/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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.tuscany.sca.binding.jsonrpc.provider;
import java.io.BufferedReader;
import java.io.CharArrayWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.InvocationTargetException;
import java.util.List;
import javax.servlet.ServletConfig;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.tuscany.sca.assembly.Binding;
import org.apache.tuscany.sca.interfacedef.InterfaceContract;
import org.apache.tuscany.sca.interfacedef.Operation;
import org.apache.tuscany.sca.runtime.RuntimeComponentService;
import org.apache.tuscany.sca.runtime.RuntimeWire;
import org.json.JSONArray;
import org.json.JSONObject;
import org.osoa.sca.ServiceRuntimeException;
import com.metaparadigm.jsonrpc.JSONRPCBridge;
import com.metaparadigm.jsonrpc.JSONRPCResult;
import com.metaparadigm.jsonrpc.JSONRPCServlet;
/**
* Servlet that handles JSON-RPC requests invoking SCA services.
*
* There is an instance of this Servlet for each <binding.jsonrpc>
*
* @version $Rev: 677479 $ $Date: 2008-07-17 01:36:25 +0100 (Thu, 17 Jul 2008) $
*/
public class JSONRPCServiceServlet extends JSONRPCServlet {
private static final long serialVersionUID = 1L;
transient Binding binding;
transient String serviceName;
transient Object serviceInstance;
transient RuntimeComponentService componentService;
transient InterfaceContract serviceContract;
transient Class<?> serviceInterface;
public JSONRPCServiceServlet(Binding binding,
RuntimeComponentService componentService,
InterfaceContract serviceContract,
Class<?> serviceInterface,
Object serviceInstance) {
this.binding = binding;
this.serviceName = binding.getName();
this.componentService = componentService;
this.serviceContract = serviceContract;
this.serviceInterface = serviceInterface;
this.serviceInstance = serviceInstance;
}
/**
* Override to do nothing as the JSONRPCServlet is setup by the
* service method in this class.
*/
@Override
public void init(ServletConfig config) {
}
@Override
public void service(HttpServletRequest request, HttpServletResponse response) throws IOException {
if ("smd".equals(request.getQueryString())) {
handleSMDRequest(request, response);
} else {
try {
handleServiceRequest(request, response);
} finally {
HttpSession session = request.getSession(false);
if (session != null) {
session.removeAttribute("JSONRPCBridge");
}
}
}
}
private void handleServiceRequest(HttpServletRequest request, HttpServletResponse response)
throws IOException {
// Encode using UTF-8, although We are actually ASCII clean as
// all unicode data is JSON escaped using backslash u. This is
// less data efficient for foreign character sets but it is
// needed to support naughty browsers such as Konqueror and Safari
// which do not honour the charset set in the response
response.setContentType("text/plain;charset=utf-8");
OutputStream out = response.getOutputStream();
// Decode using the charset in the request if it exists otherwise
// use UTF-8 as this is what all browser implementations use.
// The JSON-RPC-Java JavaScript client is ASCII clean so it
// although here we can correctly handle data from other clients
// that do not escape non ASCII data
String charset = request.getCharacterEncoding();
if (charset == null) {
charset = "UTF-8";
}
BufferedReader in = new BufferedReader(new InputStreamReader(request.getInputStream(), charset));
// Read the request
CharArrayWriter data = new CharArrayWriter();
char[] buf = new char[4096];
int ret;
while ((ret = in.read(buf, 0, 4096)) != -1) {
data.write(buf, 0, ret);
}
JSONObject jsonReq = null;
String method = null;
try {
jsonReq = new JSONObject(data.toString());
method = jsonReq.getString("method");
} catch (Exception e) {
//FIXME Exceptions are not handled correctly here
// They should be reported to the client JavaScript as proper
// JavaScript exceptions.
