/*
* Copyright 2005 Joe Walker
*
* 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.directwebremoting.dwrp;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.directwebremoting.ConversionException;
import org.directwebremoting.ScriptBuffer;
import org.directwebremoting.WebContextFactory;
import org.directwebremoting.extend.Call;
import org.directwebremoting.extend.Calls;
import org.directwebremoting.extend.ConverterManager;
import org.directwebremoting.extend.EnginePrivate;
import org.directwebremoting.extend.FormField;
import org.directwebremoting.extend.InboundContext;
import org.directwebremoting.extend.InboundVariable;
import org.directwebremoting.extend.MethodDeclaration;
import org.directwebremoting.extend.ModuleManager;
import org.directwebremoting.extend.PageNormalizer;
import org.directwebremoting.extend.ParameterProperty;
import org.directwebremoting.extend.Property;
import org.directwebremoting.extend.ProtocolConstants;
import org.directwebremoting.extend.RealScriptSession;
import org.directwebremoting.extend.RealWebContext;
import org.directwebremoting.extend.Remoter;
import org.directwebremoting.extend.Replies;
import org.directwebremoting.extend.Reply;
import org.directwebremoting.extend.ScriptBufferUtil;
import org.directwebremoting.extend.ScriptConduit;
import org.directwebremoting.extend.SimpleInputStreamFactory;
import org.directwebremoting.impl.AccessLogLevel;
import org.directwebremoting.impl.ExportUtil;
import org.directwebremoting.io.FileTransfer;
import org.directwebremoting.io.InputStreamFactory;
import org.directwebremoting.util.DebuggingPrintWriter;
import org.directwebremoting.util.LocalUtil;
/**
* A Marshaller that output plain Javascript.
* This marshaller can be tweaked to output Javascript in an HTML context.
* This class works in concert with CallScriptConduit, they should be
* considered closely related and it is important to understand what one does
* while editing the other.
* @author Joe Walker [joe at getahead dot ltd dot uk]
*/
public abstract class BaseCallHandler extends BaseDwrpHandler
{
/* (non-Javadoc)
* @see org.directwebremoting.Handler#handle(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
public void handle(HttpServletRequest request, HttpServletResponse response) throws IOException
{
try
{
CallBatch batch = new CallBatch(request);
// Security checks first, once we've parsed the input
checkGetAllowed(batch);
boolean checkCsrf = false;
for (int i = 0; i < batch.getCalls().getCallCount(); i++)
{
Call call = batch.getCalls().getCall(i);
if (!ExportUtil.isUnprotectedSystemMethod(call.getScriptName(), call.getMethodName()))
{
checkCsrf = true;
break;
}
}
if (checkCsrf) {
checkNotCsrfAttack(request, batch);
}
// Save the batch so marshallException can get at a batch id
request.setAttribute(ATTRIBUTE_BATCH, batch);
String normalizedPage = pageNormalizer.normalizePage(batch.getPage());
RealWebContext webContext = (RealWebContext) WebContextFactory.get();
webContext.checkPageInformation(normalizedPage, batch.getScriptSessionId(), batch.getWindowName());
// Various bits of the CallBatch need to be stashed away places
storeParsedRequest(request, webContext, batch);
Calls calls = marshallInbound(batch);
Replies replies = remoter.execute(calls);
marshallOutbound(replies, response);
}
catch (Exception ex)
{
marshallException(request, response, ex);
}
}
/**
* Convert batch into calls.
* @param batch The data we've parsed from the request
* @return The function calls to make
*/
@SuppressWarnings({"ThrowableInstanceNeverThrown"})
public Calls marshallInbound(CallBatch batch)
{
Calls calls = batch.getCalls();
// Debug the environment
/*
if (log.isDebugEnabled() && calls.getCallCount() > 0)
{
// We can just use 0 because they are all shared
InboundContext inctx = batch.getInboundContexts().get(0);
StringBuffer buffer = new StringBuffer();
for (Iterator<String> it = inctx.getInboundVariableNames(); it.hasNext();)
{
String key = it.next();
InboundVariable value = inctx.getInboundVariable(key);
if (key.startsWith(ProtocolConstants.INBOUND_CALLNUM_PREFIX) &&
key.contains(ProtocolConstants.INBOUND_CALLNUM_SUFFIX + ProtocolConstants.INBOUND_KEY_ENV))
{
buffer.append(key);
buffer.append('=');
buffer.append(value.toString());
buffer.append(", ");
}
}
if (buffer.length() > 0)
{
log.debug("Environment: " + buffer.toString());
}
}
//*/
callLoop:
for (int callNum = 0; callNum < calls.getCallCount(); callNum++)
{
Call call = calls.getCall(callNum);
try
{
InboundContext inctx = batch.getInboundContexts().get(callNum);
// Get a list of the available matching methods with the coerced
// parameters that we will use to call it if we choose to use
// that method.
