repl/src/main/scala/org/apache/livy/repl/Interpreter.scala

/*
 * 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.livy.repl

import org.json4s.JArray
import org.json4s.JObject

object Interpreter {
  abstract class ExecuteResponse

  case class ExecuteSuccess(content: JObject) extends ExecuteResponse
  case class ExecuteError(ename: String,
                          evalue: String,
                          traceback: Seq[String] = Seq()) extends ExecuteResponse
  case class ExecuteIncomplete() extends ExecuteResponse
  case class ExecuteAborted(message: String) extends ExecuteResponse
}

trait Interpreter {
  import Interpreter._

  def kind: String

  /**
   * Start the Interpreter.
   */
  def start(): Unit

  /**
   * Execute the code and return the result, it may
   * take some time to execute.
   */
  protected[repl] def execute(code: String): ExecuteResponse

  protected[repl] def complete(code: String, cursor: Int): Array[String]
    = Array()

  /** Shut down the interpreter. */
  def close(): Unit
}