# PassThroughConfiguration.java

    /*
    *  Copyright (c) 2005-2010, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
    *
    *  WSO2 Inc. 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.synapse.transport.passthru.config;

    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.http.params.HttpConnectionParams;
    import org.apache.synapse.transport.passthru.PassThroughConstants;
    import org.apache.synapse.transport.util.ConfigurationBuilderUtil;

    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.IOException;
    import java.io.InputStream;
    import java.util.Properties;

    /**
     * This class encapsulates pass-through http transport tuning configurations specified via a
     * configurations file or system properties.
     */
    public class PassThroughConfiguration {

        /**
         * Default tuning parameter values
         */
        private static final int DEFAULT_WORKER_POOL_SIZE_CORE       = 40;
        private static final boolean CLOSE_SOCKET_ON_ENDPOINT_TIMEOUT = false;
        private static final int DEFAULT_WORKER_POOL_SIZE_MAX        = 200;
        private static final int DEFAULT_WORKER_THREAD_KEEPALIVE_SEC = 60;
        private static final int DEFAULT_WORKER_POOL_QUEUE_LENGTH    = -1;
        private static final int DEFAULT_IO_BUFFER_SIZE              = 8 * 1024;
        private static final int DEFAULT_IO_THREADS_PER_REACTOR      =
                                                             Runtime.getRuntime().availableProcessors();
        private static final int DEFAULT_MAX_ACTIVE_CON = -1;
        private static final int DEFAULT_LISTENER_SHUTDOWN_WAIT_TIME = 0;
        private static final int DEFAULT_CONNECTION_GRACE_TIME = 10000;

        private static final String EXPECTED_MAX_QUEUEING_TIME_DEFAULT = "1000";
        private Boolean isKeepAliveDisabled = null;

        private Boolean isConsumeAndDiscard = true;

        private Boolean isConsumeAndDiscardBySecondaryWorkerPool = true;

        //additional rest dispatch handlers
        private static final String REST_DISPATCHER_SERVICE="rest.dispatcher.service";
        // URI configurations that determine if it requires custom rest dispatcher
        private static final String REST_URI_API_REGEX = "rest_uri_api_regex";
        private static final String REST_URI_PROXY_REGEX = "rest_uri_proxy_regex";
        // properties which are allowed to be directly pass through from request context to response context explicitly
        private static final String ALLOWED_RESPONSE_PROPERTIES = "allowed_response_properties";

        /** Reverse proxy mode is enabled or not */
        private Boolean reverseProxyMode = null;

        /** Enables graceful termination for TLS connection */
        private Boolean isTLSGracefulConnectionTerminationEnabled = null;

        /** Default Synapse service name */
        private String passThroughDefaultServiceName = null;

        private static final Log log = LogFactory.getLog(PassThroughConfiguration.class);

        private static PassThroughConfiguration _instance = new PassThroughConfiguration();

        private Properties props;

        private PassThroughConfiguration() {
            try {
                props = loadProperties("passthru-http.properties");
            } catch (Exception ignored) {}
        }

        public static PassThroughConfiguration getInstance() {
            return _instance;
        }

        public int getWorkerPoolCoreSize() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.WORKER_POOL_SIZE_CORE,
                    DEFAULT_WORKER_POOL_SIZE_CORE, props);
        }
        public int getSecondaryWorkerPoolCoreSize() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.SECONDARY_WORKER_POOL_SIZE_CORE,
                    DEFAULT_WORKER_POOL_SIZE_CORE, props);
        }

        public int getWorkerPoolMaxSize() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.WORKER_POOL_SIZE_MAX,
                    DEFAULT_WORKER_POOL_SIZE_MAX, props);
        }
        public int getSecondaryWorkerPoolMaxSize() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.SECONDARY_WORKER_POOL_SIZE_MAX,
                    DEFAULT_WORKER_POOL_SIZE_MAX, props);
        }

