// Query adds one or more queries to the dis max query.
func (q *DisMaxQuery) Query(queries ...Query) *DisMaxQuery {
	q.queries = append(q.queries, queries...)
	return q
}

// Boost sets the boost for this query. Documents matching this query will
// (in addition to the normal weightings) have their score multiplied by
// the boost provided.
func (q *DisMaxQuery) Boost(boost float64) *DisMaxQuery {
	q.boost = &boost
	return q
}

// TieBreaker is the factor by which the score of each non-maximum disjunct
// for a document is multiplied with and added into the final score.
//
// If non-zero, the value should be small, on the order of 0.1, which says
// that 10 occurrences of word in a lower-scored field that is also in a
// higher scored field is just as good as a unique word in the lower scored
// field (i.e., one that is not in any higher scored field).
func (q *DisMaxQuery) TieBreaker(tieBreaker float64) *DisMaxQuery {
	q.tieBreaker = &tieBreaker
	return q
}

// QueryName sets the query name for the filter that can be used
// when searching for matched filters per hit.
func (q *DisMaxQuery) QueryName(queryName string) *DisMaxQuery {
	q.queryName = queryName
	return q
}

// Source returns the JSON serializable content for this query.
func (q *DisMaxQuery) Source() (interface{}, error) {
	// {
	//  "dis_max" : {
	//    "tie_breaker" : 0.7,
	//    "boost" : 1.2,
	//    "queries" : {
	//      {
	//        "term" : { "age" : 34 }
	//      },
	//      {
	//        "term" : { "age" : 35 }
	//      }
	//    ]
	//  }
	// }

	query := make(map[string]interface{})
	params := make(map[string]interface{})
	query["dis_max"] = params

	if q.tieBreaker != nil {
		params["tie_breaker"] = *q.tieBreaker
	}
	if q.boost != nil {
		params["boost"] = *q.boost
	}
	if q.queryName != "" {
		params["_name"] = q.queryName
	}

	// queries
	var clauses []interface{}
	for _, subQuery := range q.queries {
		src, err := subQuery.Source()
		if err != nil {
			return nil, err
		}
		clauses = append(clauses, src)
	}
	params["queries"] = clauses

	return query, nil
}