How do you set cache headers in Spring MVC?

Question

In an annotation-based Spring MVC controller, what is the preferred way to set cache headers for a specific path?

Answer 1

I just encountered the same problem, and found a good solution already provided by the framework. The org.springframework.web.servlet.mvc.WebContentInterceptor class allows you to define default caching behaviour, plus path-specific overrides (with the same path-matcher behaviour used elsewhere). The steps for me were:

1. Ensure my instance of org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter does not have the "cacheSeconds" property set.

2. Add an instance of WebContentInterceptor:

   <mvc:interceptors>
   ...
   <bean class="org.springframework.web.servlet.mvc.WebContentInterceptor" p:cacheSeconds="0" p:alwaysUseFullPath="true" >
       <property name="cacheMappings">
           <props>
               <!-- cache for one month -->
               <prop key="/cache/me/**">2592000</prop>
               <!-- don't set cache headers -->
               <prop key="/cache/agnostic/**">-1</prop>
           </props>
       </property>
   </bean>
   ...
   </mvc:interceptors>
   

After these changes, responses under /foo included headers to discourage caching, responses under /cache/me included headers to encourage caching, and responses under /cache/agnostic included no cache-related headers.

---

If using a pure Java configuration:

@EnableWebMvc
@Configuration
public class WebMvcConfig extends WebMvcConfigurerAdapter {
  /* Time, in seconds, to have the browser cache static resources (one week). */
  private static final int BROWSER_CACHE_CONTROL = 604800;

  @Override
  public void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry
     .addResourceHandler("/images/**")
     .addResourceLocations("/images/")
     .setCachePeriod(BROWSER_CACHE_CONTROL);
  }
}

See also: http://docs.spring.io/spring-security/site/docs/current/reference/html/headers.html

Answer 2

The answer is quite simple:

@Controller
public class EmployeeController {

    @RequestMapping(value = "/find/employer/{employerId}", method = RequestMethod.GET)
    public List getEmployees(@PathVariable("employerId") Long employerId, final HttpServletResponse response) {
        response.setHeader("Cache-Control", "no-cache");
        return employeeService.findEmployeesForEmployer(employerId);
    }

}

Code above shows exactly what you want to achive. You have to do two things. Add "final HttpServletResponse response" as your parameter. And then set header Cache-Control to no-cache.

Answer 3

org.springframework.web.servlet.support.WebContentGenerator, which is the base class for all Spring controllers has quite a few methods dealing with cache headers:

/* Set whether to use the HTTP 1.1 cache-control header. Default is "true".
 * <p>Note: Cache headers will only get applied if caching is enabled
 * (or explicitly prevented) for the current request. */
public final void setUseCacheControlHeader();

/* Return whether the HTTP 1.1 cache-control header is used. */
public final boolean isUseCacheControlHeader();

/* Set whether to use the HTTP 1.1 cache-control header value "no-store"
 * when preventing caching. Default is "true". */
public final void setUseCacheControlNoStore(boolean useCacheControlNoStore);

/* Cache content for the given number of seconds. Default is -1,
 * indicating no generation of cache-related headers.
 * Only if this is set to 0 (no cache) or a positive value (cache for
 * this many seconds) will this class generate cache headers.
 * The headers can be overwritten by subclasses, before content is generated. */
public final void setCacheSeconds(int seconds);

They can either be invoked within your controller prior to content generation or specified as bean properties in Spring context.

Answer 4

Starting with Spring 4.2 you can do this:

import org.springframework.http.CacheControl;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import java.util.concurrent.TimeUnit;

@RestController
public class CachingController {
    @RequestMapping(method = RequestMethod.GET, path = "/cachedapi")
    public ResponseEntity<MyDto> getPermissions() {

        MyDto body = new MyDto();

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

CacheControl object is a builder with many configuration options, see JavaDoc

Answer 5

You could use a Handler Interceptor and use the postHandle method provided by it:

http://static.springsource.org/spring/docs/2.0.x/api/org/springframework/web/servlet/HandlerInterceptor.html

postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) 

then just add a header as follows in the method:

response.setHeader("Cache-Control", "no-cache");

Answer 6

I found WebContentInterceptor to be the easiest way to go.

@Override
public void addInterceptors(InterceptorRegistry registry)
{
    WebContentInterceptor interceptor = new WebContentInterceptor();
    interceptor.addCacheMapping(CacheControl.noCache(), "/users", "admin");
    registry.addInterceptor(interceptor);
}

Answer 7

you can define a anotation for this: @CacheControl(isPublic = true, maxAge = 300, sMaxAge = 300), then render this anotation to HTTP Header with Spring MVC interceptor. or do it dynamic:

int age = calculateLeftTiming();
String cacheControlValue = CacheControlHeader.newBuilder()
      .setCacheType(CacheType.PUBLIC)
      .setMaxAge(age)
      .setsMaxAge(age).build().stringValue();
if (StringUtils.isNotBlank(cacheControlValue)) {
    response.addHeader("Cache-Control", cacheControlValue);
}

Implication can be found here: 优雅的Builder模式

BTW: I just found that Spring MVC has build-in support for cache control: Google WebContentInterceptor or CacheControlHandlerInterceptor or CacheControl, you will find it.

Answer 8

I know this is a really old one, but those who are googling, this might help:

@Override
protected void addInterceptors(InterceptorRegistry registry) {

    WebContentInterceptor interceptor = new WebContentInterceptor();

    Properties mappings = new Properties();
    mappings.put("/", "2592000");
    mappings.put("/admin", "-1");
    interceptor.setCacheMappings(mappings);

    registry.addInterceptor(interceptor);
}

Answer 9

In your controller, you can set response headers directly.

response.setHeader("Cache-Control", "no-cache, no-store, must-revalidate");
response.setHeader("Pragma", "no-cache");
response.setDateHeader("Expires", 0);

Answer 10

You could extend AnnotationMethodHandlerAdapter to look for a custom cache control annotation and set the http headers accordingly.