How to cache ResponseEntity<Resource> in spring boot

Question

I am trying to cache ResponseEntity in spring boot but unable to find a proper way to implement the same.

There are few examples where

        return ResponseEntity.ok()
            .cacheControl(CacheControl.maxAge(20, TimeUnit.SECONDS))
            .body(body);

But my problem here is that I am using an external library that returns

ResponseEntity<Resource>

and I wanted to cache that response. so it should be like

ResponseEntity<Resource> getResource() {
     
       ResponseEntity<Resource> resource = getResourceFromExternalFunction();
       // wanted to cache this resource
       return cachedResource
}

If I apply above technique for my code, it would be like

ResponseEntity<Resource> getResource() {
     
       ResponseEntity<Resource> resource = getResourceFromExternalFunction();
       return ResponseEntity.ok()
            .cacheControl(CacheControl.maxAge(20, TimeUnit.SECONDS))
            .body(resource );
}

it would return

ResourceEntity<ResourceEntity<Resource>> 

which is not expected. Can some one help here please

Answer 1

Always be on the look out for SpringBoot libraries that already exist before you try and reinvent the wheel. Lucky for you, the Spring community already has such a caching library which should make your life much easier, you can find a tutorial on it here:

Baeldung: A Guide to Caching in Spring