ai.djl.translate.DeferredTranslatorFactory Maven / Gradle / Ivy
/*
* Copyright 2022 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except in compliance
* with the License. A copy of the License is located at
*
* http://aws.amazon.com/apache2.0/
*
* or in the "license" file accompanying this file. This file 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 ai.djl.translate;
import ai.djl.Model;
import ai.djl.repository.zoo.Criteria;
import ai.djl.util.Pair;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.lang.reflect.Constructor;
import java.lang.reflect.Type;
import java.util.Collections;
import java.util.Map;
import java.util.Set;
/**
* A {@link TranslatorFactory} that creates the {@link Translator} based on serving.properties file.
*
* The {@link Criteria} API cannot access serving.properties files before it's downloaded. A
* {@code DeferredTranslatorFactory} assumes serving.properties will provide proper {@link
* Translator}. If no translatorFactory is provided in serving.properties, a {@link
* TranslateException} will be thrown.
*/
public class DeferredTranslatorFactory implements TranslatorFactory {
private static final Logger logger = LoggerFactory.getLogger(DeferredTranslatorFactory.class);
/** {@inheritDoc} */
@Override
public Set> getSupportedTypes() {
return Collections.emptySet();
}
/** {@inheritDoc} */
@Override
public boolean isSupported(Class input, Class output) {
return true;
}
/** {@inheritDoc} */
@Override
public Translator newInstance(
Class input, Class output, Model model, Map arguments)
throws TranslateException {
String factoryClass = ArgumentsUtil.stringValue(arguments, "translatorFactory");
if (factoryClass == null || factoryClass.isEmpty()) {
throw new TranslateException("No translatorFactory defined.");
}
TranslatorFactory factory = loadTranslatorFactory(factoryClass);
if (factory == null) {
throw new TranslateException("Failed to load translatorFactory: " + factoryClass);
} else if (!factory.isSupported(input, output)) {
throw new TranslateException(factoryClass + " doesn't support Input/Output.");
}
logger.info("Using TranslatorFactory: {}", factoryClass);
return factory.newInstance(input, output, model, arguments);
}
private TranslatorFactory loadTranslatorFactory(String className) {
try {
Class clazz = Class.forName(className);
Class subclass = clazz.asSubclass(TranslatorFactory.class);
Constructor constructor = subclass.getConstructor();
return constructor.newInstance();
} catch (Throwable e) {
logger.trace("Not able to load TranslatorFactory: {}", className, e);
}
return null;
}
}