io.druid.query.expression.TimestampExtractExprMacro.java Source code

Introduction

Here is the source code for io.druid.query.expression.TimestampExtractExprMacro.java

Source

/*
 * Licensed to Metamarkets Group Inc. (Metamarkets) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. Metamarkets 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 io.druid.query.expression;

import io.druid.java.util.common.IAE;
import io.druid.java.util.common.ISE;
import io.druid.math.expr.Expr;
import io.druid.math.expr.ExprEval;
import io.druid.math.expr.ExprMacroTable;
import org.joda.time.DateTime;
import org.joda.time.DateTimeZone;
import org.joda.time.chrono.ISOChronology;

import javax.annotation.Nonnull;
import java.util.List;

public class TimestampExtractExprMacro implements ExprMacroTable.ExprMacro {
    public enum Unit {
        EPOCH, SECOND, MINUTE, HOUR, DAY, DOW, DOY, WEEK, MONTH, QUARTER, YEAR
    }

    @Override
    public String name() {
        return "timestamp_extract";
    }

    @Override
    public Expr apply(final List<Expr> args) {
        if (args.size() < 2 || args.size() > 3) {
            throw new IAE("Function[%s] must have 2 to 3 arguments", name());
        }

        if (!args.get(1).isLiteral() || args.get(1).getLiteralValue() == null) {
            throw new IAE("Function[%s] unit arg must be literal", name());
        }

        if (args.size() > 2 && !args.get(2).isLiteral()) {
            throw new IAE("Function[%s] timezone arg must be literal", name());
        }

        final Expr arg = args.get(0);
        final Unit unit = Unit.valueOf(((String) args.get(1).getLiteralValue()).toUpperCase());
        final DateTimeZone timeZone;

        if (args.size() > 2) {
            timeZone = ExprUtils.toTimeZone(args.get(2));
        } else {
            timeZone = DateTimeZone.UTC;
        }

        final ISOChronology chronology = ISOChronology.getInstance(timeZone);

        class TimestampExtractExpr implements Expr {
            @Nonnull
            @Override
            public ExprEval eval(final ObjectBinding bindings) {
                final DateTime dateTime = new DateTime(arg.eval(bindings).asLong()).withChronology(chronology);
                switch (unit) {
                case EPOCH:
                    return ExprEval.of(dateTime.getMillis());
                case SECOND:
                    return ExprEval.of(dateTime.secondOfMinute().get());
                case MINUTE:
                    return ExprEval.of(dateTime.minuteOfHour().get());
                case HOUR:
                    return ExprEval.of(dateTime.hourOfDay().get());
                case DAY:
                    return ExprEval.of(dateTime.dayOfMonth().get());
                case DOW:
                    return ExprEval.of(dateTime.dayOfWeek().get());
                case DOY:
                    return ExprEval.of(dateTime.dayOfYear().get());
                case WEEK:
                    return ExprEval.of(dateTime.weekOfWeekyear().get());
                case MONTH:
                    return ExprEval.of(dateTime.monthOfYear().get());
                case QUARTER:
                    return ExprEval.of((dateTime.monthOfYear().get() - 1) / 3 + 1);
                case YEAR:
                    return ExprEval.of(dateTime.year().get());
                default:
                    throw new ISE("Unhandled unit[%s]", unit);
                }
            }

            @Override
            public void visit(final Visitor visitor) {
                arg.visit(visitor);
                visitor.visit(this);
            }
        }

        return new TimestampExtractExpr();
    }
}