/* * Copyright 2018-2019 the original author or authors. * * 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 * * https://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.springframework.cloud.stream.binder.kafka.streams; import org.aopalliance.intercept.MethodInterceptor; import org.aopalliance.intercept.MethodInvocation; import org.apache.kafka.streams.kstream.GlobalKTable; import org.springframework.aop.framework.ProxyFactory; import org.springframework.cloud.stream.binder.ConsumerProperties; import org.springframework.cloud.stream.binding.AbstractBindingTargetFactory; import org.springframework.cloud.stream.config.BindingProperties; import org.springframework.cloud.stream.config.BindingServiceProperties; import org.springframework.util.Assert; /** * {@link org.springframework.cloud.stream.binding.BindingTargetFactory} for * {@link GlobalKTable} * * Input bindings are only created as output bindings on GlobalKTable are not allowed. * * @author Soby Chacko * @since 2.1.0 */ public class GlobalKTableBoundElementFactory extends AbstractBindingTargetFactory<GlobalKTable> { private final BindingServiceProperties bindingServiceProperties; private final EncodingDecodingBindAdviceHandler encodingDecodingBindAdviceHandler; GlobalKTableBoundElementFactory(BindingServiceProperties bindingServiceProperties, EncodingDecodingBindAdviceHandler encodingDecodingBindAdviceHandler) { super(GlobalKTable.class); this.bindingServiceProperties = bindingServiceProperties; this.encodingDecodingBindAdviceHandler = encodingDecodingBindAdviceHandler; } @Override public GlobalKTable createInput(String name) { BindingProperties bindingProperties = this.bindingServiceProperties.getBindingProperties(name); ConsumerProperties consumerProperties = bindingProperties.getConsumer(); if (consumerProperties == null) { consumerProperties = this.bindingServiceProperties.getConsumerProperties(name); consumerProperties.setUseNativeDecoding(true); } else { if (!encodingDecodingBindAdviceHandler.isDecodingSettingProvided()) { consumerProperties.setUseNativeDecoding(true); } } // Always set multiplex to true in the kafka streams binder consumerProperties.setMultiplex(true); // @checkstyle:off GlobalKTableBoundElementFactory.GlobalKTableWrapperHandler wrapper = new GlobalKTableBoundElementFactory.GlobalKTableWrapperHandler(); // @checkstyle:on ProxyFactory proxyFactory = new ProxyFactory( GlobalKTableBoundElementFactory.GlobalKTableWrapper.class, GlobalKTable.class); proxyFactory.addAdvice(wrapper); return (GlobalKTable) proxyFactory.getProxy(); } @Override public GlobalKTable createOutput(String name) { throw new UnsupportedOperationException( "Outbound operations are not allowed on target type GlobalKTable"); } /** * Wrapper for GlobalKTable proxy. */ public interface GlobalKTableWrapper { void wrap(GlobalKTable<Object, Object> delegate); } private static class GlobalKTableWrapperHandler implements GlobalKTableBoundElementFactory.GlobalKTableWrapper, MethodInterceptor { private GlobalKTable<Object, Object> delegate; public void wrap(GlobalKTable<Object, Object> delegate) { Assert.notNull(delegate, "delegate cannot be null"); if (this.delegate == null) { this.delegate = delegate; } } @Override public Object invoke(MethodInvocation methodInvocation) throws Throwable { if (methodInvocation.getMethod().getDeclaringClass() .equals(GlobalKTable.class)) { Assert.notNull(this.delegate, "Trying to prepareConsumerBinding " + methodInvocation.getMethod() + " but no delegate has been set."); return methodInvocation.getMethod().invoke(this.delegate, methodInvocation.getArguments()); } else if (methodInvocation.getMethod().getDeclaringClass() .equals(GlobalKTableBoundElementFactory.GlobalKTableWrapper.class)) { return methodInvocation.getMethod().invoke(this, methodInvocation.getArguments()); } else { throw new IllegalStateException( "Only GlobalKTable method invocations are permitted"); } } } }