// Which method are we using?
call.findMethod(moduleManager, converterManager, inctx, callNum);
MethodDeclaration method = call.getMethodDeclaration();
if (method == null)
{
log.warn("No methods to match " + call.getScriptName() + '.' + call.getMethodName());
throw new IllegalArgumentException("Missing method or missing parameter converters");
}
// We are now sure we have the set of inputs lined up. They may
// cross-reference so we do the de-referencing all in one go.
// TODO: should we do this here? - why not earlier?
// do we need to know the method before we dereference?
inctx.dereference();
// Convert all the parameters to the correct types
int destParamCount = method.getParameterTypes().length;
Object[] arguments = new Object[destParamCount];
int inboundArgIndex = 0;
for (int outboundArgIndex = 0; outboundArgIndex < destParamCount; outboundArgIndex++)
{
InboundVariable param;
if (method.isVarArgs() && outboundArgIndex + 1 == destParamCount)
{
param = inctx.createArrayWrapper(callNum, destParamCount);
}
else
{
param = inctx.getParameter(callNum, inboundArgIndex);
}
Property property = new ParameterProperty(method, outboundArgIndex);
// TODO: Having just got a property, shouldn't we call property.getPropertyType() in place of this?
Class<?> paramType = method.getParameterTypes()[outboundArgIndex];
try
{
arguments[outboundArgIndex] = converterManager.convertInbound(paramType, param, property);
}
catch (Exception ex)
{
log.debug("Problem converting param=" + param + ", property=" + property + ", into paramType=" + paramType.getName() + ": " + ex);
throw ex;
}
// Only increment the inboundArgIndex if the parameterType of the destination method is not
// a Servlet class. // In this case the arguments value is auto-populated by DWR and a place-holder
// argument is not passed from the client.
if (!LocalUtil.isServletClass(paramType)) {
inboundArgIndex++;
}
}
call.setParameters(arguments);
}
catch (Exception ex)
{
log.debug("Marshalling exception", ex);
call.setMarshallFailure(ex);
continue callLoop;
}
}
return calls;
}
/**
* Build a CallBatch and put it in the request
* @param request Where we store the parsed data
* @param webContext We need to notify others of some of the data we find
* @param batch The parsed data to store
*/
private void storeParsedRequest(HttpServletRequest request, RealWebContext webContext, CallBatch batch) throws IOException
{
// Remaining parameters get put into the request for later consumption
Map<String, FormField> paramMap = batch.getExtraParameters();
if (!paramMap.isEmpty())
{
for (Map.Entry<String, FormField> entry : paramMap.entrySet())
{
String key = entry.getKey();
final FormField formField = entry.getValue();
Object value;
if (formField == null)
{
log.warn("Found a parameter with a null value. This is likely to be due to a URL with an & before the query parameters. Please URL encode such pages.");
throw new IllegalArgumentException("Empty input parameter. See logs for suggestions");
}
if (formField.isFile())
{
InputStreamFactory inFactory = new SimpleInputStreamFactory(formField.getInputStream());
value = new FileTransfer(formField.getName(), formField.getMimeType(), formField.getFileSize(), inFactory);
}
else
{
value = formField.getString();
}
if (key.startsWith(ProtocolConstants.INBOUND_KEY_METADATA))
{
request.setAttribute(key.substring(ProtocolConstants.INBOUND_KEY_METADATA.length()), value);
log.debug("Moved param to request: " + key + "=" + value);
}
else
{
log.debug("Ignoring parameter: " + key + "=" + value);
}
}
}
}
/* (non-Javadoc)
* @see org.directwebremoting.Marshaller#marshallOutbound(org.directwebremoting.Replies, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
public void marshallOutbound(Replies replies, HttpServletResponse response) throws IOException
{
RealScriptSession scriptSession;
try
{
scriptSession = (RealScriptSession) WebContextFactory.get().getScriptSession();
}
catch (SecurityException ex)
{
// If this is a call to System.pageUnloaded() or if something else
// has caused the ScriptSession to expire, then we shouldn't do any
// output, and just ignore the write. Officially there isn't
// anything to write to anyway.
return;
}
// Basic setup
response.setContentType(getOutboundMimeType());
PrintWriter out;
// AccessLogLevel.getValue is null safe, it will always return an AccessLogLevel.
