| /** |
| * 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.hadoop.gateway.filter.rewrite.impl; |
| |
| import org.apache.hadoop.gateway.filter.rewrite.api.FrontendFunctionDescriptor; |
| import org.apache.hadoop.gateway.filter.rewrite.api.UrlRewriteEnvironment; |
| import org.apache.hadoop.gateway.filter.rewrite.i18n.UrlRewriteResources; |
| import org.apache.hadoop.gateway.filter.rewrite.spi.UrlRewriteContext; |
| import org.apache.hadoop.gateway.filter.rewrite.spi.UrlRewriteFunctionProcessor; |
| import org.apache.hadoop.gateway.filter.rewrite.spi.UrlRewriteResolver; |
| import org.apache.hadoop.gateway.i18n.resources.ResourcesFactory; |
| import org.apache.hadoop.gateway.services.GatewayServices; |
| |
| import java.net.URI; |
| import java.util.Arrays; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| |
| public class FrontendFunctionProcessor implements UrlRewriteFunctionProcessor<FrontendFunctionDescriptor> { |
| |
| private static UrlRewriteResources RES = ResourcesFactory.get( UrlRewriteResources.class ); |
| |
| private Map<String,UrlRewriteResolver> resolvers; |
| |
| @Override |
| public String name() { |
| return FrontendFunctionDescriptor.FUNCTION_NAME; |
| } |
| |
| @Override |
| public void initialize( UrlRewriteEnvironment environment, FrontendFunctionDescriptor descriptor ) throws Exception { |
| if( environment == null ) { |
| throw new IllegalArgumentException( "environment==null" ); |
| } |
| URI frontend = environment.getAttribute( FrontendFunctionDescriptor.FRONTEND_URI_ATTRIBUTE ); |
| resolvers = new HashMap<String,UrlRewriteResolver>(); |
| if( frontend == null ) { |
| resolvers.put( "url", new ParamResolver( "gateway.url" ) ); |
| resolvers.put( "addr", new ParamResolver( "gateway.addr" ) ); |
| resolvers.put( "scheme", new ParamResolver( "gateway.scheme" ) ); |
| resolvers.put( "host", new ParamResolver( "gateway.host" ) ); |
| resolvers.put( "port", new ParamResolver( "gateway.port" ) ); |
| resolvers.put( "path", new ParamResolver( "gateway.path" ) ); |
| } else { |
| resolvers.put( "url", new FixedResolver( frontend.toString() ) ); |
| resolvers.put( "addr", new FixedResolver( frontend.getHost() + ":" + frontend.getPort() ) ); |
| resolvers.put( "scheme", new FixedResolver( frontend.getScheme() ) ); |
| resolvers.put( "host", new FixedResolver( frontend.getHost() ) ); |
| resolvers.put( "port", new FixedResolver( Integer.toString( frontend.getPort() ) ) ); |
| resolvers.put( "path", new FixedResolver( frontend.getPath() ) ); |
| } |
| resolvers.put( "topology", new FixedResolver( (String)environment.getAttribute(GatewayServices.GATEWAY_CLUSTER_ATTRIBUTE) ) ); |
| resolvers.put( "address", resolvers.get( "addr" ) ); |
| } |
| |
| @Override |
| public void destroy() throws Exception { |
| resolvers.clear(); |
| } |
| |
| @Override |
| public List<String> resolve( UrlRewriteContext context, List<String> parameters ) throws Exception { |
| String parameter = "url"; |
| if( parameters != null && parameters.size() > 0 ) { |
| String first = parameters.get( 0 ); |
| if( first != null ) { |
| parameter = first; |
| } |
| } |
| parameter = parameter.trim().toLowerCase(); |
| UrlRewriteResolver resolver = resolvers.get( parameter ); |
| if( resolver == null ) { |
| throw new IllegalArgumentException( RES.invalidFrontendFunctionParameter( parameter ) ); |
| } |
| List<String> results = resolver.resolve( context, parameters ); |
| return results; |
| } |
| |
| private class ParamResolver implements UrlRewriteResolver { |
| |
| private String paramName; |
| |
| private ParamResolver( String paramName ) { |
| this.paramName = paramName; |
| } |
| |
| @Override |
| public List<String> resolve( UrlRewriteContext context, List<String> parameter ) throws Exception { |
| return context.getParameters().resolve( paramName ); |
| } |
| |
| } |
| |
| private class FixedResolver implements UrlRewriteResolver { |
| |
| private List<String> fixedValues; |
| |
| private FixedResolver( String... fixedValues ) { |
| this.fixedValues = Arrays.asList( fixedValues ); |
| } |
| |
| @Override |
| public List<String> resolve( UrlRewriteContext context, List<String> parameter ) throws Exception { |
| return fixedValues; |
| } |
| |
| } |
| |
| } |