How to configure i18n in Spring boot 2 + Webflux + Thymeleaf?

Question

I just start a new project based on Spring boot 2 + Webflux. On upgrading version of spring boot and replace spring-boot-starter-web with spring-boot-starter-

Answer 1

Another solution with spring boot starter web flux, which is much more cleaner, is to define your own HttpHandler using WebHttpHandlerBuilder in which you can set your LocaleContextResolver.

Documentation (see 1.2.2. WebHandler API) : https://docs.spring.io/spring/docs/current/spring-framework-reference/web-reactive.html#webflux-config-customize

MyLocaleContextResolver.java

public class MyLocaleContextResolver implements LocaleContextResolver {


    @Override
    public LocaleContext resolveLocaleContext(ServerWebExchange exchange) {      
        return new SimpleLocaleContext(Locale.FRENCH);        
    }

    @Override
    public void setLocaleContext(ServerWebExchange exchange, LocaleContext localeContext) {
        throw new UnsupportedOperationException();
    }
}

Then in a config file (annotated with @Configuration) or in your spring boot application file, defined your own HttpHandler bean.

Application.java

@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Bean
    public HttpHandler httpHandler(ApplicationContext context) {

        MyLocaleContextResolver localeContextResolver = new MyLocaleContextResolver();

        return WebHttpHandlerBuilder.applicationContext(context)
                .localeContextResolver(localeContextResolver) // set your own locale resolver
                .build();

    }

}

That's it!