if (debugScriptOutput || AccessLogLevel.getValue(this.accessLogLevel, debug).hierarchy() == 0)
{
// This might be considered evil - altering the program flow
// depending on the log status, however DebuggingPrintWriter is
// very thin and only about logging
out = new DebuggingPrintWriter("", response.getWriter());
}
else
{
out = response.getWriter();
}
// The conduit to pass on reverse ajax scripts
ScriptConduit conduit = new CallScriptConduit(out);
// Setup a debugging prefix
if (out instanceof DebuggingPrintWriter)
{
DebuggingPrintWriter dpw = (DebuggingPrintWriter) out;
dpw.setPrefix("out(" + conduit.hashCode() + "): ");
}
// Send the script prefix (if any)
sendOutboundScriptPrefix(out, replies.getCalls().getInstanceId(), replies.getCalls().getBatchId());
out.println(ProtocolConstants.SCRIPT_CALL_INSERT);
scriptSession.writeScripts(conduit);
out.println(ProtocolConstants.SCRIPT_CALL_REPLY);
String batchId = replies.getCalls().getBatchId();
for (int i = 0; i < replies.getReplyCount(); i++)
{
Reply reply = replies.getReply(i);
String callId = reply.getCallId();
try
{
// The existence of a throwable indicates that something went wrong
if (reply.getThrowable() != null)
{
Throwable ex = reply.getThrowable();
ScriptBuffer script = EnginePrivate.getRemoteHandleExceptionScript(batchId, callId, ex);
conduit.addScript(script);
// TODO: Are there any reasons why we should be logging here (and in the ConversionException handler)
//log.warn("--Erroring: batchId[" + batchId + "] message[" + ex.toString() + ']'), ex;
}
else
{
Object data = reply.getReply();
ScriptBuffer script = EnginePrivate.getRemoteHandleCallbackScript(batchId, callId, data);
conduit.addScript(script);
}
}
catch (IOException ex)
{
// We're a bit stuck we died half way through writing so
// we can't be sure the browser can react to the failure.
// Since we can no longer do output we just log and end
log.error("--Output Error: batchId[" + batchId + "] message[" + ex.toString() + ']', ex);
}
catch (ConversionException ex)
{
ScriptBuffer script = EnginePrivate.getRemoteHandleExceptionScript(batchId, callId, ex);
addScriptHandleExceptions(conduit, script);
log.warn("--ConversionException: batchId=" + batchId + " class=" + ex.getConversionType().getName(), ex);
}
catch (Exception ex)
{
// This is a bit of a "this can't happen" case so I am a bit
// nervous about sending the exception to the client, but we
// want to avoid silently dying so we need to do something.
ScriptBuffer script = EnginePrivate.getRemoteHandleExceptionScript(batchId, callId, ex);
addScriptHandleExceptions(conduit, script);
log.error("--ConversionException: batchId=" + batchId + " message=" + ex.toString());
}
}
sendOutboundScriptSuffix(out, replies.getCalls().getInstanceId(), replies.getCalls().getBatchId());
}
/* (non-Javadoc)
* @see org.directwebremoting.extend.Marshaller#marshallException(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, java.lang.Exception)
*/
public void marshallException(HttpServletRequest request, HttpServletResponse response, Exception ex) throws IOException
{
response.setContentType(getOutboundMimeType());
PrintWriter out = response.getWriter();
CallBatch batch = (CallBatch) request.getAttribute(ATTRIBUTE_BATCH);
String batchId = null;
String instanceId = "0";
if (batch != null && batch.getCalls() != null)
{
batchId = batch.getCalls().getBatchId();
instanceId = batch.getCalls().getInstanceId();
}
if (debug)
{
log.warn("Exception while processing batch", ex);
}
sendOutboundScriptPrefix(out, instanceId, batchId);
String script = EnginePrivate.getRemoteHandleBatchExceptionScript(batchId, ex);
out.print(script);
sendOutboundScriptSuffix(out, instanceId, batchId);
}
/**
* Marshall a Script without worrying about MarshallExceptions
*/
public void addScriptHandleExceptions(ScriptConduit conduit, ScriptBuffer script) throws IOException
{
try
{
conduit.addScript(script);
}
catch (ConversionException ex)
{
log.warn("Error marshalling exception. Is the exception converter configured?", ex);
}
}
/**
* Send a script to the browser
* @param out The stream to write to
* @param script The script to send
* @throws IOException If the write fails
*/
protected abstract void sendScript(PrintWriter out, String script) throws IOException;
/**
* What mime type should we send to the browser for this data?