        public int getWorkerThreadKeepaliveSec() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.WORKER_THREAD_KEEP_ALIVE_SEC,
                    DEFAULT_WORKER_THREAD_KEEPALIVE_SEC, props);
        }

        public int getSecondaryWorkerThreadKeepaliveSec() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.SECONDARY_WORKER_THREAD_KEEPALIVE_SEC,
                    DEFAULT_WORKER_THREAD_KEEPALIVE_SEC, props);
        }

        public int getWorkerPoolQueueLen() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.WORKER_POOL_QUEUE_LENGTH,
                    DEFAULT_WORKER_POOL_QUEUE_LENGTH, props);
        }

        public int getSecondaryWorkerPoolQueueLen() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.SECONDARY_WORKER_POOL_QUEUE_LENGTH,
                    DEFAULT_WORKER_POOL_QUEUE_LENGTH, props);
        }

        public int getIOThreadsPerReactor() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.IO_THREADS_PER_REACTOR,
                    DEFAULT_IO_THREADS_PER_REACTOR, props);
        }

        public int getIOBufferSize() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.IO_BUFFER_SIZE,
                    DEFAULT_IO_BUFFER_SIZE, props);
        }

        public boolean isKeepAliveDisabled() {
            if (isKeepAliveDisabled == null) {
                isKeepAliveDisabled =
                        ConfigurationBuilderUtil.getBooleanProperty(PassThroughConfigPNames.DISABLE_KEEPALIVE,
                                false, props);
            }
            return isKeepAliveDisabled;
        }

        public boolean isCloseSocketOnEndpointTimeout() {
            return ConfigurationBuilderUtil.getBooleanProperty(PassThroughConfigPNames.CLOSE_SOCKET_ON_ENDPOINT_TIMEOUT
                    , CLOSE_SOCKET_ON_ENDPOINT_TIMEOUT, props);
        }

        public boolean isTLSGracefulConnectionTerminationEnabled() {
            if (isTLSGracefulConnectionTerminationEnabled == null) {
                isTLSGracefulConnectionTerminationEnabled = getBooleanProperty(
                        PassThroughConfigPNames.TLS_GRACEFUL_CONNECTION_TERMINATION, true);
            }
            return isTLSGracefulConnectionTerminationEnabled;
        }

        public boolean isConsumeAndDiscard() {
            isConsumeAndDiscard =
                        ConfigurationBuilderUtil.getBooleanProperty(PassThroughConfigPNames.CONSUME_AND_DISCARD,
                                true, props);
            return isConsumeAndDiscard;
        }

        public boolean isConsumeAndDiscardBySecondaryWorkerPool() {
            isConsumeAndDiscardBySecondaryWorkerPool =
                    ConfigurationBuilderUtil.getBooleanProperty(
                            PassThroughConfigPNames.CONSUME_AND_DISCARD_BY_SECONDARY_POOL, true, props);
            return isConsumeAndDiscardBySecondaryWorkerPool;
        }

        public int getMaxActiveConnections() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.C_MAX_ACTIVE, DEFAULT_MAX_ACTIVE_CON,
                    props);
        }
        public int getListenerShutdownWaitTime() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames
                            .TRANSPORT_LISTENER_SHUTDOWN_WAIT_TIME_SEC, DEFAULT_LISTENER_SHUTDOWN_WAIT_TIME, props) * 1000;
        }

        public boolean isPreserveUserAgentHeader() {
            return ConfigurationBuilderUtil.getBooleanProperty(PassThroughConfigPNames.USER_AGENT_HEADER_PRESERVE,
                    false, props);
        }

        public boolean isPreserveServerHeader() {
            return ConfigurationBuilderUtil.getBooleanProperty(PassThroughConfigPNames.SERVER_HEADER_PRESERVE,
                    false, props);
        }

        public boolean isForcedXmlMessageValidationEnabled() {
            return ConfigurationBuilderUtil.getBooleanProperty(PassThroughConstants.FORCE_XML_MESSAGE_VALIDATION,
                    false, props);
        }