throw new RuntimeException("Unable to parse request", e);
}
// check if it's a system request
// or a method invocation
byte[] bout;
if (method.startsWith("system.")) {
bout = handleJSONRPCSystemInvocation(request, response, data.toString());
} else {
bout = handleJSONRPCMethodInvocation(request, response, jsonReq);
}
// Send response to client
out.write(bout);
out.flush();
out.close();
}
/**
* handles requests for the SMD descriptor for a service
*/
protected void handleSMDRequest(HttpServletRequest request, HttpServletResponse response) throws IOException,
UnsupportedEncodingException {
String serviceUrl = request.getRequestURL().toString();
String smd = JavaToSmd.interfaceToSmd(serviceInterface, serviceUrl);
response.setContentType("text/plain;charset=utf-8");
OutputStream out = response.getOutputStream();
byte[] bout = smd.getBytes("UTF-8");
out.write(bout);
out.flush();
out.close();
}
protected byte[] handleJSONRPCSystemInvocation(HttpServletRequest request, HttpServletResponse response, String requestData) throws IOException,
UnsupportedEncodingException {
/*
* Create a new bridge for every request to avoid all the problems with
* JSON-RPC-Java storing the bridge in the session
*/
HttpSession session = request.getSession();
JSONRPCBridge jsonrpcBridge = new JSONRPCBridge();
jsonrpcBridge.registerObject("Service", serviceInstance, serviceInterface);
session.setAttribute("JSONRPCBridge", jsonrpcBridge);
org.json.JSONObject jsonReq = null;
com.metaparadigm.jsonrpc.JSONRPCResult jsonResp = null;
try {
jsonReq = new org.json.JSONObject(requestData);
} catch (java.text.ParseException e) {
throw new RuntimeException("Unable to parse request", e);
}
String method = jsonReq.getString("method");
if ((method != null) && (method.indexOf('.') < 0)) {
jsonReq.putOpt("method", "Service" + "." + method);
}
// invoke the request
jsonResp = jsonrpcBridge.call(new Object[] {request}, jsonReq);
return jsonResp.toString().getBytes("UTF-8");
}
protected byte[] handleJSONRPCMethodInvocation(HttpServletRequest request, HttpServletResponse response, JSONObject jsonReq) throws IOException,
UnsupportedEncodingException {
String method = null;
Object[] args = null;
Object id = null;
try {
// Extract the method
method = jsonReq.getString("method");
if ((method != null) && (method.indexOf('.') < 0)) {
jsonReq.putOpt("method", "Service" + "." + method);
}
// Extract the arguments
JSONArray array = jsonReq.getJSONArray("params");
args = new Object[array.length()];
for (int i = 0; i < args.length; i++) {
args[i] = array.get(i);
}
id = jsonReq.get("id");
} catch (Exception e) {
throw new RuntimeException("Unable to find json method name", e);
}
// invoke the request
RuntimeWire wire = componentService.getRuntimeWire(binding, serviceContract);
Operation jsonOperation = findOperation(method);
Object result = null;
try {
JSONObject jsonResponse = new JSONObject();
result = wire.invoke(jsonOperation, args);
try {
jsonResponse.put("result", result);
jsonResponse.putOpt("id", id);
//get response to send to client
return jsonResponse.toString().getBytes("UTF-8");
} catch (Exception e) {
throw new ServiceRuntimeException("Unable to create JSON response", e);
}
} catch (InvocationTargetException e) {
JSONRPCResult errorResult = new JSONRPCResult(JSONRPCResult.CODE_REMOTE_EXCEPTION, id, e.getCause() );
return errorResult.toString().getBytes("UTF-8");
} catch(RuntimeException e) {
JSONRPCResult errorResult = new JSONRPCResult(JSONRPCResult.CODE_REMOTE_EXCEPTION, id, e.getCause());
return errorResult.toString().getBytes("UTF-8");
}
}
/**
* Find the operation from the component service contract
* @param componentService
* @param method
* @return
*/
private Operation findOperation(String method) {
if (method.contains(".")) {
method = method.substring(method.lastIndexOf(".") + 1);
}
List<Operation> operations = serviceContract.getInterface().getOperations();
//componentService.getBindingProvider(binding).getBindingInterfaceContract().getInterface().getOperations();
Operation result = null;
for (Operation o : operations) {
if (o.getName().equalsIgnoreCase(method)) {
result = o;
break;
}
}
return result;
}
}