/*
* 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.ml;
import com.facebook.presto.ml.type.ClassifierType;
import com.facebook.presto.ml.type.RegressorType;
import com.facebook.presto.operator.scalar.ScalarFunction;
import com.facebook.presto.spi.type.StandardTypes;
import com.facebook.presto.type.SqlType;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.common.base.Throwables;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.hash.HashCode;
import io.airlift.slice.Slice;
import io.airlift.slice.Slices;
import java.util.HashMap;
import java.util.Map;
import static com.facebook.presto.ml.type.ClassifierType.CLASSIFIER;
import static com.facebook.presto.ml.type.RegressorType.REGRESSOR;
import static com.google.common.base.Preconditions.checkArgument;
public final class MLFunctions
{
private static final ObjectMapper OBJECT_MAPPER = new ObjectMapper();
private static final Cache<HashCode, Model> MODEL_CACHE = CacheBuilder.newBuilder().maximumSize(5).build();
private MLFunctions()
{
}
@ScalarFunction
@SqlType(StandardTypes.BIGINT)
public static long classify(@SqlType(StandardTypes.VARCHAR) Slice featuresMap, @SqlType(ClassifierType.NAME) Slice modelSlice)
{
FeatureVector features = ModelUtils.jsonToFeatures(featuresMap);
Model model = getOrLoadModel(modelSlice);
checkArgument(model instanceof Classifier && model.getType().equals(CLASSIFIER), "model is not a classifier");
return ((Classifier) model).classify(features);
}
@ScalarFunction
@SqlType(StandardTypes.DOUBLE)
public static double regress(@SqlType(StandardTypes.VARCHAR) Slice featuresMap, @SqlType(RegressorType.NAME) Slice modelSlice)
{
FeatureVector features = ModelUtils.jsonToFeatures(featuresMap);
Model model = getOrLoadModel(modelSlice);
checkArgument(model instanceof Regressor && model.getType().equals(REGRESSOR), "model is not a regressor");
return ((Regressor) model).regress(features);
}
private static Model getOrLoadModel(Slice slice)
{
HashCode modelHash = ModelUtils.modelHash(slice);
Model model = MODEL_CACHE.getIfPresent(modelHash);
if (model == null) {
model = ModelUtils.deserialize(slice);
MODEL_CACHE.put(modelHash, model);
}
return model;
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1)
{
return featuresHelper(f1);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2)
{
return featuresHelper(f1, f2);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3)
{
return featuresHelper(f1, f2, f3);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4)
{
return featuresHelper(f1, f2, f3, f4);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5)
{
return featuresHelper(f1, f2, f3, f4, f5);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6)
{
return featuresHelper(f1, f2, f3, f4, f5, f6);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7, @SqlType(StandardTypes.DOUBLE) double f8)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7, f8);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7, @SqlType(StandardTypes.DOUBLE) double f8, @SqlType(StandardTypes.DOUBLE) double f9)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7, f8, f9);
}
@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2, @SqlType(StandardTypes.DOUBLE) double f3, @SqlType(StandardTypes.DOUBLE) double f4, @SqlType(StandardTypes.DOUBLE) double f5, @SqlType(StandardTypes.DOUBLE) double f6, @SqlType(StandardTypes.DOUBLE) double f7, @SqlType(StandardTypes.DOUBLE) double f8, @SqlType(StandardTypes.DOUBLE) double f9, @SqlType(StandardTypes.DOUBLE) double f10)
{
return featuresHelper(f1, f2, f3, f4, f5, f6, f7, f8, f9, f10);
}
private static Slice featuresHelper(double... features)
{
Map<Integer, Double> featureMap = new HashMap<>();
for (int i = 0; i < features.length; i++) {
featureMap.put(i, features[i]);
}
try {
return Slices.utf8Slice(OBJECT_MAPPER.writeValueAsString(featureMap));
}
catch (JsonProcessingException e) {
throw Throwables.propagate(e);
}
}
}