org.apache.hadoop.gateway.filter.PortMappingHelperHandler.java Source code

Introduction

Here is the source code for org.apache.hadoop.gateway.filter.PortMappingHelperHandler.java

Source

package org.apache.hadoop.gateway.filter;

import org.apache.commons.lang.StringUtils;
import org.apache.hadoop.gateway.GatewayMessages;
import org.apache.hadoop.gateway.config.GatewayConfig;
import org.apache.hadoop.gateway.i18n.messages.MessagesFactory;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.server.handler.HandlerWrapper;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.
 */

/**
 * This is a helper handler that adjusts the "target" patch of the request.
 * Used when Topology Port Mapping feature is used.
 * See KNOX-928
 *
 */
public class PortMappingHelperHandler extends HandlerWrapper {

    private static final GatewayMessages LOG = MessagesFactory.get(GatewayMessages.class);

    final GatewayConfig config;

    public PortMappingHelperHandler(final GatewayConfig config) {

        this.config = config;
    }

    @Override
    public void handle(final String target, final Request baseRequest, final HttpServletRequest request,
            final HttpServletResponse response) throws IOException, ServletException {

        // If Port Mapping feature enabled
        if (config.isGatewayPortMappingEnabled()) {
            int targetIndex;
            String context = "";
            String baseURI = baseRequest.getUri().toString();

            // extract the gateway specific part i.e. {/gatewayName/}
            String originalContextPath = "";
            targetIndex = StringUtils.ordinalIndexOf(target, "/", 2);

            // Match found e.g. /{string}/
            if (targetIndex > 0) {
                originalContextPath = target.substring(0, targetIndex + 1);
            } else if (targetIndex == -1) {
                targetIndex = StringUtils.ordinalIndexOf(target, "/", 1);
                // For cases "/" and "/hive"
                if (targetIndex == 0) {
                    originalContextPath = target;
                }
            }

            // Match "/{gatewayName}/{topologyName/foo" or "/".
            // There could be a case where content is served from the root
            // i.e. https://host:port/

            if (!baseURI.startsWith(originalContextPath)) {
                final int index = StringUtils.ordinalIndexOf(baseURI, "/", 3);
                if (index > 0) {
                    context = baseURI.substring(0, index);
                }
            }

            if (!StringUtils.isBlank(context)) {
                LOG.topologyPortMappingAddContext(target, context + target);
            }
            // Move on to the next handler in chain with updated path
            super.handle(context + target, baseRequest, request, response);
        } else {
            super.handle(target, baseRequest, request, response);
        }

    }
}