(dsl): Support constantScore query (#307)

docs/overview/queries/elastic_query_constant_score.md

@@ -0,0 +1,30 @@
+---
+id: elastic_query_constant_score
+title: "Constant Score Query"
+---
+
+The `ConstantScore` query wraps a filter query and returns every matching document with a relevance score equal to the boost parameter value.
+
+In order to use the `ConstantScore` query import the following:
+```scala
+import zio.elasticsearch.query.ConstantScoreQuery
+import zio.elasticsearch.ElasticQuery._
+```
+
+You can create a `ConstantScore` query with arbitrary query(`MatchPhrase` in this example) using the `constantScore` method in the following manner:
+```scala
+val query: ConstantScoreQuery = constantScore(matchPhrase(field = "name", value = "test"))
+```
+
+You can create a [type-safe](https://lambdaworks.github.io/zio-elasticsearch/overview/overview_zio_prelude_schema) `ConstantScore` query with arbitrary [type-safe](https://lambdaworks.github.io/zio-elasticsearch/overview/overview_zio_prelude_schema) query(`MatchPhrase` in this example) using the `constantScore` method in the following manner:
+```scala
+val query: ConstantScoreQuery = constantScore(matchPhrase(field = Document.name, value = "test"))
+```
+
+If you want to change the `boost`, you can use `boost` method:
+```scala
+val queryWithBoost: ConstantScoreQuery = constantScore(matchPhrase(field = Document.name, value = "test")).boost(2.2)
+```
+
+You can find more information about `ConstantScore` query [here](https://www.elastic.co/guide/en/elasticsearch/reference/7.17/query-dsl-constant-score-query.html).
+

modules/integration/src/test/scala/zio/elasticsearch/HttpExecutorSpec.scala

@@ -724,6 +724,32 @@ object HttpExecutorSpec extends IntegrationSpec {
           )
         ),
         suite("searching for documents")(
+          test("search for a document using a constant score query") {
+            checkOnce(genDocumentId, genTestDocument, genDocumentId, genTestDocument) {
+              (firstDocumentId, firstDocument, secondDocumentId, secondDocument) =>
+                for {
+                  _       <- Executor.execute(ElasticRequest.deleteByQuery(firstSearchIndex, matchAll))
+                  document = firstDocument.copy(stringField = "this is a test")
+                  _ <-
+                    Executor.execute(ElasticRequest.upsert[TestDocument](firstSearchIndex, firstDocumentId, document))
+                  _ <- Executor.execute(
+                         ElasticRequest
+                           .upsert[TestDocument](firstSearchIndex, secondDocumentId, secondDocument)
+                           .refreshTrue
+                       )
+                  query = constantScore(
+                            matchPhrase(
+                              field = TestDocument.stringField,
+                              value = "test"
+                            )
+                          ).boost(2.1)
+                  res <- Executor.execute(ElasticRequest.search(firstSearchIndex, query)).documentAs[TestDocument]
+                } yield (assert(res)(Assertion.contains(document)) && assert(res)(!Assertion.contains(secondDocument)))
+            }
+          } @@ around(
+            Executor.execute(ElasticRequest.createIndex(firstSearchIndex)),
+            Executor.execute(ElasticRequest.deleteIndex(firstSearchIndex)).orDie
+          ),
           test("search for first 2 documents using range query") {
             checkOnce(genDocumentId, genTestDocument, genDocumentId, genTestDocument, genDocumentId, genTestDocument) {
               (firstDocumentId, firstDocument, secondDocumentId, secondDocument, thirdDocumentId, thirdDocument) =>

modules/library/src/main/scala/zio/elasticsearch/ElasticQuery.scala

@@ -25,6 +25,36 @@ import zio.schema.Schema
 
 object ElasticQuery {
 
+  /**
+   * Constructs a type-safe instance of [[zio.elasticsearch.query.ConstantScoreQuery]] with a specified query.
+   * [[zio.elasticsearch.query.ConstantScoreQuery]] wraps a filter query and returns every matching document with a
+   * relevance score equal to the boost parameter value.
+   *
+   * @param query
+   *   query to be wrapped inside of constant score query
+   * @tparam S
+   *   document for which field query is specified for. An implicit `Schema` instance must be provided in the scope
+   * @return
+   *   an instance of [[zio.elasticsearch.query.ConstantScoreQuery]] that represents the constant score query with query
+   *   that must satisfy the criteria to be performed.
+   */
+  final def constantScore[S: Schema](query: ElasticQuery[S]): ConstantScoreQuery[S] =
+    ConstantScore[S](query = query, boost = None)
+
+  /**
+   * Constructs an instance of [[zio.elasticsearch.query.ConstantScoreQuery]] with a specified query.
+   * [[zio.elasticsearch.query.ConstantScoreQuery]] wraps a filter query and returns every matching document with a
+   * relevance score equal to the boost parameter value.
+   *
+   * @param query
+   *   query to be wrapped inside of constant score query
+   * @return
+   *   an instance of [[zio.elasticsearch.query.ConstantScoreQuery]] that represents the constant score query with query
+   *   that must satisfy the criteria to be performed.
+   */
+  final def constantScore(query: ElasticQuery[Any]): ConstantScoreQuery[Any] =
+    ConstantScore[Any](query = query, boost = None)
+
   /**
    * Constructs a type-safe instance of [[zio.elasticsearch.query.WildcardQuery]] using the specified parameters.
    * [[zio.elasticsearch.query.WildcardQuery]] is used for matching documents containing a value that contains the

