# ClientWorker.java

    /**
     *  Copyright (c) 2009, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
     *
     *  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.apache.synapse.transport.passthru;

    import org.apache.axiom.om.OMAbstractFactory;
    import org.apache.axiom.soap.SOAPEnvelope;
    import org.apache.axiom.soap.SOAPFactory;
    import org.apache.axiom.soap.impl.llom.soap11.SOAP11Factory;
    import org.apache.axis2.AxisFault;
    import org.apache.axis2.Constants;
    import org.apache.axis2.addressing.AddressingConstants;
    import org.apache.axis2.builder.BuilderUtil;
    import org.apache.axis2.context.MessageContext;
    import org.apache.axis2.description.Parameter;
    import org.apache.axis2.description.WSDL2Constants;
    import org.apache.axis2.engine.AxisEngine;
    import org.apache.axis2.util.JavaUtils;
    import org.apache.axis2.wsdl.WSDLConstants;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.http.HttpStatus;
    import org.apache.http.nio.NHttpServerConnection;
    import org.apache.http.protocol.HTTP;
    import org.apache.synapse.commons.CorrelationConstants;
    import org.apache.synapse.commons.util.ext.TenantInfoInitiator;
    import org.apache.synapse.commons.util.ext.TenantInfoInitiatorProvider;
    import org.apache.synapse.transport.customlogsetter.CustomLogSetter;
    import org.apache.synapse.transport.http.conn.SynapseDebugInfoHolder;
    import org.apache.synapse.transport.nhttp.NhttpConstants;
    import org.apache.synapse.transport.passthru.config.PassThroughConfiguration;
    import org.apache.synapse.transport.passthru.config.TargetConfiguration;
    import org.apache.synapse.transport.passthru.util.RelayUtils;

    import java.net.MalformedURLException;
    import java.net.URL;
    import java.util.Collections;
    import java.util.Comparator;
    import java.util.List;
    import java.util.Map;
    import java.util.Set;
    import java.util.TreeMap;

    public class ClientWorker implements Runnable {
        private Log log = LogFactory.getLog(ClientWorker.class);
        /** the Http connectors configuration context */
        private TargetConfiguration targetConfiguration = null;
        /** the response message context that would be created */
        private org.apache.axis2.context.MessageContext responseMsgCtx = null;
        /** the HttpResponse received */
        private TargetResponse response = null;
        /** weather a body is expected or not */
        private boolean expectEntityBody = true;
        /** the axis2 message context of the request */
        private MessageContext requestMessageContext;

        private PassThroughConfiguration conf = PassThroughConfiguration.getInstance();

        public ClientWorker(TargetConfiguration targetConfiguration, MessageContext outMsgCtx, TargetResponse response) {
            this(targetConfiguration, outMsgCtx, response, Collections.emptyList());
        }

        public ClientWorker(TargetConfiguration targetConfiguration, MessageContext outMsgCtx, TargetResponse response,
                            List<String> allowedResponseProperties) {
            this.targetConfiguration = targetConfiguration;
            this.response = response;
            this.expectEntityBody = response.isExpectResponseBody();
            this.requestMessageContext = outMsgCtx;
            Map<String,String> headers = response.getHeaders();
            Map excessHeaders = response.getExcessHeaders();

    		String oriURL = headers.get(PassThroughConstants.LOCATION);
            if (outMsgCtx.getProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONNECTION) != null) {
                ((NHttpServerConnection) outMsgCtx.getProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONNECTION)).
                           getContext().setAttribute(PassThroughConstants.CLIENT_WORKER_INIT_TIME, System.currentTimeMillis());
            }
            // Special casing 301, 302, 303 and 307 scenario in following section. Not sure whether it's the correct fix,
    		// but this fix makes it possible to do http --> https redirection.
            if (oriURL != null && ((response.getStatus() != HttpStatus.SC_MOVED_TEMPORARILY) &&
                    (response.getStatus() != HttpStatus.SC_MOVED_PERMANENTLY) &&
                    (response.getStatus() != HttpStatus.SC_CREATED) &&
    		(response.getStatus() != HttpStatus.SC_SEE_OTHER) &&
    		(response.getStatus() != HttpStatus.SC_TEMPORARY_REDIRECT) &&
            !targetConfiguration.isPreserveHttpHeader(PassThroughConstants.LOCATION))) {
                URL url;
                String urlContext = null;
                try {
                    url = new URL(oriURL);
                    urlContext = url.getFile();
                } catch (MalformedURLException e) {
                    //Fix ESBJAVA-3461 - In the case when relative path is sent should be handled
                    if(log.isDebugEnabled()){
                        log.debug("Relative URL received for Location : " + oriURL, e);
                    }
                    urlContext = oriURL;
                }

