| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License |
| */ |
| |
| package org.apache.toree.kernel.protocol.v5.stream |
| |
| import java.io.InputStream |
| import java.nio.charset.Charset |
| |
| import akka.pattern.ask |
| import org.apache.toree.kernel.protocol.v5.content.InputRequest |
| import org.apache.toree.kernel.protocol.v5.kernel.ActorLoader |
| import org.apache.toree.kernel.protocol.v5.kernel.Utilities.timeout |
| import org.apache.toree.kernel.protocol.v5.{KMBuilder, MessageType} |
| |
| import scala.collection.mutable.ListBuffer |
| import scala.concurrent.{Await, Future} |
| |
| import KernelInputStream._ |
| |
| object KernelInputStream { |
| val DefaultPrompt = "" |
| val DefaultPassword = false |
| } |
| |
| /** |
| * Represents an OutputStream that sends data back to the clients connect to the |
| * kernel instance. |
| * |
| * @param actorLoader The actor loader used to access the message relay |
| * @param kmBuilder The KMBuilder used to construct outgoing kernel messages |
| * @param prompt The prompt to use for input requests |
| * @param password Whether or not the input request is for a password |
| */ |
| class KernelInputStream( |
| actorLoader: ActorLoader, |
| kmBuilder: KMBuilder, |
| prompt: String = DefaultPrompt, |
| password: Boolean = DefaultPassword |
| ) extends InputStream { |
| private val EncodingType = Charset.forName("UTF-8") |
| @volatile private var internalBytes: ListBuffer[Byte] = ListBuffer() |
| |
| /** |
| * Returns the number of bytes available before the next request is made |
| * for more data. |
| * @return The total number of bytes in the internal buffer |
| */ |
| override def available(): Int = internalBytes.length |
| |
| /** |
| * Requests the next byte of data from the client. If the buffer containing |
| * @return The byte of data as an integer |
| */ |
| override def read(): Int = { |
| if (!this.hasByte) this.requestBytes() |
| |
| this.nextByte() |
| } |
| |
| private def hasByte: Boolean = internalBytes.nonEmpty |
| |
| private def nextByte(): Int = { |
| val byte = internalBytes.head |
| |
| internalBytes = internalBytes.tail |
| |
| byte |
| } |
| |
| private def requestBytes(): Unit = { |
| val inputRequest = InputRequest(prompt, password) |
| // NOTE: Assuming already provided parent header and correct ids |
| val kernelMessage = kmBuilder |
| .withHeader(MessageType.Outgoing.InputRequest) |
| .withContentString(inputRequest) |
| .build |
| |
| // NOTE: The same handler is being used in both request and reply |
| val responseFuture: Future[String] = |
| (actorLoader.load(MessageType.Incoming.InputReply) ? kernelMessage) |
| .mapTo[String] |
| |
| // Block until we get a response |
| import scala.concurrent.duration._ |
| internalBytes ++= |
| Await.result(responseFuture, Duration.Inf).getBytes(EncodingType) |
| } |
| } |