Java fixes, cursor methods and tests

packages/java-shell/build.gradle

@@ -28,7 +28,7 @@ compileJava.dependsOn browserifyShellApi
 dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
     testCompile group: 'junit', name: 'junit', version: '4.12'
-    compile group: 'org.graalvm.js', name: 'js', version: '20.0.0'
+    compile group: 'org.graalvm.js', name: 'js', version: '20.2.0'
     compile group: 'org.mongodb', name: 'mongo-java-driver', version: '3.12.7'
     compile group: 'org.apache.commons', name: 'commons-text', version: '1.8'
 }

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

@@ -2,9 +2,8 @@ package com.mongodb.mongosh
 
 import com.mongodb.client.MongoClient
 import com.mongodb.mongosh.result.MongoShellResult
-import java.io.Closeable
 
-class MongoShell(client: MongoClient) : Closeable {
+class MongoShell(client: MongoClient) {
     private val context = MongoShellContext(client)
 
     fun eval(script: String): MongoShellResult<*> {
@@ -14,5 +13,5 @@ class MongoShell(client: MongoClient) : Closeable {
         return context.extract(value, if (type.isString) type.asString() else null)
     }
 
-    override fun close() = context.close()
+    fun close() = context.close()
 }

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

@@ -16,7 +16,7 @@ import org.graalvm.polyglot.Source
 import org.graalvm.polyglot.Value
 import org.graalvm.polyglot.proxy.ProxyExecutable
 import org.intellij.lang.annotations.Language
-import java.io.Closeable
+import java.lang.IllegalStateException
 import java.time.LocalDateTime
 import java.time.ZoneOffset
 import java.time.format.DateTimeFormatter
@@ -31,8 +31,8 @@ import java.util.concurrent.ExecutionException
 import java.util.concurrent.TimeUnit
 import java.util.regex.Pattern
 
-internal class MongoShellContext(client: MongoClient) : Closeable {
-    val ctx: Context = Context.create()
+internal class MongoShellContext(client: MongoClient) {
+    private var ctx: Context? = Context.create()
     private val serviceProvider = JavaServiceProvider(client, this)
     private val shellEvaluator: Value
     private val bsonTypes: BsonTypes
@@ -44,6 +44,7 @@ internal class MongoShellContext(client: MongoClient) : Closeable {
     init {
         val setupScript = MongoShell::class.java.getResource("/js/all-standalone.js").readText()
         evalInner(setupScript, "all-standalone.js")
+        val ctx = checkClosed()
         val context = ctx.getBindings("js")
         val global = context["_global"]!!
         context.removeMember("_global")
@@ -76,6 +77,7 @@ internal class MongoShellContext(client: MongoClient) : Closeable {
         context.putMember("Date", date)
         val isoDate = functionProducer.execute(ProxyExecutable { args -> dateHelper(true, args.toList()) })
         context.putMember("ISODate", isoDate)
+        context.putMember("UUID", functionProducer.execute(ProxyExecutable { args -> if (args.isEmpty()) UUID.randomUUID() else UUID.fromString(args[0].asString()) }))
     }
 
     private fun dateHelper(createObject: Boolean, args: List<Value>): Any {
@@ -124,9 +126,14 @@ internal class MongoShellContext(client: MongoClient) : Closeable {
     }
 
     operator fun get(value: String): Value? {
+        val ctx = checkClosed()
         return ctx.getBindings("js")[value]
     }
 
+    private fun checkClosed(): Context {
+        return this.ctx ?: throw IllegalStateException("Context has already been closed")
+    }
+
     internal operator fun Value.get(identifier: String): Value? {
         return getMember(identifier)
     }
@@ -158,7 +165,8 @@ internal class MongoShellContext(client: MongoClient) : Closeable {
             v.instanceOf("Promise") -> extract(unwrapPromise(v))
             type == "Help" -> extract(v["attr"]!!)
             type == "Cursor" -> FindCursorResult(FindCursor<Any?>(v, this))
-            type == "AggregationCursor" -> AggregationCursorResult(AggregationCursor<Any?>(v, this))
+            // document with aggregation explain result also has type AggregationCursor, so we need to make sure that value contains cursor
+            type == "AggregationCursor" && v.hasMember("_cursor") -> AggregationCursorResult(AggregationCursor<Any?>(v, this))
             type == "InsertOneResult" -> InsertOneResult(v["acknowledged"]!!.asBoolean(), v["insertedId"]!!.asString())
             type == "DeleteResult" -> DeleteResult(v["acknowledged"]!!.asBoolean(), v["deletedCount"]!!.asLong())
             type == "UpdateResult" -> {
@@ -240,6 +248,7 @@ internal class MongoShellContext(client: MongoClient) : Closeable {
     }
 
     private fun evalInner(@Language("js") script: String, name: String = "Unnamed"): Value {
+        val ctx = checkClosed()
         return ctx.eval(Source.newBuilder("js", script, name).buildLiteral())
     }
 
@@ -257,7 +266,11 @@ internal class MongoShellContext(client: MongoClient) : Closeable {
         }
     }
 
-    override fun close() = serviceProvider.close()
+    fun close() {
+        val ctx = checkClosed()
+        ctx.close(true)
+        this.ctx = null
+    }
 
     private fun Value.instanceOf(clazz: Value?): Boolean {
         return clazz != null && evalInner("(o, clazz) => o instanceof clazz", "instance_of_class_script").execute(this, clazz).asBoolean()

packages/java-shell/src/main/kotlin/com/mongodb/mongosh/result/AggregationCursor.kt

