Replace propAccessorInjector with the SpelPAReg

After changing the `propertyAccessorInjector` `BeanPostProcessor`
just to a simple `InitializingBean` there is no guarantee which bean
will be accessed from the autowire phase.
There are some cases like `@PostConstruct` on the `@Configuration`
wich may be called before this new `propertyAccessorInjector` bean
and we end up with `EvaluationContext` not supplied with additional
`PropertyAccessors`

* For proper `IntegrationEvaluationContextFactoryBean` initialization
add `SpelPropertyAccessorRegistrar` for custom `PA` configuration
* Remove `propertyAccessorInjector` bean altogether
* Resolve deprecation in the `BindingServiceConfiguration`
* Modify `SpelExpressionConverterConfigurationTests` to confirm that
even `@PostConstruct` on `@Configuration` works as expected

Resolves #1178

spring-cloud-stream/src/main/java/org/springframework/cloud/stream/config/BindingServiceConfiguration.java

@@ -16,7 +16,6 @@
 
 package org.springframework.cloud.stream.config;
 
-import java.beans.Introspector;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -32,7 +31,6 @@ import org.springframework.cloud.stream.binder.BinderFactory;
 import org.springframework.cloud.stream.binding.AbstractBindingTargetFactory;
 import org.springframework.cloud.stream.binding.Bindable;
 import org.springframework.cloud.stream.binding.BinderAwareChannelResolver;
-import org.springframework.cloud.stream.binding.BinderAwareRouterBeanPostProcessor;
 import org.springframework.cloud.stream.binding.BindingService;
 import org.springframework.cloud.stream.binding.CompositeMessageChannelConfigurer;
 import org.springframework.cloud.stream.binding.ContextStartAfterRefreshListener;
@@ -51,15 +49,12 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.DependsOn;
 import org.springframework.context.annotation.Import;
 import org.springframework.context.annotation.Role;
-import org.springframework.expression.PropertyAccessor;
 import org.springframework.integration.channel.DirectChannel;
 import org.springframework.integration.channel.PublishSubscribeChannel;
 import org.springframework.integration.config.HandlerMethodArgumentResolversHolder;
-import org.springframework.integration.config.IntegrationEvaluationContextFactoryBean;
 import org.springframework.integration.context.IntegrationContextUtils;
 import org.springframework.integration.handler.AbstractReplyProducingMessageHandler;
 import org.springframework.integration.handler.BridgeHandler;
-import org.springframework.integration.json.JsonPropertyAccessor;
 import org.springframework.integration.router.AbstractMappingMessageRouter;
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.MessageChannel;
@@ -68,7 +63,6 @@ import org.springframework.messaging.core.DestinationResolver;
 import org.springframework.messaging.handler.annotation.support.DefaultMessageHandlerMethodFactory;
 import org.springframework.messaging.handler.annotation.support.MessageHandlerMethodFactory;
 import org.springframework.scheduling.TaskScheduler;
-import org.springframework.tuple.spel.TuplePropertyAccessor;
 import org.springframework.util.CollectionUtils;
 
 /**
@@ -83,7 +77,6 @@ import org.springframework.util.CollectionUtils;
  * @author Artem Bilan
  * @author Oleg Zhurakousky
  */
-@SuppressWarnings("deprecation")
 @Configuration
 @EnableConfigurationProperties({ BindingServiceProperties.class, SpringIntegrationProperties.class })
 @Import(ContentTypeConfiguration.class)
@@ -216,27 +209,12 @@ public class BindingServiceConfiguration {
 
 	@Bean
 	@ConditionalOnMissingBean
-	public BinderAwareRouterBeanPostProcessor binderAwareRouterBeanPostProcessor(@Autowired(required=false) AbstractMappingMessageRouter[] routers,
+	@SuppressWarnings("deprecation")
+	public org.springframework.cloud.stream.binding.BinderAwareRouterBeanPostProcessor binderAwareRouterBeanPostProcessor(
+			@Autowired(required=false) AbstractMappingMessageRouter[] routers,
 			@Autowired(required=false)DestinationResolver<MessageChannel> channelResolver) {
-		return new BinderAwareRouterBeanPostProcessor(routers, channelResolver);
-	}
 
-	@Bean
-	public InitializingBean propertyAccessorInjector(IntegrationEvaluationContextFactoryBean[] iecfbs) {
-		return new InitializingBean() {
-			@Override
-			public void afterPropertiesSet() throws Exception {
-				TuplePropertyAccessor tpa = new TuplePropertyAccessor();
-				JsonPropertyAccessor jpa = new JsonPropertyAccessor();
-				if (iecfbs != null) {
-					for (IntegrationEvaluationContextFactoryBean iecfb : iecfbs) {
-						Map<String, PropertyAccessor> factoryBeanAccessors = iecfb.getPropertyAccessors();
-						factoryBeanAccessors.put(Introspector.decapitalize(tpa.getClass().getSimpleName()), tpa);
-						factoryBeanAccessors.put(Introspector.decapitalize(jpa.getClass().getSimpleName()), jpa);
-					}
-				}
-			}
-		};
+		return new org.springframework.cloud.stream.binding.BinderAwareRouterBeanPostProcessor(routers, channelResolver);
 	}
 
 	@Bean
@@ -254,4 +232,5 @@ public class BindingServiceConfiguration {
 			}
 		};
 	}
+
 }

spring-cloud-stream/src/main/java/org/springframework/cloud/stream/config/SpelExpressionConverterConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2018 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.
@@ -16,6 +16,8 @@
 
 package org.springframework.cloud.stream.config;
 