                headers.remove(PassThroughConstants.LOCATION);
                String prfix = (String) outMsgCtx.getProperty(PassThroughConstants.SERVICE_PREFIX);
                if (prfix != null) {
                    if(urlContext != null && urlContext.startsWith("/")){
                        //Remove the preceding '/' character
                        urlContext = urlContext.substring(1);
                    }
                    headers.put(PassThroughConstants.LOCATION, prfix + urlContext);
                }

            }
            try {
                responseMsgCtx = outMsgCtx.getOperationContext().
                    getMessageContext(WSDL2Constants.MESSAGE_LABEL_IN);
                // fix for RM to work because of a soapAction and wsaAction conflict
                if (responseMsgCtx != null) {
                    responseMsgCtx.setSoapAction("");
                }
            } catch (AxisFault af) {
                log.error("Error getting IN message context from the operation context", af);
                return;
            }

            if (responseMsgCtx == null) {
                if (outMsgCtx.getOperationContext().isComplete()) {
                    if (log.isDebugEnabled()) {
                        log.debug("Error getting IN message context from the operation context. " +
                                "Possibly an RM terminate sequence message");
                    }
                    return;

                }
                responseMsgCtx = new MessageContext();
                responseMsgCtx.setOperationContext(outMsgCtx.getOperationContext());
            }
            responseMsgCtx.setProperty("PRE_LOCATION_HEADER",oriURL);
            // copy the important properties from the original message context
            responseMsgCtx.setProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONNECTION,
                    outMsgCtx.getProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONNECTION));
            responseMsgCtx.setProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONFIGURATION,
                    outMsgCtx.getProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONFIGURATION));
            responseMsgCtx.setProperty(AddressingConstants.DISABLE_ADDRESSING_FOR_IN_MESSAGES,
                    outMsgCtx.getProperty(AddressingConstants.DISABLE_ADDRESSING_FOR_IN_MESSAGES));
            responseMsgCtx.setProperty(PassThroughConstants.INTERNAL_EXCEPTION_ORIGIN,
                    outMsgCtx.getProperty(PassThroughConstants.INTERNAL_EXCEPTION_ORIGIN));

            responseMsgCtx.setServerSide(true);
            responseMsgCtx.setDoingREST(outMsgCtx.isDoingREST());
            responseMsgCtx.setProperty(MessageContext.TRANSPORT_IN, outMsgCtx
                    .getProperty(MessageContext.TRANSPORT_IN));
            responseMsgCtx.setTransportIn(outMsgCtx.getTransportIn());
            responseMsgCtx.setTransportOut(outMsgCtx.getTransportOut());

            //setting the responseMsgCtx PassThroughConstants.INVOKED_REST property to the one set inside PassThroughTransportUtils
            responseMsgCtx.setProperty(PassThroughConstants.INVOKED_REST, outMsgCtx.isDoingREST());
            responseMsgCtx.setProperty(PassThroughConstants.ORIGINAL_HTTP_SC, response.getStatus());
            responseMsgCtx.setProperty(PassThroughConstants.ORIGINAL_HTTP_REASON_PHRASE, response.getStatusLine());

