/**
* JBoss, Home of Professional Open Source
* Copyright Red Hat, Inc., and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* 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.jboss.aerogear.controller.router;
import static org.jboss.aerogear.controller.util.ParameterExtractor.extractArguments;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import javax.enterprise.inject.Instance;
import javax.enterprise.inject.spi.BeanManager;
import javax.inject.Inject;
import org.jboss.aerogear.controller.router.rest.pagination.Paginated;
import org.jboss.aerogear.controller.router.rest.pagination.Pagination;
import org.jboss.aerogear.controller.router.rest.pagination.PaginationInfo;
import org.jboss.aerogear.controller.router.rest.pagination.PagingStrategy;
/**
* Default implementation of {@link RouteProcessor}.
* </p>
* This implementation uses Context and Dependency Injection (CDI) to have various parts injected into it. Of<br>
* particular interest for end users is the {@link RoutingModule} which is described in more detail in the section below.
*
* <h3> RoutingModule </h3>
* The CDI implementation will scan for an instance of {@link RoutingModule} upon deployment, and its<br>
* {@link RoutingModule#build()} method will be called to assemble the routes configured for this application.<br>
* To simplify this process {@link AbstractRoutingModule} is provided, please refer its javadoc for sample usage.
*/
public class DefaultRouteProcessor implements RouteProcessor {
private BeanManager beanManager;
private ControllerFactory controllerFactory;
private Responders responders;
private final Map<String, Consumer> consumers = new HashMap<String, Consumer>();
public DefaultRouteProcessor() {
}
@Inject
public DefaultRouteProcessor(BeanManager beanManager, Instance<Consumer> consumers, Responders responders, ControllerFactory controllerFactory) {
this.beanManager = beanManager;
this.controllerFactory = controllerFactory;
this.responders = responders;
for (Consumer consumer : consumers) {
this.consumers.put(consumer.mediaType(), consumer);
}
}
@Override
public void process(RouteContext routeContext) throws Exception {
final Route route = routeContext.getRoute();
final Map<String, Object> arguments = extractArguments(routeContext, consumers);
if (hasPaginatedAnnotation(route.getTargetMethod())) {
processPaged(routeContext, arguments);
} else {
responders.respond(routeContext, route.getTargetMethod().invoke(getController(route), arguments.values().toArray()));
}
}
private void processPaged(RouteContext routeContext, Map<String, Object> arguments) throws Exception {
final Route route = routeContext.getRoute();
final PagingStrategy pagingStrategy = getPagingStrategy(route, arguments);
final PaginationInfo paginationInfo = pagingStrategy.getPaginationInfo();
final List<Object> pagingArgs = merge(paginationInfo, arguments);
final Object result = route.getTargetMethod().invoke(getController(route), pagingArgs.toArray());
responders.respond(routeContext, pagingStrategy.process(result, routeContext));
}
private List<Object> merge(final PaginationInfo paginationInfo, final Map<String, Object> arguments) {
final List<Object> methodArguments = new LinkedList<Object>();
arguments.remove(paginationInfo.getOffsetParamName());
arguments.remove(paginationInfo.getLimitParamName());
methodArguments.add(paginationInfo);
methodArguments.addAll(arguments.values());
return methodArguments;
}
public PagingStrategy getPagingStrategy(final Route route, final Map<String, Object> args) {
final Paginated paginated = route.getTargetMethod().getAnnotation(Paginated.class);
final String customHeader = paginated.customHeadersPrefix();
return Pagination.offset(paginated.offsetParamName(), argAsString(args, paginated.offsetParamName()))
.limitParam(paginated.limitParamName(), argAsString(args, paginated.limitParamName()))
.customHeadersPrefix(customHeader)
.webLinking(paginated.webLinking())
.build();
}
private String argAsString(final Map<String, Object> args, final String argName) {
return (String) args.get(argName);
}
private boolean hasPaginatedAnnotation(final Method targetMethod) {
return targetMethod.getAnnotation(Paginated.class) != null;
}
private Object getController(Route route) {
return controllerFactory.createController(route.getTargetClass(), beanManager);
}
}