org.apache.flink.table.planner.plan.nodes.exec.stream.StreamExecWindowTableFunction Maven / Gradle / Ivy

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 * 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,
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 * See the License for the specific language governing permissions and
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package org.apache.flink.table.planner.plan.nodes.exec.stream;

import org.apache.flink.api.dag.Transformation;
import org.apache.flink.table.data.RowData;
import org.apache.flink.table.planner.delegation.PlannerBase;
import org.apache.flink.table.planner.plan.logical.WindowingStrategy;
import org.apache.flink.table.planner.plan.nodes.exec.ExecEdge;
import org.apache.flink.table.planner.plan.nodes.exec.ExecNode;
import org.apache.flink.table.planner.plan.nodes.exec.ExecNodeBase;
import org.apache.flink.table.planner.plan.nodes.exec.InputProperty;
import org.apache.flink.table.types.logical.RowType;

import java.util.Collections;

/**
 * Stream {@link ExecNode} which acts as a table-valued function to assign a window for each row of
 * the input relation. The return value of the new relation includes all the original columns as
 * well additional 3 columns named {@code window_start}, {@code window_end}, {@code window_time} to
 * indicate the assigned window.
 */
public class StreamExecWindowTableFunction extends ExecNodeBase
        implements StreamExecNode {

    private final WindowingStrategy windowingStrategy;

    public StreamExecWindowTableFunction(
            WindowingStrategy windowingStrategy,
            InputProperty inputEdge,
            RowType outputType,
            String description) {
        super(Collections.singletonList(inputEdge), outputType, description);
        this.windowingStrategy = windowingStrategy;
    }

    @Override
    protected Transformation translateToPlanInternal(PlannerBase planner) {
        final ExecEdge inputEdge = getInputEdges().get(0);
        final RowType inputRowType = (RowType) inputEdge.getOutputType();
        String[] inputFieldNames = inputRowType.getFieldNames().toArray(new String[0]);
        String windowSummary = windowingStrategy.toSummaryString(inputFieldNames);

        throw new UnsupportedOperationException(
                String.format(
                        "Currently Flink doesn't support individual window table-valued function %s.\n "
                                + "Please use window table-valued function with aggregate together using window_start and window_end as group keys.",
                        windowSummary));
    }
}