modules/library/src/main/scala/zio/elasticsearch/query/Queries.scala

@@ -182,6 +182,22 @@ private[elasticsearch] final case class Bool[S](
   }
 }
 
+sealed trait ConstantScoreQuery[S] extends ElasticQuery[S] with HasBoost[ConstantScoreQuery[S]]
+
+private[elasticsearch] final case class ConstantScore[S](query: ElasticQuery[S], boost: Option[Double])
+    extends ConstantScoreQuery[S] { self =>
+
+  def boost(value: Double): ConstantScoreQuery[S] =
+    self.copy(boost = Some(value))
+
+  private[elasticsearch] def toJson(fieldPath: Option[String]): Json =
+    Obj(
+      "constant_score" -> (Obj("filter" -> query.toJson(fieldPath)) merge boost.fold(Obj())(b =>
+        Obj("boost" -> b.toJson)
+      ))
+    )
+}
+
 sealed trait ExistsQuery[S] extends ElasticQuery[S] with HasBoost[ExistsQuery[S]]
 
 private[elasticsearch] final case class Exists[S](field: String, boost: Option[Double]) extends ExistsQuery[S] { self =>

modules/library/src/test/scala/zio/elasticsearch/ElasticQuerySpec.scala

@@ -333,6 +333,36 @@ object ElasticQuerySpec extends ZIOSpecDefault {
             )
           }
         ),
+        test("constantScore") {
+          val query          = constantScore(terms("stringField", "a", "b", "c"))
+          val queryTs        = constantScore(terms(TestDocument.stringField, "a", "b", "c"))
+          val queryWithBoost = constantScore(terms(TestDocument.stringField, "a", "b", "c")).boost(2.2)
+
+          assert(query)(
+            equalTo(
+              ConstantScore[Any](
+                Terms(field = "stringField", values = Chunk("a", "b", "c"), boost = None),
+                boost = None
+              )
+            )
+          ) &&
+          assert(queryTs)(
+            equalTo(
+              ConstantScore[TestDocument](
+                Terms(field = "stringField", values = Chunk("a", "b", "c"), boost = None),
+                boost = None
+              )
+            )
+          ) &&
+          assert(queryWithBoost)(
+            equalTo(
+              ConstantScore[TestDocument](
+                Terms(field = "stringField", values = Chunk("a", "b", "c"), boost = None),
+                boost = Some(2.2)
+              )
+            )
+          )
+        },
         test("contains") {
           val query                    = contains("testField", "test")
           val queryTs                  = contains(TestDocument.stringField, "test")
@@ -1924,6 +1954,41 @@ object ElasticQuerySpec extends ZIOSpecDefault {
             assert(queryWithAllParams.toJson(fieldPath = None))(equalTo(expectedWithAllParams.toJson))
           }
         ),
+        test("constantScore") {
+          val query          = constantScore(matchPhrase("stringField", "test"))
+          val queryTs        = constantScore(matchPhrase(TestDocument.stringField, "test"))
+          val queryWithBoost = constantScore(matchPhrase(TestDocument.stringField, "test")).boost(1.5)
+
+          val expected =
+            """
+              |{
+              |  "constant_score": {
+              |    "filter": {
+              |      "match_phrase": {
+              |         "stringField": "test"
+              |      }
+              |    }
+              |  }
+              |}
+              |""".stripMargin
+          val expectedWithBoost =
+            """
+              |{
+              |  "constant_score": {
+              |    "filter": {
+              |      "match_phrase": {
+              |         "stringField": "test"
+              |      }
+              |    },
+              |    "boost": 1.5
+              |  }
+              |}
+              |""".stripMargin
+
+          assert(query.toJson(fieldPath = None))(equalTo(expected.toJson)) &&
+          assert(queryTs.toJson(fieldPath = None))(equalTo(expected.toJson)) &&
+          assert(queryWithBoost.toJson(fieldPath = None))(equalTo(expectedWithBoost.toJson))
+        },
         test("contains") {
           val query                    = contains(TestDocument.stringField, "test")
           val queryWithBoost           = contains(TestDocument.stringField, "test").boost(3.14)

website/sidebars.js

@@ -15,6 +15,7 @@ module.exports = {
                 items: [
                     'overview/elastic_query',
                     'overview/queries/elastic_query_bool',
+                    'overview/queries/elastic_query_constant_score',
                     'overview/queries/elastic_query_exists',
                     'overview/queries/elastic_query_function_score',
                     'overview/queries/elastic_query_geo_distance',