I had the same concern and was not a fan of the Spring EL option due to the issues documented and I wanted the prefix to be tightly controlled in the controllers but I did not want to depend on the developers doing the right thing.
There might be a better way these days but this is what I did. Can you guys see any downsides, I am still in the process of testing any side-effects.
- Define a custom annotation.
This allows a developer to explicitly provide typed attributes such as int apiVersion(), String resourceName(). These values would be the basis of the prefix later.
- Annotated rest controllers with this new annotation
- Implemented a custom RequestMappingHandlerMapping
In the RequestMappingHandlerMapping, I could read the attribute of the custom annotation and modify the final RequestMappingInfo as I needed. Here are a few code snippets:
@Configuration
public class MyWebMvcConfigurationSupport extends WebMvcConfigurationSupport {
@Bean
public RequestMappingHandlerMapping requestMappingHandlerMapping() {
return new MyCustomRequestMappingHandlerMapping();
}
}
And in the MyCustomRequestMappingHandlerMapping, overwrite the registerHandlerMethod:
private class MyCustomRequestMappingHandlerMapping extends RequestMappingHandlerMapping {
private Logger myLogger = LoggerFactory.getLogger(MyCustomRequestMappingHandlerMapping.class);
public MyCustomRequestMappingHandlerMapping() {
super();
}
@Override
protected void registerHandlerMethod(Object handler, Method method, RequestMappingInfo mapping) {
// find the class declaring this method
Class<?> beanType = method.getDeclaringClass();
// check for the My rest controller annotation
MyRestController myRestAnnotation = beanType.getAnnotation(MyRestController.class);
if (myRestAnnotation != null) {
// this is a My annotated rest service, lets modify the URL mapping
PatternsRequestCondition oldPattern = mapping.getPatternsCondition();
// create a pattern such as /api/v${apiVersion}/${resourceName}
String urlPattern = String.format("/api/v%d/%s",
myRestAnnotation.apiVersion(),
myRestAnnotation.resourceName());
// create a new condition
PatternsRequestCondition apiPattern =
new PatternsRequestCondition(urlPattern);
// ask our condition to be the core, but import all settinsg from the old
// pattern
PatternsRequestCondition updatedFinalPattern = apiPattern.combine(oldPattern);
myLogger.info("re-writing mapping for {}, myRestAnnotation={}, original={}, final={}",
beanType, myRestAnnotation, oldPattern, updatedFinalPattern);
mapping = new RequestMappingInfo(
mapping.getName(),
updatedFinalPattern,
mapping.getMethodsCondition(),
mapping.getParamsCondition(),
mapping.getHeadersCondition(),
mapping.getConsumesCondition(),
mapping.getProducesCondition(),
mapping.getCustomCondition()
);
}
super.registerHandlerMethod(handler, method, mapping);
}
}