            // set any transport headers received
            Set<Map.Entry<String, String>> headerEntries = response.getHeaders().entrySet();
            Map<String, String> headerMap = new TreeMap<String, String>(new Comparator<String>() {
                public int compare(String o1, String o2) {
                    return o1.compareToIgnoreCase(o2);
                }
            });

            for (Map.Entry<String, String> headerEntry : headerEntries) {
                if (headerMap.containsKey(headerEntry.getKey())) {
                    excessHeaders.put(headerEntry.getKey(), headerMap.get(headerEntry.getKey()));
                }
                headerMap.put(headerEntry.getKey(), headerEntry.getValue());
            }
            responseMsgCtx.setProperty(MessageContext.TRANSPORT_HEADERS, headerMap);
            responseMsgCtx.setProperty(NhttpConstants.EXCESS_TRANSPORT_HEADERS, excessHeaders);

            if (response.getStatus() == 202) {
                responseMsgCtx.setProperty(AddressingConstants.
                        DISABLE_ADDRESSING_FOR_OUT_MESSAGES, Boolean.TRUE);
                responseMsgCtx.setProperty(PassThroughConstants.MESSAGE_BUILDER_INVOKED, Boolean.FALSE);
                responseMsgCtx.setProperty(NhttpConstants.SC_ACCEPTED, Boolean.TRUE);
            }

            responseMsgCtx.setAxisMessage(outMsgCtx.getOperationContext().getAxisOperation().
                    getMessage(WSDLConstants.MESSAGE_LABEL_IN_VALUE));
            responseMsgCtx.setOperationContext(outMsgCtx.getOperationContext());
            responseMsgCtx.setConfigurationContext(outMsgCtx.getConfigurationContext());
            responseMsgCtx.setTo(null);

            responseMsgCtx.setProperty(PassThroughConstants.PASS_THROUGH_PIPE, response.getPipe());
            responseMsgCtx.setProperty(PassThroughConstants.PASS_THROUGH_TARGET_RESPONSE, response);
            responseMsgCtx.setProperty(SynapseDebugInfoHolder.SYNAPSE_WIRE_LOG_HOLDER_PROPERTY, response.getConnection()
                    .getContext().getAttribute(SynapseDebugInfoHolder.SYNAPSE_WIRE_LOG_HOLDER_PROPERTY));
            responseMsgCtx.setProperty(PassThroughConstants.PASS_THROUGH_TARGET_CONNECTION,
                    response.getConnection());
            responseMsgCtx.setProperty(CorrelationConstants.CORRELATION_ID,
                    outMsgCtx.getProperty(CorrelationConstants.CORRELATION_ID));
            for (String property : allowedResponseProperties) {
                responseMsgCtx.setProperty(property, outMsgCtx.getProperty(property));
            }
            responseMsgCtx.setProperty(PassThroughConstants.SYNAPSE_ARTIFACT_TYPE,
                                       outMsgCtx.getProperty(PassThroughConstants.SYNAPSE_ARTIFACT_TYPE));
            response.getConnection().getContext().setAttribute(PassThroughConstants.RESPONSE_MESSAGE_CONTEXT,
                                                               responseMsgCtx);
        }

        private void initTenantInfo() {

            CustomLogSetter.getInstance().clearThreadLocalContent();
            TenantInfoInitiator tenantInfoInitiator = TenantInfoInitiatorProvider.getTenantInfoInitiator();
            if (tenantInfoInitiator != null) {
                //check OUT_TRANSPORT_INFO is instanceOf ServerWorker to avoid possible classCastExceptions
                if (requestMessageContext.getProperty(Constants.OUT_TRANSPORT_INFO) instanceof ServerWorker) {
                    ServerWorker serverWorker = (ServerWorker) requestMessageContext.getProperty(Constants.OUT_TRANSPORT_INFO);
                    // Request received to Synapse is originated from through the HTTP transport
                    SourceRequest sourceRequest = serverWorker.getSourceRequest();
                    if (sourceRequest != null) {
                        tenantInfoInitiator.initTenantInfo(sourceRequest.getUri());
                        return;
                    }
                }
                tenantInfoInitiator.initTenantInfo();
            }
        }

        public void run() {

            initTenantInfo();
            if (responseMsgCtx == null) {
                cleanup();
                return;
            }
            // Mark the start of the request at the beginning of the worker thread
            response.getConnection().getContext().setAttribute(PassThroughConstants.CLIENT_WORKER_THREAD_STATUS,
                    PassThroughConstants.THREAD_STATUS_RUNNING);
            Object queuedTime =
                    response.getConnection().getContext().getAttribute(PassThroughConstants.CLIENT_WORKER_START_TIME);

