/*
* Copyright (c) 2005-2010, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
*
* WSO2 Inc. licenses this file to you 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.apache.synapse.rest;
import org.apache.axis2.Constants;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.synapse.MessageContext;
import org.apache.synapse.aspects.ComponentType;
import org.apache.synapse.aspects.flow.statistics.collectors.CloseEventCollector;
import org.apache.synapse.aspects.flow.statistics.collectors.OpenEventCollector;
import org.apache.synapse.aspects.flow.statistics.collectors.RuntimeStatisticCollector;
import org.apache.synapse.core.axis2.Axis2MessageContext;
import org.apache.synapse.rest.version.DefaultStrategy;
import java.util.*;
/**
* This class is responsible for receiving requests from various sources and dispatching
* them to a suitable REST API for further processing. This is the main entry point for
* mediating messages through APIs and Resources.
*/
public class RESTRequestHandler {
private static final Log log = LogFactory.getLog(RESTRequestHandler.class);
/**
* Attempt to process the given message through one of the available APIs. This method
* will first try to locate a suitable API for the given message by running it through
* the API validation routines available. If a matching API is found it will dispatch
* the message to the located API. If a matching API cannot be found, message will be
* left intact so any other handlers (eg: main sequence) can pick it up later.
*
* @param synCtx MessageContext of the request to be processed
* @return true if the message was dispatched to an API and false otherwise
*/
public boolean process(MessageContext synCtx) {
if (synCtx.isResponse()) {
return dispatchToAPI(synCtx);
}
org.apache.axis2.context.MessageContext msgCtx = ((Axis2MessageContext) synCtx).
getAxis2MessageContext();
String protocol = msgCtx.getIncomingTransportName();
if (!Constants.TRANSPORT_HTTP.equals(protocol) && !Constants.TRANSPORT_HTTPS.equals(protocol)) {
if (log.isDebugEnabled()) {
log.debug("Invalid protocol for REST API mediation: " + protocol);
}
return false;
}
return dispatchToAPI(synCtx);
}
private boolean dispatchToAPI(MessageContext synCtx) {
Collection<API> apiSet = synCtx.getEnvironment().getSynapseConfiguration().getAPIs();
//Since swapping elements are not possible with sets, Collection is converted to a List
List<API> defaultStrategyApiSet = new ArrayList<API>(apiSet);
API defaultAPI = null;
for (API api : apiSet) {
api.setLogSetterValue();
if ("/".equals(api.getContext())) {
defaultAPI = api;
} else if (api.getVersionStrategy().getClass().getName().equals(DefaultStrategy.class.getName())) {
//APIs whose VersionStrategy is bound to an instance of DefaultStrategy, should be skipped and processed at last.
//Otherwise they will be always chosen to process the request without matching the version.
defaultStrategyApiSet.add(api);
} else if (api.canProcess(synCtx)) {
if (log.isDebugEnabled()) {
log.debug("Located specific API: " + api.getName() + " for processing message");
}
api.process(synCtx);
return true;
}
}
for (API api : defaultStrategyApiSet) {
api.setLogSetterValue();
if (api.canProcess(synCtx)) {
if (log.isDebugEnabled()) {
log.debug("Located specific API: " + api.getName() + " for processing message");
}
apiProcess(synCtx, api);
return true;
}
}
if (defaultAPI != null && defaultAPI.canProcess(synCtx)) {
defaultAPI.setLogSetterValue();
apiProcess(synCtx, defaultAPI);
return true;
}
return false;
}
private void apiProcess(MessageContext synCtx, API api) {
Integer statisticReportingIndex = 0;
if (RuntimeStatisticCollector.isStatisticsEnabled()) {
statisticReportingIndex = OpenEventCollector
.reportEntryEvent(synCtx, api.getAPIName(), api.getAspectConfiguration(), ComponentType.API);
api.process(synCtx);
CloseEventCollector.tryEndFlow(synCtx, api.getAPIName(), ComponentType.API, statisticReportingIndex, true);
} else {
api.process(synCtx);
}
}
}