        public boolean isForcedJSONMessageValidationEnabled() {
            return ConfigurationBuilderUtil.getBooleanProperty(PassThroughConstants.FORCE_JSON_MESSAGE_VALIDATION,
                    false, props);
        }

        public String getPreserveHttpHeaders() {
            return ConfigurationBuilderUtil.getStringProperty(PassThroughConfigPNames.HTTP_HEADERS_PRESERVE,
                    "", props);
        }

        public String getResponsePreseveHttpHeaders() {
            return ConfigurationBuilderUtil.getStringProperty(PassThroughConfigPNames.HTTP_RESPONSE_HEADERS_PRESERVE,
                    "", props);
        }

        public boolean isServiceListBlocked() {
            return getBooleanProperty(PassThroughConfigPNames.BLOCK_SERVICE_LIST, true);
        }

        public int getConnectionIdleTime() {

            int idleTime;
            // Giving higher priority for grace time if it is configured, than for the configured idle time
            if (ConfigurationBuilderUtil.isIntPropertyConfigured(PassThroughConfigPNames.CONNECTION_GRACE_TIME, props)) {
                idleTime = getIdleTimeFromGraceTime();
            } else {
                // Setting idle time if it is configured, if not, using the default grace time to calculate idle time
                idleTime = ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.CONNECTION_IDLE_TIME,
                        getIdleTimeFromGraceTime(), props);
            }

            if (idleTime < 0) {
                return 0;
            }
            return idleTime;
        }
        public int getMaximumConnectionLifespan() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.MAXIMUM_CONNECTION_LIFESPAN,
                    Integer.MAX_VALUE, props);
        }
        public int getConnectionGraceTime() {
            return ConfigurationBuilderUtil.getIntProperty(PassThroughConfigPNames.CONNECTION_GRACE_TIME,
                    DEFAULT_CONNECTION_GRACE_TIME, props);
        }

        /**
         * For the default value, grace time is reduced to avoid connection being used at the moment it is being closed.
         * @return default connection idle time
         */
        private int getIdleTimeFromGraceTime() {
            return ConfigurationBuilderUtil
                    .getIntProperty(HttpConnectionParams.SO_TIMEOUT, 60000, props) - getConnectionGraceTime();
        }

        public String getCorrelationHeaderName() {
            return ConfigurationBuilderUtil.getStringProperty(PassThroughConfigPNames.CORRELATION_HEADER_NAME_PROPERTY,
                    PassThroughConstants.CORRELATION_DEFAULT_HEADER, props);
        }

        public String getExpectedMaxQueueingTime() {
            return getStringProperty(PassThroughConfigPNames.EXPECTED_MAX_QUEUEING_TIME,
                    EXPECTED_MAX_QUEUEING_TIME_DEFAULT);
        }

        public Long getExpectedMaxQueueingTimeForMessageDiscardWorker() {
            String expectedMaxQueuingTime = getStringProperty(
                    PassThroughConfigPNames.EXPECTED_MAX_QUEUEING_TIME_FOR_MESSAGE_DISCARD_WORKER,
                    EXPECTED_MAX_QUEUEING_TIME_DEFAULT);
            Long convertedExpectedMaxQueuingTime;
            try {
                convertedExpectedMaxQueuingTime = Long.parseLong(expectedMaxQueuingTime);
            } catch (NumberFormatException exception) {
                log.warn("Invalid value for the expected max queuing time for message discard worker. Expected max "
                        + "queuing time should be a long value. "
                        + "Using the default value " + EXPECTED_MAX_QUEUEING_TIME_DEFAULT);
                convertedExpectedMaxQueuingTime = Long.parseLong(EXPECTED_MAX_QUEUEING_TIME_DEFAULT);
            }
            return convertedExpectedMaxQueuingTime;
        }

        /**
         * Loads the properties from a given property file path
         *
         * @param filePath Path of the property file
         * @return Properties loaded from given file
         */
        private static Properties loadProperties(String filePath) {

