001    // Copyright 2008, 2010, 2011, 2012 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    // http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry5.internal.services;
016    
017    import org.apache.tapestry5.SymbolConstants;
018    import org.apache.tapestry5.ioc.annotations.Inject;
019    import org.apache.tapestry5.ioc.annotations.Symbol;
020    import org.apache.tapestry5.ioc.internal.util.InternalUtils;
021    import org.apache.tapestry5.services.BaseURLSource;
022    import org.apache.tapestry5.services.Request;
023    
024    public class BaseURLSourceImpl implements BaseURLSource
025    {
026        private final Request request;
027    
028        private String hostname;
029        private int hostPort;
030        private int secureHostPort;
031    
032        public BaseURLSourceImpl(Request request, @Inject @Symbol(SymbolConstants.HOSTNAME) String hostname,
033                                 @Symbol(SymbolConstants.HOSTPORT) int hostPort, @Symbol(SymbolConstants.HOSTPORT_SECURE) int secureHostPort)
034        {
035            this.request = request;
036            this.hostname = hostname;
037            this.hostPort = hostPort;
038            this.secureHostPort = secureHostPort;
039        }
040    
041        public String getBaseURL(boolean secure)
042        {
043            return String.format("%s://%s%s",
044                    secure ? "https" : "http",
045                    hostname(),
046                    portExtension(secure));
047        }
048    
049        private String portExtension(boolean secure)
050        {
051            int port = secure ? secureHostPort : hostPort;
052    
053            // The default for the ports is 0, which means to use Request.serverPort. That's mostly
054            // for development.
055            if (port <= 0)
056            {
057                port = request.getServerPort();
058            }
059    
060            int expectedPort = secure ? 443 : 80;
061    
062            if (port == expectedPort)
063            {
064                return "";
065            }
066    
067            return ":" + port;
068        }
069    
070        private String hostname()
071        {
072    
073            if (InternalUtils.isBlank(hostname))
074            {
075                return request.getServerName();
076            }
077    
078            // This is common in some PaaS deployments, such as Heroku, where the port is passed in as
079            // and environment variable.
080    
081            if (this.hostname.startsWith("$"))
082            {
083                return System.getenv(hostname.substring(1));
084            }
085    
086            return hostname;
087        }
088    }