Support property placeholders in url attribute of @HttpExchange

[jcthalys]

Affects: 6.0.4
Spring Boot: 3.0.1

@SpringBootApplication
public class DemoExchangeApplication {

	public static void main(String[] args) {
		SpringApplication.run(DemoExchangeApplication.class, args);
	}
	@Bean
	ApplicationListener<ApplicationReadyEvent> ready(GoogleClient googleClient) {
		return event -> {
			String googlePage = googleClient.getGooglePage();
			System.out.println(googlePage);
		};
	}
	@Bean
	GoogleClient googleClient(HttpServiceProxyFactory factory) {
		return factory.createClient(GoogleClient.class);
	}
	@Bean
	HttpServiceProxyFactory getHttpServiceProxyFactory(WebClient.Builder builder) {
		return HttpServiceProxyFactory.builder()
				.clientAdapter(WebClientAdapter.forClient(builder.build())).build();
	}
}

@HttpExchange(url = "${google.url}")
interface GoogleClient {
	@GetExchange
	String getGooglePage();
}

If I have the url = "www.google.com" directly it work just fine, but using the property placeholder it's not getting resolved from the application.properties or yml..

java.lang.IllegalArgumentException: Map has no value for 'google.url'
	at org.springframework.web.util.UriComponents$MapTemplateVariables.getValue(UriComponents.java:348) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.util.UriComponents.expandUriComponent(UriComponents.java:263) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.util.HierarchicalUriComponents$FullPathComponent.expand(HierarchicalUriComponents.java:921) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.util.HierarchicalUriComponents.expandInternal(HierarchicalUriComponents.java:439) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.util.HierarchicalUriComponents.expandInternal(HierarchicalUriComponents.java:52) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.util.UriComponents.expand(UriComponents.java:161) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.util.DefaultUriBuilderFactory$DefaultUriBuilder.build(DefaultUriBuilderFactory.java:391) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.util.DefaultUriBuilderFactory.expand(DefaultUriBuilderFactory.java:149) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.reactive.function.client.DefaultWebClient$DefaultRequestBodyUriSpec.uri(DefaultWebClient.java:228) ~[spring-webflux-6.0.4.jar:6.0.4]
	at org.springframework.web.reactive.function.client.DefaultWebClient$DefaultRequestBodyUriSpec.uri(DefaultWebClient.java:189) ~[spring-webflux-6.0.4.jar:6.0.4]
	at org.springframework.web.reactive.function.client.support.WebClientAdapter.newRequest(WebClientAdapter.java:105) ~[spring-webflux-6.0.4.jar:6.0.4]
	at org.springframework.web.reactive.function.client.support.WebClientAdapter.requestToBody(WebClientAdapter.java:69) ~[spring-webflux-6.0.4.jar:6.0.4]
	at org.springframework.web.service.invoker.HttpServiceMethod$ResponseFunction.lambda$initBodyFunction$5(HttpServiceMethod.java:378) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.service.invoker.HttpServiceMethod$ResponseFunction.execute(HttpServiceMethod.java:288) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.service.invoker.HttpServiceMethod.invoke(HttpServiceMethod.java:105) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.web.service.invoker.HttpServiceProxyFactory$HttpServiceMethodInterceptor.invoke(HttpServiceProxyFactory.java:271) ~[spring-web-6.0.4.jar:6.0.4]
	at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:184) ~[spring-aop-6.0.4.jar:6.0.4]
	at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:218) ~[spring-aop-6.0.4.jar:6.0.4]
	at com.example.demoexchange.$Proxy49.getGooglePage(Unknown Source) ~[na:na]
	at com.example.demoexchange.DemoExchangeApplication.lambda$ready$0(DemoExchangeApplication.java:24) ~[main/:na]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176) ~[spring-context-6.0.4.jar:6.0.4]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169) ~[spring-context-6.0.4.jar:6.0.4]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143) ~[spring-context-6.0.4.jar:6.0.4]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:413) ~[spring-context-6.0.4.jar:6.0.4]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:370) ~[spring-context-6.0.4.jar:6.0.4]
	at org.springframework.boot.context.event.EventPublishingRunListener.ready(EventPublishingRunListener.java:109) ~[spring-boot-3.0.1.jar:3.0.1]
	at org.springframework.boot.SpringApplicationRunListeners.lambda$ready$6(SpringApplicationRunListeners.java:80) ~[spring-boot-3.0.1.jar:3.0.1]
	at java.base/java.lang.Iterable.forEach(Iterable.java:75) ~[na:na]
	at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:118) ~[spring-boot-3.0.1.jar:3.0.1]
	at org.springframework.boot.SpringApplicationRunListeners.doWithListeners(SpringApplicationRunListeners.java:112) ~[spring-boot-3.0.1.jar:3.0.1]
	at org.springframework.boot.SpringApplicationRunListeners.ready(SpringApplicationRunListeners.java:80) ~[spring-boot-3.0.1.jar:3.0.1]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) ~[spring-boot-3.0.1.jar:3.0.1]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1302) ~[spring-boot-3.0.1.jar:3.0.1]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1291) ~[spring-boot-3.0.1.jar:3.0.1]
	at com.example.demoexchange.DemoExchangeApplication.main(DemoExchangeApplication.java:18) ~[main/:na]

[DanielLiu1123]

You can pass a StringValueResolver to support this feature.

@Bean
HttpServiceProxyFactory getHttpServiceProxyFactory(WebClient.Builder builder, Environment env) {
    return HttpServiceProxyFactory.builder()
                .embeddedValueResolver(env::resolvePlaceholders)
	        .clientAdapter(WebClientAdapter.forClient(builder.build())).build();
}

[rstoyanchev]

@DanielLiu1123 is correct. You need to give the resolver for placeholders to HttpServiceProxyFactory. When spring-projects/spring-boot#31337 is resolved, you should be able to inject a pre-configured HttpServiceProxyFactory.Builder and this will become more convenient.