        	 Properties properties = new Properties();
             ClassLoader cl = Thread.currentThread().getContextClassLoader();

             if (log.isDebugEnabled()) {
                 log.debug("Loading the file '" + filePath + "' from classpath");
             }

             InputStream in  = null;

             //if we reach to this assume that the we may have to looking to the customer provided external location for the
             //given properties
     		if (System.getProperty(PassThroughConstants.CONF_LOCATION) != null) {
     			try {
     				in = new FileInputStream(System.getProperty(PassThroughConstants.CONF_LOCATION) + File.separator + filePath);
     			} catch (FileNotFoundException e) {
     				String msg = "Error loading properties from a file at from the System defined location: " + filePath;
     				log.warn(msg);
     			}
     		}

             if (in == null) {
             	in = cl.getResourceAsStream(filePath);
                 if (log.isDebugEnabled()) {
                     log.debug("Unable to load file  '" + filePath + "'");
                 }

                 filePath = "conf" + File.separatorChar + filePath;
                 if (log.isDebugEnabled()) {
                     log.debug("Loading the file '" + filePath + "'");
                 }

                 in = cl.getResourceAsStream(filePath);
                 if (in == null) {
                     if (log.isDebugEnabled()) {
                         log.debug("Unable to load file  '" + filePath + "'");
                     }
                 }
             }
             if (in != null) {
                 try {
                     properties.load(in);
                 } catch (IOException e) {
                     String msg = "Error loading properties from a file at : " + filePath;
                     log.error(msg, e);
                 }
             }
             return properties;
        }

        public Boolean getBooleanProperty(String name) {
            return ConfigurationBuilderUtil.getBooleanProperty(name, null, props);
        }

        public Boolean getBooleanProperty(String name, Boolean def) {
            return ConfigurationBuilderUtil.getBooleanProperty(name, def, props);
        }

        public Integer getIntProperty(String name, Integer def) {
            return ConfigurationBuilderUtil.getIntProperty(name, def, props);
        }

        public String getStringProperty(String name, String def) {
            return ConfigurationBuilderUtil.getStringProperty(name, def, props);
        }

        public String getRESTDispatchService() {
            return ConfigurationBuilderUtil.getStringProperty(REST_DISPATCHER_SERVICE, "", props);
        }

        public String getRestUriApiRegex() {
            return ConfigurationBuilderUtil.getStringProperty(REST_URI_API_REGEX, "", props);
        }

        public String getRestUriProxyRegex() {
            return ConfigurationBuilderUtil.getStringProperty(REST_URI_PROXY_REGEX, "", props);
        }

        public boolean isListeningIOReactorShared() {
            return ConfigurationBuilderUtil
                    .getBooleanProperty(PassThroughConfigPNames.HTTP_LISTENING_IO_REACTOR_SHARING_ENABLE, false, props);
        }

        public String getAllowedResponseProperties() {
            return ConfigurationBuilderUtil.getStringProperty(ALLOWED_RESPONSE_PROPERTIES, null, props);
        }

        /**
         * Check for reverse proxy mode
         *
         * @return whether reverse proxy mode is enabled
         */
        public boolean isReverseProxyMode() {
            if (reverseProxyMode == null) {
                reverseProxyMode = Boolean.parseBoolean(System.getProperty("reverseProxyMode"));
            }
            return reverseProxyMode;
        }

        /**
         * Get the default synapse service name
         *
         * @return default synapse service name
         */
        public String getPassThroughDefaultServiceName() {
            if (passThroughDefaultServiceName == null) {
                passThroughDefaultServiceName = getStringProperty("passthru.default.service", "__SynapseService");
            }
            return passThroughDefaultServiceName;
        }

        /**
         * Get the value of the property to ignore case-sensitive headers from excess headers
         *
         * @return Value of the property
         */
        public boolean isIgnoreCaseSensitiveHeaders() {
            return ConfigurationBuilderUtil.getBooleanProperty(PassThroughConfigPNames.IGNORE_CASE_SENSITIVE_HEADERS,
                    false, props);
        }
    }