/*
* Copyright 2014 the original author or authors.
*
* 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 ratpack.jackson.configuration.internal;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.fasterxml.jackson.databind.node.TreeTraversingParser;
import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
import com.fasterxml.jackson.dataformat.yaml.YAMLParser;
import com.fasterxml.jackson.datatype.guava.GuavaModule;
import com.google.common.io.ByteSource;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import ratpack.configuration.Configuration;
import ratpack.configuration.ConfigurationException;
import ratpack.configuration.ConfigurationFactory;
import ratpack.configuration.ConfigurationSource;
import javax.validation.ConstraintViolation;
import javax.validation.Validation;
import javax.validation.ValidationException;
import javax.validation.Validator;
import java.io.IOException;
import java.io.InputStream;
import java.util.Set;
public class JacksonConfigurationFactory implements ConfigurationFactory {
private static final Logger LOGGER = LoggerFactory.getLogger(JacksonConfigurationFactory.class);
private final YAMLFactory yamlFactory = new YAMLFactory();
private final Validator validator = buildValidator();
private final ObjectMapper objectMapper = buildObjectMapper();
@Override
public <T extends Configuration> T build(Class<T> configurationClass, ConfigurationSource configurationSource) throws ConfigurationException {
ObjectNode node;
ByteSource byteSource = configurationSource.getByteSource();
try {
if (byteSource.isEmpty()) {
node = JsonNodeFactory.instance.objectNode();
} else {
try (InputStream inputStream = configurationSource.getByteSource().openBufferedStream()) {
YAMLParser yamlParser = yamlFactory.createParser(inputStream);
node = objectMapper.readTree(yamlParser);
}
}
return build(configurationClass, node);
} catch (IOException ex) {
throw new ConfigurationException("Failed to load configuration", ex);
}
}
private <T extends Configuration> T build(Class<T> configurationClass, ObjectNode node) throws IOException, ConfigurationException {
// TODO: property overrides
// TODO: environment overrides
T configuration = objectMapper.readValue(new TreeTraversingParser(node), configurationClass);
if (validator != null) {
Set<ConstraintViolation<T>> violations = validator.validate(configuration);
if (!violations.isEmpty()) {
throw new ConfigurationException("Configuration failed validation: " + violations.toString());
}
}
return configuration;
}
private static Validator buildValidator() {
try {
return Validation.buildDefaultValidatorFactory().getValidator();
} catch (ValidationException ex) {
LOGGER.warn("Could not load a validation provider");
LOGGER.debug("", ex);
return null;
}
}
private static ObjectMapper buildObjectMapper() {
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.registerModule(new GuavaModule());
objectMapper.setSubtypeResolver(new DiscoverableSubtypeResolver());
return objectMapper;
}
}