1. 技术文章
  2. Spring Integration application does not define channels when executed as packaged jar

Spring Integration application does not define channels when executed as packaged jar

由 别等时光非礼了梦想. 提交于 2019-12-05 19:33:58

My best guess is the shade plugin is having some effect on the order in which BeanPostProcessors are run.

Does the app work if you explicitly define the channel...

@Bean
public MessageChannel gatewayChannel() {
    return new DirectChannel();
}

...?

If so, that would be a smoking gun. In that case, the next step would be to get a DEBUG log for org.springframework in both environments and compare the bean definition/creation/post processing logs.

If you can post a complete (simple) example that exhibits the problem, we can take a look.

EDIT

The problem is the shade plugin does not merge the META-INF/spring.factories files, so we lose the entry from the JAVA DSL and hence don't process any IntegrationFlows...

From the Uber jar we just have the core file...

org.springframework.integration.config.IntegrationConfigurationInitializer=\
org.springframework.integration.config.GlobalChannelInterceptorInitializer,\
org.springframework.integration.config.IntegrationConverterInitializer,\
org.springframework.integration.config.IdempotentReceiverAutoProxyCreatorInitializer

and so are missing the additional initializer from the DSL jar...

org.springframework.integration.config.IntegrationConfigurationInitializer=\
org.springframework.integration.dsl.config.DslIntegrationConfigurationInitializer

Hence it works with 5.0.1 because the DSL is now part of core.

Spring Boot solves this problem by nesting the jars instead of extracting all the classes.

EDIT2

Here's another work-around, if you can't move to Spring Integration 5. Add this bean to your application...

@Bean
public static BeanFactoryPostProcessor dslInitializer() {
    return new BeanFactoryPostProcessor() {

        @Override
        public void postProcessBeanFactory(ConfigurableListableBeanFactory bf) throws BeansException {
            new DslIntegrationConfigurationInitializer().initialize(bf);
        }

    };
}

(Notice static).

Adding to Gary Russell's answer: The problem is indeed that the META-INF/spring.factories files are not automatically merged by the shade plugin.

You can use the AppendingTransformer of the shade plugin to merge these files.

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <executions>
        <execution>
            <goals>
                <goal>shade</goal>
            </goals>
            <configuration>
                <shadedArtifactAttached>true</shadedArtifactAttached>
                <transformers>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                        <mainClass>com.my.MainClass</mainClass>
                    </transformer>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                        <resource>META-INF/spring.handlers</resource>
                    </transformer>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                        <resource>META-INF/spring.schemas</resource>
                    </transformer>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                        <resource>META-INF/spring.tooling</resource>
                    </transformer>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
                        <resource>META-INF/spring.factories</resource>
                    </transformer>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer" />
                </transformers>
                <filters>
                    <filter>
                        <artifact>*:*</artifact>
                        <excludes>
                            <exclude>META-INF/*.SF</exclude>
                            <exclude>META-INF/*.DSA</exclude>
                            <exclude>META-INF/*.RSA</exclude>
                        </excludes>
                    </filter>
                </filters>
            </configuration>
        </execution>
    </executions>
</plugin>
标签
maven
spring-integration
易学教程内所有资源均来自网络或用户发布的内容，如有违反法律规定的内容欢迎反馈！
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!