/*
* 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.felix.webconsole.plugins.event.internal;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.lang.reflect.Array;
import java.net.URL;
import java.util.*;
import java.util.Map.Entry;
import javax.servlet.ServletException;
import javax.servlet.http.*;
import org.osgi.service.event.Event;
import org.osgi.service.event.EventAdmin;
/**
* The Event Plugin
*/
public class PluginServlet extends HttpServlet
{
private static final String ACTION_POST = "post"; //$NON-NLS-1$
private static final String ACTION_SEND = "send"; //$NON-NLS-1$
private static final String ACTION_CLEAR = "clear"; //$NON-NLS-1$
private static final String PARAMETER_ACTION = "action"; //$NON-NLS-1$
/** The event collector. */
private final EventCollector collector;
/** Is the config admin available? */
private volatile boolean configAdminAvailable = false;
private EventAdmin eventAdmin;
private final String TEMPLATE;
public PluginServlet()
{
this.collector = new EventCollector(null);
TEMPLATE = readTemplateFile(getClass(), "/res/events.html"); //$NON-NLS-1$
}
private final String readTemplateFile(final Class clazz, final String templateFile)
{
InputStream templateStream = getClass().getResourceAsStream(templateFile);
if (templateStream != null)
{
ByteArrayOutputStream baos = new ByteArrayOutputStream();
byte[] data = new byte[1024];
try
{
int len = 0;
while ((len = templateStream.read(data)) > 0)
{
baos.write(data, 0, len);
}
return baos.toString("UTF-8"); //$NON-NLS-1$
}
catch (IOException e)
{
// don't use new Exception(message, cause) because cause is 1.4+
throw new RuntimeException("readTemplateFile: Error loading "
+ templateFile + ": " + e);
}
finally
{
try
{
templateStream.close();
}
catch (IOException e)
{
/* ignore */
}
}
}
// template file does not exist, return an empty string
log("readTemplateFile: File '" + templateFile + "' not found through class "
+ clazz);
return ""; //$NON-NLS-1$
}
private static final Event newEvent(HttpServletRequest request)
{
String topic = request.getParameter("topic"); //$NON-NLS-1$
return new Event(topic, (Dictionary)PropertiesEditorSupport.convertProperties(request));
}
/**
* @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
*/
protected void doPost( HttpServletRequest req, HttpServletResponse resp )
throws ServletException, IOException
{
final String action = req.getParameter( PARAMETER_ACTION );
if ( ACTION_POST.equals(action) ) {
final Event event = newEvent(req);
eventAdmin.postEvent(event);
} else if (ACTION_SEND.equals(action)) {
final Event event = newEvent(req);
eventAdmin.sendEvent(event);
} else if ( ACTION_CLEAR.equals( action ) ) {
this.collector.clear();
}
// we always send back the json data
resp.setContentType( "application/json" ); //$NON-NLS-1$
resp.setCharacterEncoding( "utf-8" ); //$NON-NLS-1$
renderJSON( resp.getWriter() );
}
private void renderJSON( final PrintWriter pw ) throws IOException
{
List events = this.collector.getEvents();
StringBuffer statusLine = new StringBuffer();
statusLine.append( events.size() );
statusLine.append( " Event");
if ( events.size() != 1 )
{
statusLine.append('s');
}
statusLine.append( " received" );
if ( !events.isEmpty() )
{
statusLine.append( " since " );
Date d = new Date();
d.setTime( ( ( EventInfo ) events.get( 0 ) ).received );
statusLine.append( d );
}
statusLine.append( ". (Event admin: " );
if ( this.eventAdmin == null )
{
statusLine.append("un");
}
statusLine.append("available; Config admin: ");
if ( !this.configAdminAvailable )
{
statusLine.append("un");
}
statusLine.append("available)");
// Compute scale: startTime is 0, lastTimestamp is 100%
final long startTime = this.collector.getStartTime();
final long endTime = (events.size() == 0 ? startTime : ((EventInfo)events.get(events.size() - 1)).received);
final float scale = (endTime == startTime ? 100.0f : 100.0f / (endTime - startTime));
pw.write("{");
jsonKey( pw, "status" );
jsonValue( pw, statusLine.toString() );
pw.write(',');
jsonKey( pw, "data" );
pw.write('[');
// display list in reverse order
for ( int index = events.size() - 1; index >= 0; index-- )
{
eventJson( pw, ( EventInfo ) events.get( index ), index, startTime, scale );
