flink-end-to-end-tests/flink-python-test/src/main/java/org/apache/flink/python/tests/FlinkBatchPythonUdfSqlJob.java

/*
 * 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.flink.python.tests;

import org.apache.flink.api.java.ExecutionEnvironment;
import org.apache.flink.table.api.bridge.java.BatchTableEnvironment;
import org.apache.flink.types.Row;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

/** A simple job used to test submitting the Python UDF job in flink batch mode. */
public class FlinkBatchPythonUdfSqlJob {

    public static void main(String[] args) {
        ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
        env.setParallelism(1);
        BatchTableEnvironment tEnv = BatchTableEnvironment.create(env);
        tEnv.executeSql(
                "create temporary system function add_one as 'add_one.add_one' language python");

        tEnv.createTemporaryView("source", tEnv.fromDataSet(env.fromElements(1L, 2L, 3L)).as("a"));

        Iterator<Row> result = tEnv.executeSql("select add_one(a) as a from source").collect();

        List<Long> actual = new ArrayList<>();
        while (result.hasNext()) {
            Row r = result.next();
            actual.add((Long) r.getField(0));
        }

        List<Long> expected = Arrays.asList(2L, 3L, 4L);
        if (!actual.equals(expected)) {
            throw new AssertionError(
                    String.format(
                            "The output result: %s is not as expected: %s!", actual, expected));
        }
    }
}