@@ -1,20 +1,36 @@
 package com.mongodb.mongosh.result
 
 import com.mongodb.mongosh.MongoShellContext
-import org.bson.Document
 import org.graalvm.polyglot.Value
 
-class AggregationCursor<out T> internal constructor(private val cursor: Value, private val context: MongoShellContext) : Cursor<T> {
+class AggregationCursor<out T> internal constructor(private var cursor: Value?, private var context: MongoShellContext?) : Cursor<T> {
     override fun hasNext(): Boolean {
+        val (cursor, _) = checkClosed()
         return cursor.invokeMember("hasNext").asBoolean()
     }
 
     override fun next(): T {
+        val (cursor, context) = checkClosed()
         if (!hasNext()) throw NoSuchElementException()
         return context.extract(cursor.invokeMember("next")).value as T
     }
 
     override fun _asPrintable(): String {
+        val (cursor, context) = checkClosed()
         return context.extract(cursor.invokeMember("_asPrintable"))._asPrintable()
     }
+
+    override fun close() {
+        val (c, _) = checkClosed()
+        c.invokeMember("close")
+        cursor = null
+        context = null
+    }
+
+    private fun checkClosed(): Pair<Value, MongoShellContext> {
+        val cursor = this.cursor
+        val context = this.context
+        if (cursor == null || context == null) throw IllegalStateException("Cursor has already been closed")
+        return cursor to context
+    }
 }

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

@@ -2,4 +2,5 @@ package com.mongodb.mongosh.result
 
 interface Cursor<out T> : Iterator<T> {
     fun _asPrintable(): String
+    fun close()
 }

packages/java-shell/src/main/kotlin/com/mongodb/mongosh/result/FindCursor.kt

@@ -1,24 +1,41 @@
 package com.mongodb.mongosh.result
 
 import com.mongodb.mongosh.MongoShellContext
-import org.bson.Document
 import org.graalvm.polyglot.Value
 
-class FindCursor<out T> internal constructor(private val cursor: Value, private val context: MongoShellContext) : Cursor<T> {
+class FindCursor<out T> internal constructor(private var cursor: Value?, private var context: MongoShellContext?) : Cursor<T> {
     override fun hasNext(): Boolean {
+        val (cursor, _) = checkClosed()
         return cursor.invokeMember("hasNext").asBoolean()
     }
 
     override fun next(): T {
+        val (cursor, context) = checkClosed()
         if (!hasNext()) throw NoSuchElementException()
         return context.extract(cursor.invokeMember("next")).value as T
     }
 
     fun batchSize(size: Int) {
+        val (cursor, _) = checkClosed()
         cursor.invokeMember("batchSize", size)
     }
 
     override fun _asPrintable(): String {
+        val (cursor, context) = checkClosed()
         return context.extract(cursor.invokeMember("_asPrintable"))._asPrintable()
     }
+
+    override fun close() {
+        val (c, _) = checkClosed()
+        c.invokeMember("close")
+        cursor = null
+        context = null
+    }
+
+    private fun checkClosed(): Pair<Value, MongoShellContext> {
+        val cursor = this.cursor
+        val context = this.context
+        if (cursor == null || context == null) throw IllegalStateException("Cursor has already been closed")
+        return cursor to context
+    }
 }

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

@@ -0,0 +1,10 @@
+package com.mongodb.mongosh.service
+
+import org.graalvm.polyglot.Value
+
+/**
+ * see service-provider-core/src/admin.ts
+ */
+internal interface AdminServiceProvider {
+    fun createCollection(database: String, collection: String, options: Value?): Value
+}

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

@@ -1,7 +1,6 @@
 package com.mongodb.mongosh.service
 
 import com.mongodb.client.MongoCursor
-import com.mongodb.client.model.Collation
 import com.mongodb.mongosh.MongoShellContext
 import com.mongodb.mongosh.result.DocumentResult
 import org.bson.Document
@@ -56,7 +55,7 @@ internal class Cursor(private var helper: MongoIterableHelper<*>, private val co
     @HostAccess.Export
     override fun close() {
         closed = true
-        getOrCreateIterator().close()
+        iterator?.close()
     }
 
     @HostAccess.Export
@@ -76,9 +75,7 @@ internal class Cursor(private var helper: MongoIterableHelper<*>, private val co
         if (!v.hasMembers()) {
             throw IllegalArgumentException("Expected one argument of type object. Got: $v")
         }
-        val collation = convert(Collation.builder(), collationConverters, collationDefaultConverter, toDocument(context, v))
-                .getOrThrow()
-                .build()
+        val collation = toDocument(context, v)
         helper.collation(collation)
         return this
     }
@@ -97,8 +94,9 @@ internal class Cursor(private var helper: MongoIterableHelper<*>, private val co
     }
 
     @HostAccess.Export
-    override fun explain(verbosity: String) {
-        throw NotImplementedError("explain is not supported")
+    override fun explain(verbosity: String?): Any? {
+        checkQueryNotExecuted()
+        return context.toJs(helper.explain(verbosity))
     }
 
     @HostAccess.Export
@@ -205,9 +203,10 @@ internal class Cursor(private var helper: MongoIterableHelper<*>, private val co
     }
 
     @HostAccess.Export
-    override fun setReadPreference(v: Value): Cursor {
+    override fun setReadPreference(v: String): Cursor {
         checkQueryNotExecuted()
-        throw NotImplementedError("setReadPreference is not supported")
+        helper = helper.readPrev(v, null)
+        return this
     }
 
     override fun showRecordId(v: Boolean): ServiceProviderCursor {