Add a unit test for Flink SQL

Question

I am using Flink v1.7.1. When I finished a Flink streaming job with tableSource, SQL and tableSink, I have no idea how to add a unit test for it.

Answer 1

I found a good example about how to testing flink sql with the help of user mailing list, here is a example.

package org.apache.flink.table.runtime.stream.sql;

import org.apache.flink.api.common.typeinfo.BasicTypeInfo;
import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.java.tuple.Tuple3;
import org.apache.flink.api.java.tuple.Tuple5;
import org.apache.flink.api.java.typeutils.RowTypeInfo;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.Table;
import org.apache.flink.table.api.TableEnvironment;
import org.apache.flink.table.api.java.StreamTableEnvironment;
import org.apache.flink.table.runtime.utils.JavaStreamTestData;
import org.apache.flink.table.runtime.utils.StreamITCase;
import org.apache.flink.test.util.AbstractTestBase;
import org.apache.flink.types.Row;

import org.junit.Test;

import java.util.ArrayList;
import java.util.List;

/**
 * Integration tests for streaming SQL.
 */
public class JavaSqlITCase extends AbstractTestBase {

    @Test
    public void testRowRegisterRowWithNames() throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        StreamTableEnvironment tableEnv = TableEnvironment.getTableEnvironment(env);
        StreamITCase.clear();

        List<Row> data = new ArrayList<>();
        data.add(Row.of(1, 1L, "Hi"));
        data.add(Row.of(2, 2L, "Hello"));
        data.add(Row.of(3, 2L, "Hello world"));

        TypeInformation<?>[] types = {
                BasicTypeInfo.INT_TYPE_INFO,
                BasicTypeInfo.LONG_TYPE_INFO,
                BasicTypeInfo.STRING_TYPE_INFO};
        String[] names = {"a", "b", "c"};

        RowTypeInfo typeInfo = new RowTypeInfo(types, names);

        DataStream<Row> ds = env.fromCollection(data).returns(typeInfo);

        Table in = tableEnv.fromDataStream(ds, "a,b,c");
        tableEnv.registerTable("MyTableRow", in);

        String sqlQuery = "SELECT a,c FROM MyTableRow";
        Table result = tableEnv.sqlQuery(sqlQuery);

        DataStream<Row> resultSet = tableEnv.toAppendStream(result, Row.class);
        resultSet.addSink(new StreamITCase.StringSink<Row>());
        env.execute();

        List<String> expected = new ArrayList<>();
        expected.add("1,Hi");
        expected.add("2,Hello");
        expected.add("3,Hello world");

        StreamITCase.compareWithList(expected);
    }
}

the related code is here