105 lines
2.9 KiB
Go
105 lines
2.9 KiB
Go
|
// 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/6.2/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
|
||
|
|
}
|