* @return A mime-type
*/
protected abstract String getOutboundMimeType();
/**
* iframe mode starts as HTML, so get into script mode
* @param out The stream to write to
* @param batchId The batch identifier so we can prepare the environment
* @throws IOException If the write fails
*/
protected abstract void sendOutboundScriptPrefix(PrintWriter out, String instanceId, String batchId) throws IOException;
/**
* iframe mode needs to get out of script mode
* @param out The stream to write to
* @param batchId The batch identifier so we can prepare the environment
* @throws IOException If the write fails
*/
protected abstract void sendOutboundScriptSuffix(PrintWriter out, String instanceId, String batchId) throws IOException;
/* (non-Javadoc)
* @see org.directwebremoting.Marshaller#isConvertable(java.lang.Class)
*/
public boolean isConvertable(Class<?> paramType)
{
return converterManager.isConvertable(paramType);
}
/**
* A ScriptConduit that works with the parent Marshaller.
* In some ways this is nasty because it has access to essentially private parts
* of BaseCallHandler, however there is nowhere sensible to store them
* within that class, so this is a hacky simplification.
* @author Joe Walker [joe at getahead dot ltd dot uk]
*/
protected class CallScriptConduit extends ScriptConduit
{
/**
* Simple ctor
* @param out The stream to write to
*/
protected CallScriptConduit(PrintWriter out)
{
super(RANK_FAST, false);
if (out == null)
{
throw new NullPointerException("out=null");
}
this.out = out;
}
/* (non-Javadoc)
* @see org.directwebremoting.ScriptConduit#addScript(org.directwebremoting.ScriptBuffer)
*/
@Override
public boolean addScript(ScriptBuffer script) throws IOException, ConversionException
{
sendScript(out, ScriptBufferUtil.createOutput(script, converterManager, jsonOutput));
return true;
}
/**
* The PrintWriter to send output to, and that we should synchronize against
*/
private final PrintWriter out;
}
/**
* Set the debug status
* @param debug The new debug setting
*/
public void setDebug(boolean debug)
{
this.debug = debug;
}
/**
* Are we in debug mode?
*/
protected boolean debug = false;
/**
* Setter for the remoter
* @param remoter The new remoter
*/
public void setRemoter(Remoter remoter)
{
this.remoter = remoter;
}
/**
* The bean to execute remote requests and generate interfaces
*/
protected Remoter remoter = null;
/**
* Do we debug all the scripts that we output?
* @param debugScriptOutput true to debug all of the output scripts (verbose)
*/
public void setDebugScriptOutput(boolean debugScriptOutput)
{
this.debugScriptOutput = debugScriptOutput;
}
/**
* Do we debug all the scripts that we output?
*/
protected boolean debugScriptOutput = false;
/**
* @return Are we outputting in JSON mode?
*/
public boolean isJsonOutput()
{
return jsonOutput;
}
/**
* @param jsonOutput Are we outputting in JSON mode?
*/
public void setJsonOutput(boolean jsonOutput)
{
this.jsonOutput = jsonOutput;
}
/**
* Are we outputting in JSON mode?
*/
protected boolean jsonOutput = false;
/**
* When and what should we log? Options are (specified in the DWR servlet's init-params):
* 1) call (start of call + successful return values).
* 2) exception (checked) - default for debug.
* 3) runtimeexception (unchecked).
* 4) error - default for production.
* 5) off.
*/
public void setAccessLogLevel(String accessLogLevel)
{
this.accessLogLevel = accessLogLevel;
}
/**
* When and what should we log? Options are (specified in the DWR servlet's init-params):
* 1) call (start of call + successful return values).
* 2) exception (checked) - default for debug.
* 3) runtimeexception (unchecked).
* 4) error - default for production.
* 5) off.
*/
protected String accessLogLevel = null;
/**
* Accessor for the PageNormalizer.
* @param pageNormalizer The new PageNormalizer
*/
public void setPageNormalizer(PageNormalizer pageNormalizer)
{
this.pageNormalizer = pageNormalizer;
}
/**
* How we turn pages into the canonical form.
*/
protected PageNormalizer pageNormalizer = null;
/**
* Accessor for the ConverterManager that we configure
* @param converterManager
*/
public void setConverterManager(ConverterManager converterManager)
{
this.converterManager = converterManager;
}
/**
* How we convert parameters
*/
protected ConverterManager converterManager = null;
/**
* Accessor for the ModuleManager that we configure
* @param moduleManager
*/
public void setModuleManager(ModuleManager moduleManager)
{
this.moduleManager = moduleManager;
}
/**
* How we create new beans
*/
protected ModuleManager moduleManager = null;
/**
* How we stash away the results of the request parse
*/
protected static final String ATTRIBUTE_BATCH = "org.directwebremoting.dwrp.batch";
/**
* The log stream
*/
private static final Log log = LogFactory.getLog(BaseCallHandler.class);
}