if ( index > 0 )
{
pw.write(',');
}
}
pw.write(']');
pw.write("}"); //$NON-NLS-1$
}
protected void doGet( HttpServletRequest request, HttpServletResponse response )
throws ServletException, IOException
{
final String info = request.getPathInfo();
if ( info.endsWith( ".json" ) ) //$NON-NLS-1$
{
response.setContentType( "application/json" ); //$NON-NLS-1$
response.setCharacterEncoding( "UTF-8" ); //$NON-NLS-1$
PrintWriter pw = response.getWriter();
this.renderJSON( pw );
// nothing more to do
return;
}
this.renderContent( request, response );
}
protected void renderContent( HttpServletRequest request, HttpServletResponse response )
throws ServletException, IOException
{
final PrintWriter pw = response.getWriter();
//final String appRoot = ( String ) request.getAttribute( "felix.webconsole.appRoot" );
//pw.println( "<script src='" + appRoot + "/events/res/ui/" + "events.js" + "' type='text/javascript'></script>" );
pw.print(TEMPLATE);
}
public URL getResource(String path)
{
if ( path.startsWith("/events/res/ui/") ) //$NON-NLS-1$
{
return this.getClass().getResource(path.substring(7));
}
return null;
}
private void jsonValue( final PrintWriter pw, final String v)
throws IOException
{
if (v == null || v.length() == 0)
{
pw.write("\"\"");
return;
}
pw.write('"');
char previousChar = 0;
char c;
for (int i = 0; i < v.length(); i += 1)
{
c = v.charAt(i);
switch (c)
{
case '\\':
case '"':
pw.write('\\');
pw.write(c);
break;
case '/':
if (previousChar == '<')
{
pw.write('\\');
}
pw.write(c);
break;
case '\b':
pw.write("\\b");
break;
case '\t':
pw.write("\\t");
break;
case '\n':
pw.write("\\n");
break;
case '\f':
pw.write("\\f");
break;
case '\r':
pw.write("\\r");
break;
default:
if (c < ' ')
{
final String hexValue = "000" + Integer.toHexString(c);
pw.write("\\u");
pw.write(hexValue.substring(hexValue.length() - 4));
}
else
{
pw.write(c);
}
}
previousChar = c;
}
pw.write('"');
}
private void jsonValue( final PrintWriter pw, final long l)
{
pw.write(Long.toString(l));
}
private void jsonKey( final PrintWriter pw, String key)
throws IOException
{
jsonValue( pw, key);
pw.write(':');
}
private void eventJson( PrintWriter jw, EventInfo info, int index, final long start, final float scale )
throws IOException
{
final long msec = info.received - start;
// Compute color bar size and make sure the bar is visible
final int percent = Math.max((int)(msec * scale), 2);
jw.write("{");
jsonKey(jw, "id" );
jsonValue(jw, String.valueOf( index ) );
jw.write(',');
jsonKey(jw, "offset" );
jsonValue(jw, msec );
jw.write(',');
jsonKey(jw, "width" );
jsonValue(jw, percent );
jw.write(',');
jsonKey(jw, "category" );
jsonValue(jw, info.category );
jw.write(',');
jsonKey(jw, "received" );
jsonValue(jw, info.received );
jw.write(',');
jsonKey(jw, "topic" );
jsonValue(jw, info.topic );
if ( info.info != null )
{
jw.write(',');
jsonKey(jw, "info" );
jsonValue(jw, info.info );
}
jw.write(',');
jsonKey(jw, "properties" );
jw.write("{");
if ( info.properties != null && info.properties.size() > 0 )
{
final Iterator i = info.properties.entrySet().iterator();
boolean first = true;
while ( i.hasNext() )
{
final Map.Entry current = (Entry) i.next();
if ( !first)
{
jw.write(',');
}
first = false;
jsonKey(jw, current.getKey().toString() );
final Object value = current.getValue();
if ( null == value )
{
jw.write("null"); //$NON-NLS-1$
}
else if ( value.getClass().isArray() )
{
// as we can't use 1.5 functionality we have to print the array ourselves
final StringBuffer b = new StringBuffer("[");
final int arrayLength = Array.getLength(value);
for(int m=0; m<arrayLength; m++) {
if ( m > 0 )
{
b.append(", ");
}
b.append( Array.get(value, m).toString() );
}
b.append(']');
jsonValue(jw, b.toString());
}
else
{
jsonValue(jw, value.toString());
}
}
}
jw.write("}");
jw.write("}");
}
public void updateConfiguration( Dictionary dict)
{
this.collector.updateConfiguration(dict);
}
public EventCollector getCollector()
{
return this.collector;
}
public void setEventAdmin(final EventAdmin eventAdmin)
{
this.eventAdmin = eventAdmin;
}
public void setConfigAdminAvailable(final boolean flag)
{
this.configAdminAvailable = flag;
}
}