SecondOrderFunctionTest.java

/***********************************************************************************************************************
 *
 * Copyright (C) 2010 by the Stratosphere project (http://stratosphere.eu)
 *
 * Licensed 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 eu.stratosphere.meteor.expression;

import org.junit.Assert;

import org.junit.Test;

import eu.stratosphere.meteor.MeteorTest;
import eu.stratosphere.sopremo.EvaluationContext;
import eu.stratosphere.sopremo.SecondOrderFunctions;
import eu.stratosphere.sopremo.base.Grouping;
import eu.stratosphere.sopremo.expressions.ArithmeticExpression;
import eu.stratosphere.sopremo.expressions.ArithmeticExpression.ArithmeticOperator;
import eu.stratosphere.sopremo.expressions.ArrayCreation;
import eu.stratosphere.sopremo.expressions.ConstantExpression;
import eu.stratosphere.sopremo.expressions.FunctionCall;
import eu.stratosphere.sopremo.expressions.InputSelection;
import eu.stratosphere.sopremo.expressions.ObjectCreation;
import eu.stratosphere.sopremo.function.ExpressionFunction;
import eu.stratosphere.sopremo.function.FunctionNode;
import eu.stratosphere.sopremo.function.JavaMethod;
import eu.stratosphere.sopremo.io.Sink;
import eu.stratosphere.sopremo.io.Source;
import eu.stratosphere.sopremo.operator.SopremoPlan;
import eu.stratosphere.sopremo.type.IJsonNode;
import eu.stratosphere.sopremo.type.JsonUtil;

/**
 */
public class SecondOrderFunctionTest extends MeteorTest {

	@Test
	public void testMapWithFunctionDefinition() {
		final SopremoPlan actualPlan = this.parseScript("square = fn(elem) { elem.a * elem.b };\n" +
			"$input = read from 'file://input.json';\n" +
			"$result = group $input by $input.key into { squared: map($input, &square) };\n" +
			"write $result to 'file://output.json'; ");

		final SopremoPlan expectedPlan = new SopremoPlan();
		final EvaluationContext context = expectedPlan.getEvaluationContext();
		context.getFunctionRegistry().put(SecondOrderFunctions.class);
		final ExpressionFunction squareFunction = new ExpressionFunction(1,
			new ArithmeticExpression(JsonUtil.createPath("0", "a"), ArithmeticOperator.MULTIPLICATION,
				JsonUtil.createPath("0", "b")));
		final ConstantExpression functionNode = new ConstantExpression(new FunctionNode(squareFunction));

		final Source input = new Source("file://input.json");
		final Grouping projection = new Grouping().
			withInputs(input).
			withGroupingKey(0, JsonUtil.createPath("0", "key")).
			withResultProjection(new ObjectCreation(
				new ObjectCreation.FieldAssignment("squared",
					new FunctionCall("map", context, new InputSelection(0), functionNode))));
		final Sink sink = new Sink("file://output.json").withInputs(projection);
		expectedPlan.setSinks(sink);

		Assert.assertEquals("unexpectedPlan", expectedPlan, actualPlan);
	}

	@Test
	public void testMapWithFunctionImport() throws SecurityException, NoSuchMethodException {
		final SopremoPlan actualPlan = this
			.parseScript("testudf = javaudf('" + this.getClass().getName() + ".udfTest');\n" +
				"$input = read from 'file://input.json';\n" +
				"$result = group $input by $input.key into map($input, &testudf);\n" +
				"write $result to 'file://output.json'; ");

		final SopremoPlan expectedPlan = new SopremoPlan();
		final EvaluationContext context = expectedPlan.getEvaluationContext();
		context.getFunctionRegistry().put(SecondOrderFunctions.class);
		final JavaMethod javaMethod = new JavaMethod("testudf");
		javaMethod.addSignature(this.getClass().getMethod("udfTest", IJsonNode[].class));
		final ConstantExpression functionNode = new ConstantExpression(new FunctionNode(javaMethod));

		final Source input = new Source("file://input.json");
		final Grouping projection = new Grouping().
			withInputs(input).
			withGroupingKey(0, JsonUtil.createPath("0", "key")).
			withResultProjection(new FunctionCall("map", context, new InputSelection(0), functionNode));
		final Sink sink = new Sink("file://output.json").withInputs(projection);
		expectedPlan.setSinks(sink);

		Assert.assertEquals("unexpectedPlan", expectedPlan, actualPlan);
	}

	@Test
	public void testMapWithInlineFunction() {
		final SopremoPlan actualPlan = this.parseScript(
			"$input = read from 'file://input.json';\n" +
				"$result = group $input by $input.key into [map($input, fn(elem) { elem.a * elem.b })];\n" +
				"write $result to 'file://output.json'; ");

		final SopremoPlan expectedPlan = new SopremoPlan();
		final EvaluationContext context = expectedPlan.getEvaluationContext();
		context.getFunctionRegistry().put(SecondOrderFunctions.class);
		final ExpressionFunction squareFunction = new ExpressionFunction(1,
			new ArithmeticExpression(JsonUtil.createPath("0", "a"), ArithmeticOperator.MULTIPLICATION,
				JsonUtil.createPath("0", "b")));
		final ConstantExpression functionNode = new ConstantExpression(new FunctionNode(squareFunction));

		final Source input = new Source("file://input.json");
		final Grouping projection = new Grouping().
			withInputs(input).
			withGroupingKey(0, JsonUtil.createPath("0", "key")).
			withResultProjection(new ArrayCreation(
				new FunctionCall("map", context, new InputSelection(0), functionNode)));
		final Sink sink = new Sink("file://output.json").withInputs(projection);
		expectedPlan.setSinks(sink);

		Assert.assertEquals("unexpectedPlan", expectedPlan, actualPlan);
	}

	public static IJsonNode udfTest(final IJsonNode... nodes) {
		return nodes[0];
	}
}