feat(java-shell): support cursor.readConcern (#486)

Author: kornilova203

packages/java-shell/src/main/kotlin/com/mongodb/mongosh/service/BaseMongoIterableHelper.kt

@@ -1,14 +1,13 @@
 package com.mongodb.mongosh.service
 
-import com.mongodb.CursorType
-import com.mongodb.ReadPreference
-import com.mongodb.TagSet
+import com.mongodb.*
 import com.mongodb.client.AggregateIterable
 import com.mongodb.client.FindIterable
 import com.mongodb.client.MongoDatabase
 import com.mongodb.client.MongoIterable
 import com.mongodb.client.model.CountOptions
 import com.mongodb.mongosh.MongoShellConverter
+import com.mongodb.mongosh.result.DocumentResult
 import org.bson.Document
 import org.graalvm.polyglot.Value
 
@@ -49,7 +48,7 @@ internal abstract class BaseMongoIterableHelper<T : MongoIterable<*>>(val iterab
     open fun tailable(): Unit = throw NotImplementedError("tailable is not supported")
     open fun explain(verbosity: String?): Any? = throw NotImplementedError("explain is not supported")
     open fun readPrev(v: String, tags: List<TagSet>?): BaseMongoIterableHelper<*> = throw NotImplementedError("readPrev is not supported")
-    open fun readConcern(v: String, tags: List<TagSet>?): BaseMongoIterableHelper<*> = throw NotImplementedError("readConcern is not supported")
+    open fun readConcern(v: Value): BaseMongoIterableHelper<*> = throw NotImplementedError("readConcern is not supported")
 
     protected fun set(key: String, value: Any?) {
         options[key] = value
@@ -95,6 +94,15 @@ internal class AggregateIterableHelper(iterable: AggregateIterable<*>,
         return AggregateIterableHelper(newIterable, converter, options, newCreateOptions)
     }
 
+    override fun readConcern(v: Value): AggregateIterableHelper {
+        check(createOptions != null) { "createOptions were not saved" }
+        if (!v.hasMembers()) throw IllegalArgumentException("document was expected. Got $v")
+        val newDb = readConcernConverter(createOptions.db, (converter.toJava(v) as DocumentResult).value).getOrThrow()
+        val newCreateOptions = createOptions.copy(db = newDb)
+        val newIterable = aggregate(options, newCreateOptions)
+        return AggregateIterableHelper(newIterable, converter, options, newCreateOptions)
+    }
+
     override fun maxTimeMS(v: Long) = set("maxTimeMS", v)
     override fun comment(v: String) = set("comment", v)
     override fun hint(v: Document) = set("hint", v)
@@ -142,6 +150,15 @@ internal class FindIterableHelper(iterable: FindIterable<out Any?>,
         return FindIterableHelper(newIterable, converter, options, newCreateOptions)
     }
 
+    override fun readConcern(v: Value): FindIterableHelper {
+        check(createOptions != null) { "createOptions were not saved" }
+        if (!v.hasMembers()) throw IllegalArgumentException("document was expected. Got $v")
+        val newDb = readConcernConverter(createOptions.db, (converter.toJava(v) as DocumentResult).value).getOrThrow()
+        val newCreateOptions = createOptions.copy(db = newDb)
+        val newIterable = find(options, newCreateOptions)
+        return FindIterableHelper(newIterable, converter, options, newCreateOptions)
+    }
+
     override fun allowPartialResults() = set("allowPartialResults", true)
     override fun oplogReplay() = set("oplogReplay", true)
     override fun noCursorTimeout() = set("noCursorTimeout", true)

packages/java-shell/src/main/kotlin/com/mongodb/mongosh/service/Cursor.kt

@@ -231,9 +231,9 @@ internal class Cursor(private var helper: BaseMongoIterableHelper<*>, private va
     }
 
     @HostAccess.Export
-    override fun withReadConcern(v: String): Cursor {
+    override fun withReadConcern(v: Value): Cursor {
         checkQueryNotExecuted()
-        helper = helper.readConcern(v, null)
+        helper = helper.readConcern(v)
         return this
     }
 

packages/java-shell/src/main/kotlin/com/mongodb/mongosh/service/ServiceProviderCursor.kt