            String expectedMaxQueueingTime = conf.getExpectedMaxQueueingTime();
            if (queuedTime != null && expectedMaxQueueingTime != null) {
                Long expectedMaxQueueingTimeInMillis = Long.parseLong(expectedMaxQueueingTime);
                Long clientWorkerQueuedTime = System.currentTimeMillis() - (Long) queuedTime;
                if (clientWorkerQueuedTime >= expectedMaxQueueingTimeInMillis) {
                    log.warn("Client worker thread queued time exceeds the expected max queueing time. Expected max " +
                            "queueing time : " + expectedMaxQueueingTimeInMillis + "ms. Actual queued time : " +
                            clientWorkerQueuedTime + "ms"+ ", CORRELATION_ID : "
                            + requestMessageContext.getProperty(CorrelationConstants.CORRELATION_ID));
                }

            }

            if (responseMsgCtx.getProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONNECTION) != null) {
                ((NHttpServerConnection) responseMsgCtx.getProperty(PassThroughConstants.PASS_THROUGH_SOURCE_CONNECTION)).
                           getContext().setAttribute(PassThroughConstants.CLIENT_WORKER_START_TIME, System.currentTimeMillis());
            }
            try {
                if (expectEntityBody) {
                	  String cType = response.getHeader(HTTP.CONTENT_TYPE);
                      if(cType == null){
                      	cType =  response.getHeader(HTTP.CONTENT_TYPE.toLowerCase());
                      }
                    String contentType;
                    if (cType != null) {
                        // This is the most common case - Most of the time servers send the Content-Type
                        contentType = cType;
                    } else {
                        // Server hasn't sent the header - Try to infer the content type
                        contentType = inferContentType();
                    }

                    responseMsgCtx.setProperty(Constants.Configuration.CONTENT_TYPE, contentType);

                    String charSetEnc = BuilderUtil.getCharSetEncoding(contentType);
                    if (charSetEnc == null) {
                        charSetEnc = MessageContext.DEFAULT_CHAR_SET_ENCODING;
                    }
                    if (contentType != null) {
                        responseMsgCtx.setProperty(
                                Constants.Configuration.CHARACTER_SET_ENCODING,
                                contentType.indexOf("charset") > 0 ?
                                charSetEnc : MessageContext.DEFAULT_CHAR_SET_ENCODING);
                        responseMsgCtx.removeProperty(PassThroughConstants.NO_ENTITY_BODY);
                    }

                    responseMsgCtx.setServerSide(false);
                    SOAPFactory fac = OMAbstractFactory.getSOAP11Factory();
                    SOAPEnvelope envelope = fac.getDefaultEnvelope();
                    try {
                        responseMsgCtx.setEnvelope(envelope);
                    } catch (AxisFault axisFault) {
                        log.error("Error setting SOAP envelope", axisFault);
                    }

                    responseMsgCtx.setServerSide(true);
                } else {
                    // there is no response entity-body
                    responseMsgCtx.setProperty(PassThroughConstants.NO_ENTITY_BODY, Boolean.TRUE);
                    responseMsgCtx.setEnvelope(new SOAP11Factory().getDefaultEnvelope());
                }

                // copy the HTTP status code as a message context property with the key HTTP_SC to be
                // used at the sender to set the proper status code when passing the message
                int statusCode = this.response.getStatus();
                responseMsgCtx.setProperty(PassThroughConstants.HTTP_SC, statusCode);
                responseMsgCtx.setProperty(PassThroughConstants.HTTP_SC_DESC, response.getStatusLine());
                if (statusCode >= 400) {
                    responseMsgCtx.setProperty(PassThroughConstants.FAULT_MESSAGE,
                            PassThroughConstants.TRUE);
                } /*else if (statusCode == 202 && responseMsgCtx.getOperationContext().isComplete()) {
                    // Handle out-only invocation scenario
                    responseMsgCtx.setProperty(PassThroughConstants.MESSAGE_BUILDER_INVOKED, Boolean.TRUE);
                }*/
                responseMsgCtx.setProperty(PassThroughConstants.NON_BLOCKING_TRANSPORT, true);

