spring load dynamically beans from xml which use property injection

Question

I need to load bean definitions from XML. The file is in a remote location (http) which is configured by properties. The properties should also be loaded from a remote location (a spring cloud config server)

constraints:

Spring 4.3.14 (not boot)
should be in runtime and after my properties already loaded
beans defined in xml are referencing properties in context
server URI (to fetch the xml from) should be in properties and not environment variable or profile depandant

The current setup I have works well when MY_XML_URI is passed as environment variable:

${SPRING_CONFIG_URI}/master/application-${spring.profiles.active}.properties

<import resource="${MY_XML_URI}/myBeans.xml"/>

And in the remote location, myBeans.xml with lots of beans e.g.

<bean name="mySpecialBean" class="com.example.MyGenericBean">
        <constructor-arg value="mySpecialBean"/>
        <constructor-arg value="${special.bean.config.expression}"/>
</bean>

However trouble starts when I want to get MY_XML_URI from the properties context, it doesn't resolve …

I have tried several approaches e.g:

java configuration class with @ImportResource({"${xml.server.uri}"}) but the properties are not loaded yet so it not converting to real value of xml.server.uri .
```
@Configuration
@ImportResource({"${xml.server.uri:http://localhost:8888}/myBeans.xml"})
public class MyConfiguration {}
```

expose dummy bean which fetch xml as resource and load the beans to parent applicationcontext - i must have it available to other beans dependant on those beans defined in xml. This solution was not injecting the properties context to my beans so failed to init them.

@Configuration
public class RiskConfig {

        @Value("${xml.server.uri}")
        private String xmlUri;

        @Autowired
        @Bean
        public Object myBean(ApplicationContext applicationContext) {
                Resource resource = applicationContext.getResource(xmlUri + "myBeans.xml");

//              not working since its not loading the beans to the main context
//              GenericApplicationContext genericApplicationContext = new GenericApplicationContext(applicationContext);
//              XmlBeanDefinitionReader reader = new XmlBeanDefinitionReader(genericApplicationContext);
//              reader.loadBeanDefinitions(resource);

                AutowireCapableBeanFactory factory = applicationContext.getAutowireCapableBeanFactory();
                BeanDefinitionRegistry registry = (BeanDefinitionRegistry) factory;

                XmlBeanDefinitionReader reader = new XmlBeanDefinitionReader(registry);
                reader.loadBeanDefinitions(resource);

                return new Object();
        }
}

Finally - is there a way to load the beans from xml programmatically to parent application context (which is already exist) though they are injected with properties.

placeholders in `import` elements are only resolved from the system properties or the environment. Not from loaded property files. Loading property files and contexts isn't a multi pass operation, so what you want isn't possible. At least not possible without coding something up yourself. — M. Deinum, Jul 19 '18 at 08:38
@m-deinum i don't mind coding something, do you have any specific suggestion or some spring hook to implement for this ? — Yoni, Jul 19 '18 at 19:32
Did you manage to make this work? If so, would you mind providing an Answer below so others can benefit? Thanks. — Jamie Bisotti, Mar 08 '22 at 17:30
@JamieBisotti couldn't find a way to do exactly as I wanted, programmatically or load the URI from the configuration. I kept the solution as written above where I set the remote URI, aka MY_XML_URI, as an environment variable. The deployment script prepares the env variables responsible to fetch the real value of MY_XML_URI from our configuration server. — Yoni, Mar 13 '22 at 09:17

spring load dynamically beans from xml which use property injection

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