Spring single page for every url route and subrout

Question

I'm building spring website that has react single page app under subroute and my current url structure should look like

localhost/admin/** => react app
localhost/**       => spring thymeleaf/rest/websocket app for everything else

react app mapping:
localhost/admin/static/**  => static react files
localhost/admin/**         => react index.html for everything else

Example of project resources structure:  
resources/
    admin/         <= my admin react files is here
        index.html
        static/    <= react css, js,  statics
    templates/     <= thymeleaf templates
    static/        <= theamleaf static
    ...

So i need to forward react index.html file for every url route and its subroutes. Basically single page app for everything except static files

Looks like a common task, and here is some things i have already tried:

---

Full working demo of project spring + react + how gradle builds project and why i can't put react files in different directory (/resources/static for example): https://github.com/varren/spring-react-example

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Can't use forward:/admin/index.html for /admin/** because this will create recursion because admin/index.html is also under admin/** and have to intercept admin/static/** somehow.

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Can't use addResourceHandlers in WebMvcConfigurerAdapter

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/admin/**")
            .addResourceLocations("classpath:/admin/");
}

index.html mapped only to /admin/index.html url, and this option almost works but only if you access the react app from localhost/admin/index.html

---

Saw this and this and this and many other links and i also have kinda solution, but maybe there is generic option i just can't see

Answer 1

Right now i'm using custom ResourceResolver to solve this

Demo: https://github.com/varren/spring-react-example

@Configuration
public class BaseWebMvcConfigurerAdapter extends WebMvcConfigurerAdapter {
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {

        ResourceResolver resolver = new AdminResourceResolver();
        registry.addResourceHandler("/admin/**")
                .resourceChain(false)
                .addResolver(resolver);


        registry.addResourceHandler("/admin/")
                .resourceChain(false)
                .addResolver(resolver);
    }


    private class AdminResourceResolver implements ResourceResolver {
        private Resource index = new ClassPathResource("/admin/index.html");

        @Override
        public Resource resolveResource(HttpServletRequest request, String requestPath, List<? extends Resource> locations, ResourceResolverChain chain) {
            return resolve(requestPath, locations);
        }

        @Override
        public String resolveUrlPath(String resourcePath, List<? extends Resource> locations, ResourceResolverChain chain) {
            Resource resolvedResource = resolve(resourcePath, locations);
            if (resolvedResource == null) {
                return null;
            }
            try {
                return resolvedResource.getURL().toString();
            } catch (IOException e) {
                return resolvedResource.getFilename();
            }
        }

        private Resource resolve(String requestPath, List<? extends Resource> locations) {

            if(requestPath == null) return null;

            if (!requestPath.startsWith("static")) {
                return index;
            }else{
                return new ClassPathResource("/admin/" + requestPath);
            }
        }
    }
}