+import java.beans.Introspector;
+
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.beans.factory.config.BeanDefinition;
@@ -32,16 +34,36 @@ import org.springframework.expression.spel.standard.SpelExpression;
 import org.springframework.expression.spel.standard.SpelExpressionParser;
 import org.springframework.integration.config.IntegrationConverter;
 import org.springframework.integration.context.IntegrationContextUtils;
+import org.springframework.integration.expression.SpelPropertyAccessorRegistrar;
+import org.springframework.integration.json.JsonPropertyAccessor;
+import org.springframework.tuple.spel.TuplePropertyAccessor;
 
 /**
  * Adds a Converter from String to SpEL Expression in the context.
  *
  * @author Eric Bottard
+ * @author Artem Bilan
  */
 @Configuration
 @Role(BeanDefinition.ROLE_INFRASTRUCTURE)
 public class SpelExpressionConverterConfiguration {
 
+	/**
+	 * Provide a {@link SpelPropertyAccessorRegistrar} supplied
+	 * with the {@link JsonPropertyAccessor} and {@link TuplePropertyAccessor}.
+	 * This bean is used to customize an
+	 * {@link org.springframework.integration.config.IntegrationEvaluationContextFactoryBean}.
+	 * for additional {@link org.springframework.expression.PropertyAccessor}s.
+	 * @return the SpelPropertyAccessorRegistrar bean
+	 * @see org.springframework.integration.config.IntegrationEvaluationContextFactoryBean
+	 */
+	@Bean
+	public static SpelPropertyAccessorRegistrar spelPropertyAccessorRegistrar() {
+		return new SpelPropertyAccessorRegistrar()
+				.add(Introspector.decapitalize(JsonPropertyAccessor.class.getSimpleName()), new JsonPropertyAccessor())
+				.add(Introspector.decapitalize(TuplePropertyAccessor.class.getSimpleName()), new TuplePropertyAccessor());
+	}
+
 	@Bean
 	@ConfigurationPropertiesBinding
 	@IntegrationConverter

spring-cloud-stream/src/test/java/org/springframework/cloud/stream/config/SpelExpressionConverterConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015 the original author or authors.
+ * Copyright 2015-2018 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.
@@ -16,9 +16,16 @@
 
 package org.springframework.cloud.stream.config;
 
+import java.util.List;
+
+import javax.annotation.PostConstruct;
+
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.BeanFactoryAware;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.context.properties.ConfigurationProperties;
@@ -26,9 +33,15 @@ import org.springframework.boot.context.properties.EnableConfigurationProperties
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.cloud.stream.annotation.EnableBinding;
 import org.springframework.cloud.stream.utils.MockBinderRegistryConfiguration;
+import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.Import;
+import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.Expression;
+import org.springframework.expression.PropertyAccessor;
+import org.springframework.integration.expression.ExpressionUtils;
+import org.springframework.integration.json.JsonPropertyAccessor;
+import org.springframework.integration.test.util.TestUtils;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -37,6 +50,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  * Tests for SpelExpressionConverterConfiguration.
  *
  * @author Eric Bottard
+ * @author Artem Bilan
  */
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringBootTest(classes = SpelExpressionConverterConfigurationTests.Config.class, properties = "expression: a.b")
@@ -45,9 +59,28 @@ public class SpelExpressionConverterConfigurationTests {
 	@Autowired
 	private Pojo pojo;
 
+	@Autowired
+	private EvaluationContext evaluationContext;
+
+	@Autowired
+	private Config config;
+
+
 	@Test
+	@SuppressWarnings("unchecked")
 	public void converterCorrectlyInstalled() {
-		assertThat(pojo.getExpression().getValue("{\"a\": {\"b\": 5}}").toString()).isEqualTo("5");
+		Expression expression = pojo.getExpression();
+		assertThat(expression.getValue("{\"a\": {\"b\": 5}}").toString()).isEqualTo("5");
+
+		List<PropertyAccessor> propertyAccessors =
+				TestUtils.getPropertyValue(this.evaluationContext, "propertyAccessors", List.class);
+
+		assertThat(propertyAccessors).hasAtLeastOneElementOfType(JsonPropertyAccessor.class);
+
+		propertyAccessors =
+				TestUtils.getPropertyValue(this.config.evaluationContext, "propertyAccessors", List.class);
+
+		assertThat(propertyAccessors).hasAtLeastOneElementOfType(JsonPropertyAccessor.class);
 	}
 
 	@ConfigurationProperties
@@ -69,7 +102,26 @@ public class SpelExpressionConverterConfigurationTests {
 	@EnableAutoConfiguration
 	@Import(MockBinderRegistryConfiguration.class)
 	@EnableConfigurationProperties(Pojo.class)
-	public static class Config {
+	public static class Config implements BeanFactoryAware {
+
+		private BeanFactory beanFactory;
+
+		private EvaluationContext evaluationContext;
+
+		@Override
+		public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
+			this.beanFactory = beanFactory;
+		}
+
+		@Bean
+		public EvaluationContext evaluationContext() {
+			return ExpressionUtils.createStandardEvaluationContext(this.beanFactory);
+		}
+
+		@PostConstruct
+		public void setup() {
+			this.evaluationContext = ExpressionUtils.createStandardEvaluationContext(this.beanFactory);
+		}
 
 	}