/*
* Copyright 2012-2014 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 org.springframework.data.rest.core.event;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.ObjectFactory;
import org.springframework.data.repository.support.Repositories;
import org.springframework.data.rest.core.RepositoryConstraintViolationException;
import org.springframework.data.rest.core.ValidationErrors;
import org.springframework.util.Assert;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator;
/**
* {@link org.springframework.context.ApplicationListener} implementation that dispatches {@link RepositoryEvent}s to a
* specific {@link Validator}.
*
* @author Jon Brisbin
* @author Oliver Gierke
*/
public class ValidatingRepositoryEventListener extends AbstractRepositoryEventListener<Object> {
private static final Logger LOGGER = LoggerFactory.getLogger(ValidatingRepositoryEventListener.class);
private final ObjectFactory<Repositories> repositoriesFactory;
private final MultiValueMap<String, Validator> validators;
/**
* Creates a new {@link ValidatingRepositoryEventListener} using the given repositories.
*
* @param repositoriesFactory must not be {@literal null}.
*/
public ValidatingRepositoryEventListener(ObjectFactory<Repositories> repositoriesFactory) {
Assert.notNull(repositoriesFactory, "Repositories must not be null!");
this.repositoriesFactory = repositoriesFactory;
this.validators = new LinkedMultiValueMap<String, Validator>();
}
/**
* Assign a Map of {@link Validator}s that are assigned to the various {@link RepositoryEvent}s.
*
* @param validators A Map of Validators to wire.
* @return @this
*/
public ValidatingRepositoryEventListener setValidators(Map<String, Collection<Validator>> validators) {
for (Map.Entry<String, Collection<Validator>> entry : validators.entrySet()) {
this.validators.put(entry.getKey(), new ArrayList<Validator>(entry.getValue()));
}
return this;
}
/**
* Add a {@link Validator} that will be triggered on the given event.
*
* @param event The event to listen for.
* @param validator The Validator to execute when that event fires.
* @return @this
*/
public ValidatingRepositoryEventListener addValidator(String event, Validator validator) {
validators.add(event, validator);
return this;
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onBeforeCreate(java.lang.Object)
*/
@Override
protected void onBeforeCreate(Object entity) {
validate("beforeCreate", entity);
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onAfterCreate(java.lang.Object)
*/
@Override
protected void onAfterCreate(Object entity) {
validate("afterCreate", entity);
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onBeforeSave(java.lang.Object)
*/
@Override
protected void onBeforeSave(Object entity) {
validate("beforeSave", entity);
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onAfterSave(java.lang.Object)
*/
@Override
protected void onAfterSave(Object entity) {
validate("afterSave", entity);
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onBeforeLinkSave(java.lang.Object, java.lang.Object)
*/
@Override
protected void onBeforeLinkSave(Object parent, Object linked) {
validate("beforeLinkSave", parent);
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onAfterLinkSave(java.lang.Object, java.lang.Object)
*/
@Override
protected void onAfterLinkSave(Object parent, Object linked) {
validate("afterLinkSave", parent);
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onBeforeDelete(java.lang.Object)
*/
@Override
protected void onBeforeDelete(Object entity) {
validate("beforeDelete", entity);
}
/*
* (non-Javadoc)
* @see org.springframework.data.rest.core.event.AbstractRepositoryEventListener#onAfterDelete(java.lang.Object)
*/
@Override
protected void onAfterDelete(Object entity) {
validate("afterDelete", entity);
}
private Errors validate(String event, Object o) {
if (o == null) {
return null;
}
Class<?> domainType = o.getClass();
Repositories repositories = repositoriesFactory.getObject();
Errors errors = new ValidationErrors(domainType.getSimpleName(), o, repositories.getPersistentEntity(domainType));
for (Validator v : getValidatorsForEvent(event)) {
if (v.supports(domainType)) {
LOGGER.debug("{}: {} with {}", event, o, v);
ValidationUtils.invokeValidator(v, o, errors);
}
}
if (errors.getErrorCount() > 0) {
throw new RepositoryConstraintViolationException(errors);
}
return errors;
}
private Collection<Validator> getValidatorsForEvent(String event) {
Collection<Validator> validators = this.validators.get(event);
return validators == null ? Collections.<Validator> emptySet() : validators;
}
}