@@ -29,7 +29,7 @@ interface ServiceProviderCursor {
   fun project(v: Value): ServiceProviderCursor
   fun returnKey(v: Value): ServiceProviderCursor
   fun withReadPreference(v: String): ServiceProviderCursor
-  fun withReadConcern(v: String): ServiceProviderCursor
+  fun withReadConcern(v: Value): ServiceProviderCursor
   fun showRecordId(v: Boolean): ServiceProviderCursor
   fun size(): Value
   fun skip(v: Int): ServiceProviderCursor

packages/java-shell/src/main/kotlin/com/mongodb/mongosh/service/optionConverters.kt

@@ -58,14 +58,26 @@ internal val writeConcernConverters: Map<String, (MongoDatabase, Any?) -> Either
 
 internal val writeConcernDefaultConverter = unrecognizedField<MongoDatabase>("write concern")
 
+
+internal val readConcernConverter: (MongoDatabase, Any?) -> Either<MongoDatabase> = { db, value ->
+    if (value is Map<*, *>) convert(db, readConcernConverters, readConcernDefaultConverter, value)
+    else Left(CommandException("invalid parameter: expected an object (readConcern)", "FailedToParse"))
+}
+
+internal val readConcernConverters: Map<String, (MongoDatabase, Any?) -> Either<MongoDatabase>> = mapOf(
+        typed("level", String::class.java) { db, value ->
+            db.withReadConcern(ReadConcern(ReadConcernLevel.fromString(value)))
+        }
+)
+
+internal val readConcernDefaultConverter = unrecognizedField<MongoDatabase>("read concern")
+
+
 internal val dbConverters: Map<String, (MongoDatabase, Any?) -> Either<MongoDatabase>> = mapOf(
         typed("writeConcern", Map::class.java) { db, value ->
             convert(db, writeConcernConverters, writeConcernDefaultConverter, value).getOrThrow()
         },
-        "readConcern" to { db, value ->
-            if (value is Map<*, *>) convert(db, readConcernConverters, readConcernDefaultConverter, value)
-            else Left(CommandException("invalid parameter: expected an object (readConcern)", "FailedToParse"))
-        },
+        "readConcern" to readConcernConverter,
         "readPreference" to { db, value ->
             if (value is Map<*, *>) convert(db, readPreferenceConverters, readPreferenceDefaultConverter, value)
             else Left(CommandException("invalid parameter: expected an object (readPreference)", "FailedToParse"))
@@ -74,14 +86,6 @@ internal val dbConverters: Map<String, (MongoDatabase, Any?) -> Either<MongoData
 
 internal val dbDefaultConverter = unrecognizedField<MongoDatabase>("db options")
 
-internal val readConcernConverters: Map<String, (MongoDatabase, Any?) -> Either<MongoDatabase>> = mapOf(
-        typed("level", String::class.java) { db, value ->
-            db.withReadConcern(ReadConcern(ReadConcernLevel.fromString(value)))
-        }
-)
-
-internal val readConcernDefaultConverter = unrecognizedField<MongoDatabase>("read concern")
-
 internal fun <T> unrecognizedField(objectName: String): (T, String, Any?) -> Either<T> = { _, key, _ ->
     Left(CommandException("unrecognized $objectName field: $key", "FailedToParse"))
 }

packages/java-shell/src/test/resources/cursor/readConcern.expected.txt

@@ -1 +1,2 @@
-org.graalvm.polyglot.PolyglotException: Error: Setting readConcern on the cursor is not currently supported. See NODE-2806
+[ { "_id": <ObjectID>, "a": 1 } ]
+java.lang.IllegalArgumentException: 'unknown' is not a valid readConcernLevel

packages/java-shell/src/test/resources/cursor/readConcern-ignored.js renamed to packages/java-shell/src/test/resources/cursor/readConcern.js

@@ -3,5 +3,7 @@ db.coll.drop();
 db.coll.insertOne({a: 1});
 // command
 db.coll.find().readConcern('local');
+// command
+db.coll.find().readConcern('unknown');
 // clear
 db.coll.drop();