add multi query example

Author: rustagir

source/examples/atlas-examples/CompoundBoostMultiQuery.kt

@@ -0,0 +1,79 @@
+import com.mongodb.client.model.Aggregates.limit
+import com.mongodb.client.model.Aggregates.project
+import com.mongodb.client.model.Filters.eq
+import com.mongodb.client.model.Projections.*
+import com.mongodb.kotlin.client.coroutine.MongoClient
+import kotlinx.coroutines.runBlocking
+import org.bson.Document
+
+fun main() {
+    val uri = "<connection string>"
+    val mongoClient = MongoClient.create(uri)
+
+    val database = mongoClient.getDatabase("local_school_district")
+    val collection = database.getCollection<Document>("schools")
+
+    runBlocking {
+        val agg = Document("index", "compound-query-custom-score-tutorial")
+            .append(
+                "must", listOf(
+                    Document(
+                        "text",
+                        Document("path", "genres")
+                            .append("query", "comedy")
+                            .append(
+                                "score",
+                                Document(
+                                    "boost",
+                                    Document("value", 9)
+                                )
+                            )
+                    ),
+                    Document(
+                        "text",
+                        Document("path", "title")
+                            .append("query", "snow")
+                            .append(
+                                "score",
+                                Document(
+                                    "boost",
+                                    Document("value", 5)
+                                )
+                            )
+                    )
+                )
+            )
+            .append(
+                "should", listOf(
+                    Document(
+                        "range",
+                        Document("path", "year")
+                            .append("gte", 2013)
+                            .append("lte", 2015)
+                            .append(
+                                "score",
+                                Document(
+                                    "boost",
+                                    Document("value", 3)
+                                )
+                            )
+                    )
+                )
+            )
+
+        val resultsFlow = collection.aggregate<Document>(
+            listOf(
+                eq("\$search", eq("compound", agg)),
+                limit(10),
+                project(fields(
+                    excludeId(),
+                    include("title", "year","genres"),
+                    computed("score", Document("\$meta", "searchScore"))
+                ))
+            )
+        )
+        resultsFlow.collect { println(it) }
+    }
+    mongoClient.close()
+}
+