                // process response received
                try {
                    AxisEngine.receive(responseMsgCtx);
                } catch (AxisFault af) {
                    log.error("Fault processing response message through Axis2", af);
                    // This will be reached if an exception is thrown within an Axis2 handler
                    String errorMessage = "Fault processing response message through Axis2: " +
                            af.getMessage();
                    responseMsgCtx.setProperty(
                            NhttpConstants.SENDING_FAULT, Boolean.TRUE);
                    responseMsgCtx.setProperty(
                            NhttpConstants.ERROR_CODE, NhttpConstants.RESPONSE_PROCESSING_FAILURE);
                    responseMsgCtx.setProperty(
                            NhttpConstants.ERROR_MESSAGE, errorMessage.split("\n")[0]);
                    responseMsgCtx.setProperty(
                            NhttpConstants.ERROR_DETAIL, JavaUtils.stackToString(af));
                    responseMsgCtx.setProperty(
                            NhttpConstants.ERROR_EXCEPTION, af);
                    responseMsgCtx.getAxisOperation().getMessageReceiver().receive(responseMsgCtx);
                }

            } catch (AxisFault af) {
                log.error("Fault creating response SOAP envelope", af);
            } finally {
                cleanup();
            }
        }

        private String inferContentType() {
            //Check whether server sent Content-Type in different case
            Map<String,String> headers = response.getHeaders();
            for(String header : headers.keySet()){
                if(HTTP.CONTENT_TYPE.equalsIgnoreCase(header)){
                    return headers.get(header);
                }
            }
            String cType = response.getHeader("content-type");
            if (cType != null) {
                return cType;
            }
            cType = response.getHeader("Content-type");
            if (cType != null) {
                return cType;
            }

            // Try to get the content type from the message context
            Object cTypeProperty = responseMsgCtx.getProperty(PassThroughConstants.CONTENT_TYPE);
            if (cTypeProperty != null) {
                return cTypeProperty.toString();
            }
            // Try to get the content type from the axis configuration
            Parameter cTypeParam = targetConfiguration.getConfigurationContext().getAxisConfiguration().getParameter(
                    PassThroughConstants.CONTENT_TYPE);
            if (cTypeParam != null) {
                return cTypeParam.getValue().toString();
            }

            // When the response from backend does not have the body(Content-Length is 0 )
            // and Content-Type is not set; ESB should not do any modification to the response and pass-through as it is.
            boolean contentLengthHeaderPresent = false;
            String contentLengthHeader = headers.get(HTTP.CONTENT_LEN);

            if (contentLengthHeader != null) {
                contentLengthHeaderPresent = true;
            } else {
                for (String header : headers.keySet()) {
                    if (HTTP.CONTENT_LEN.equalsIgnoreCase(header)) {
                        contentLengthHeader = headers.get(header);
                        contentLengthHeaderPresent = true;
                        break;
                    }
                }
            }

            boolean transferEncodingHeaderPresent = headers.containsKey(HTTP.TRANSFER_ENCODING);

            if (!transferEncodingHeaderPresent) {

                for (String header : headers.keySet()) {
                    if (HTTP.TRANSFER_ENCODING.equalsIgnoreCase(header)) {
                        transferEncodingHeaderPresent = true;
                        break;
                    }
                }
            }

            if ((!contentLengthHeaderPresent && !transferEncodingHeaderPresent)
                    || "0".equals(contentLengthHeader)) {
                responseMsgCtx.setProperty(PassThroughConstants.NO_ENTITY_BODY, Boolean.TRUE);
                return null;
            }

            // Unable to determine the content type - Return default value
            return PassThroughConstants.DEFAULT_CONTENT_TYPE;
        }

        /**
         * Perform cleanup of ClientWorker
         */
        private void cleanup() {
            //clean threadLocal variables
            MessageContext.destroyCurrentMessageContext();
            TenantInfoInitiator tenantInfoInitiator = TenantInfoInitiatorProvider.getTenantInfoInitiator();
            if (tenantInfoInitiator != null) {
                tenantInfoInitiator.cleanTenantInfo();
            }
        }
    }