/*
* 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 com.facebook.presto.teradata.functions;
import com.facebook.presto.spi.ConnectorSession;
import com.facebook.presto.spi.PrestoException;
import com.facebook.presto.spi.function.Description;
import com.facebook.presto.spi.function.OperatorDependency;
import com.facebook.presto.spi.function.OperatorType;
import com.facebook.presto.spi.function.ScalarFunction;
import com.facebook.presto.spi.function.SqlType;
import com.facebook.presto.spi.type.StandardTypes;
import com.facebook.presto.spi.type.TimeZoneKey;
import io.airlift.concurrent.ThreadLocalCache;
import io.airlift.slice.Slice;
import org.joda.time.DateTimeZone;
import org.joda.time.chrono.ISOChronology;
import org.joda.time.format.DateTimeFormatter;
import java.lang.invoke.MethodHandle;
import static com.facebook.presto.spi.StandardErrorCode.GENERIC_INTERNAL_ERROR;
import static com.facebook.presto.spi.StandardErrorCode.INVALID_FUNCTION_ARGUMENT;
import static com.facebook.presto.spi.type.DateTimeEncoding.unpackMillisUtc;
import static com.facebook.presto.spi.type.DateTimeEncoding.unpackZoneKey;
import static com.facebook.presto.spi.type.TimeZoneKey.MAX_TIME_ZONE_KEY;
import static com.facebook.presto.spi.type.TimeZoneKey.getTimeZoneKeys;
import static com.facebook.presto.teradata.functions.dateformat.DateFormatParser.createDateTimeFormatter;
import static com.google.common.base.Throwables.propagateIfInstanceOf;
import static io.airlift.slice.Slices.utf8Slice;
import static java.nio.charset.StandardCharsets.UTF_8;
public final class TeradataDateFunctions
{
private static final ThreadLocalCache<Slice, DateTimeFormatter> DATETIME_FORMATTER_CACHE =
new ThreadLocalCache<>(100, format -> createDateTimeFormatter(format.toStringUtf8()));
private static final ISOChronology[] CHRONOLOGIES = new ISOChronology[MAX_TIME_ZONE_KEY + 1];
static {
for (TimeZoneKey timeZoneKey : getTimeZoneKeys()) {
DateTimeZone dateTimeZone = DateTimeZone.forID(timeZoneKey.getId());
CHRONOLOGIES[timeZoneKey.getKey()] = ISOChronology.getInstance(dateTimeZone);
}
}
private TeradataDateFunctions()
{
}
@Description("Formats a timestamp")
@ScalarFunction("to_char")
@SqlType(StandardTypes.VARCHAR)
public static Slice toChar(
ConnectorSession session,
@SqlType(StandardTypes.TIMESTAMP_WITH_TIME_ZONE) long timestampWithTimeZone,
@SqlType(StandardTypes.VARCHAR) Slice formatString)
{
DateTimeFormatter formatter = DATETIME_FORMATTER_CACHE.get(formatString)
.withChronology(CHRONOLOGIES[unpackZoneKey(timestampWithTimeZone).getKey()])
.withLocale(session.getLocale());
return utf8Slice(formatter.print(unpackMillisUtc(timestampWithTimeZone)));
}
@Description("Converts a string to a DATE data type")
@ScalarFunction("to_date")
@SqlType(StandardTypes.DATE)
public static long toDate(
@OperatorDependency(
operator = OperatorType.CAST,
returnType = StandardTypes.DATE,
argumentTypes = StandardTypes.TIMESTAMP)
MethodHandle castToDate,
ConnectorSession session,
@SqlType(StandardTypes.VARCHAR) Slice dateTime,
@SqlType(StandardTypes.VARCHAR) Slice formatString)
{
try {
long millis = parseMillis(session, dateTime, formatString);
return (long) castToDate.invokeExact(session, millis);
}
catch (Throwable t) {
propagateIfInstanceOf(t, Error.class);
propagateIfInstanceOf(t, PrestoException.class);
throw new PrestoException(GENERIC_INTERNAL_ERROR, t);
}
}
@Description("Converts a string to a TIMESTAMP data type")
@ScalarFunction("to_timestamp")
@SqlType(StandardTypes.TIMESTAMP)
public static long toTimestamp(
ConnectorSession session,
@SqlType(StandardTypes.VARCHAR) Slice dateTime,
@SqlType(StandardTypes.VARCHAR) Slice formatString)
{
return parseMillis(session, dateTime, formatString);
}
private static long parseMillis(ConnectorSession session, Slice dateTime, Slice formatString)
{
DateTimeFormatter formatter = DATETIME_FORMATTER_CACHE.get(formatString)
.withChronology(CHRONOLOGIES[session.getTimeZoneKey().getKey()])
.withLocale(session.getLocale());
try {
return formatter.parseMillis(dateTime.toString(UTF_8));
}
catch (IllegalArgumentException e) {
throw new PrestoException(INVALID_FUNCTION_ARGUMENT, e);
}
}
}