| /* |
| * 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.calcite.adapter.druid; |
| |
| import com.fasterxml.jackson.core.JsonGenerator; |
| |
| import java.io.IOException; |
| import java.util.Objects; |
| import javax.annotation.Nullable; |
| |
| import static org.apache.calcite.adapter.druid.DruidQuery.writeField; |
| import static org.apache.calcite.adapter.druid.DruidQuery.writeFieldIf; |
| import static org.apache.calcite.util.DateTimeStringUtils.ISO_DATETIME_FRACTIONAL_SECOND_FORMAT; |
| |
| /** |
| * Implementation of extraction function DimensionSpec. |
| * |
| * <p>The extraction function implementation returns dimension values transformed |
| * using the given extraction function. |
| */ |
| public class ExtractionDimensionSpec implements DimensionSpec { |
| private final String dimension; |
| private final ExtractionFunction extractionFunction; |
| private final String outputName; |
| private final DruidType outputType; |
| |
| public ExtractionDimensionSpec(String dimension, ExtractionFunction extractionFunction, |
| String outputName) { |
| this(dimension, extractionFunction, outputName, DruidType.STRING); |
| } |
| |
| public ExtractionDimensionSpec(String dimension, ExtractionFunction extractionFunction, |
| String outputName, DruidType outputType) { |
| this.dimension = Objects.requireNonNull(dimension); |
| this.extractionFunction = Objects.requireNonNull(extractionFunction); |
| this.outputName = outputName; |
| this.outputType = outputType == null ? DruidType.STRING : outputType; |
| } |
| |
| @Override public String getOutputName() { |
| return outputName; |
| } |
| |
| @Override public DruidType getOutputType() { |
| return outputType; |
| } |
| |
| @Override public ExtractionFunction getExtractionFn() { |
| return extractionFunction; |
| } |
| |
| @Override public String getDimension() { |
| return dimension; |
| } |
| |
| @Override public void write(JsonGenerator generator) throws IOException { |
| generator.writeStartObject(); |
| generator.writeStringField("type", "extraction"); |
| generator.writeStringField("dimension", dimension); |
| writeFieldIf(generator, "outputName", outputName); |
| writeField(generator, "extractionFn", extractionFunction); |
| generator.writeEndObject(); |
| } |
| |
| /** Returns a valid {@link Granularity} of floor extract, or null when not |
| * possible. |
| * |
| * @param dimensionSpec Druid Dimension specification |
| */ |
| @Nullable |
| public static Granularity toQueryGranularity(DimensionSpec dimensionSpec) { |
| if (!DruidTable.DEFAULT_TIMESTAMP_COLUMN.equals(dimensionSpec.getDimension())) { |
| // Only __time column can be substituted by granularity |
| return null; |
| } |
| final ExtractionFunction extractionFunction = dimensionSpec.getExtractionFn(); |
| if (extractionFunction == null) { |
| // No Extract thus no Granularity |
| return null; |
| } |
| if (extractionFunction instanceof TimeExtractionFunction) { |
| Granularity granularity = ((TimeExtractionFunction) extractionFunction).getGranularity(); |
| String format = ((TimeExtractionFunction) extractionFunction).getFormat(); |
| if (!ISO_DATETIME_FRACTIONAL_SECOND_FORMAT.equals(format)) { |
| return null; |
| } |
| return granularity; |
| } |
| return null; |
| } |
| |
| } |