Spring Boot - Database based request mapping - spring

Question

Using Spring Boot 2 I want to create a database based request mapping. I mean, instead of using hundreds of #RequestMapping annotations on the controllers I would like to store the mapping in a database table.
Each of the controllers implements an interface that has an execute method so I simply search for the relevant controller in the DB and call the execute method on it.
At the moment I have a CustomController with a #RequestMapping("*") and this controller finds the real controller and calls the execute method. It works but it is not a good solution. For example at interceptor level the handler object is the CustomController and not the real controller.
Probably I should use the SimpleUrlHandlerMapping like this:
#Bean
public SimpleUrlHandlerMapping simpleUrlHandlerMapping() {
SimpleUrlHandlerMapping simpleUrlHandlerMapping = new SimpleUrlHandlerMapping();
Map<String, Object> urlMap = new HashMap<>();
urlMap.put("/dashboard", __???__);
simpleUrlHandlerMapping.setUrlMap(urlMap);
return simpleUrlHandlerMapping;
}
But in this case I don't know how to fill the bean value in the urlMap. For example in case of "/dashboard" how to put the DashboardController.execute().
Maybe any better solution?
UPDATE 1
I have created a SimpleUrlHandlerMapping like this:
#Configuration
public class SimpleUrlHandlerMappingConfig {
#Autowired
private ApplicationContext context;
#Bean
public SimpleUrlHandlerMapping simpleUrlHandlerMapping() {
SimpleUrlHandlerMapping simpleUrlHandlerMapping = new SimpleUrlHandlerMapping();
Map<String, Object> urlMap = new HashMap<>();
String path = "/dashboard";
String controllerName = "dashboardController";
Object myController = context.getBean(controllerName);
urlMap.put(path, myController);
simpleUrlHandlerMapping.setUrlMap(urlMap);
return simpleUrlHandlerMapping;
}
}
And a CustomHandlerAdapter as:
#Configuration
public class CustomHandlerAdapter implements HandlerAdapter {
protected final Logger logger = LoggerFactory.getLogger(this.getClass());
#Override
public boolean supports(Object handler) {
logger.debug("Test handler: " + handler);
if (handler instanceof PageController) {
return true;
}
return false;
}
#Override
public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
logger.debug("Custom handle");
ModelAndView mv = new ModelAndView();
String viewName = ((PageController)handler).execute2(request, response);
mv.setViewName(viewName);
return mv;
}
#Override
public long getLastModified(HttpServletRequest request, Object handler) {
return -1;
}
}
But according to logs it seems that SimpleUrlHandlerMapping doesn't work correctly:
- DispatcherServlet with name 'dispatcherServlet' processing GET request for [/dashboard]
- Looking up handler method for path /dashboard
- Did not find handler method for [/dashboard]
- Matching patterns for request [/dashboard] are [/**]
- URI Template variables for request [/dashboard] are {}
- Mapping [/dashboard] to HandlerExecutionChain with handler [ResourceHttpRequestHandler [locations=[class path resource [META-INF/resources/], class path resource [resources/], class path resource [static/], class path resource [public/], ServletContext resource [/]], resolvers=[org.springframework.web.servlet.resource.PathResourceResolver#4bc6044e]]] and 1 interceptor
- Test handler: ResourceHttpRequestHandler [locations=[class path resource [META-INF/resources/], class path resource [resources/], class path resource [static/], class path resource [public/], ServletContext resource [/]], resolvers=[org.springframework.web.servlet.resource.PathResourceResolver#4bc6044e]]
- Last-Modified value for [/dashboard] is: -1
UPDATE 2
Thanks to #M. Deinum I have updated my code and have a working solution.
Please note that #EnableWebMvc was introduced and that can cause other side effects later.
The SimpleUrlHandlerMappingConfig:
#Configuration()
#Order(Ordered.HIGHEST_PRECEDENCE)
public class SimpleUrlHandlerMappingConfig {
#Autowired
private ApplicationContext context;
#Bean
#Order(Ordered.HIGHEST_PRECEDENCE)
public SimpleUrlHandlerMapping simpleUrlHandlerMapping() {
SimpleUrlHandlerMapping simpleUrlHandlerMapping = new SimpleUrlHandlerMapping();
Map<String, Object> urlMap = new HashMap<>();
String path = "/dashboard";
String controllerName = "dashboardController";
Object myController = context.getBean(controllerName);
urlMap.put(path, myController);
simpleUrlHandlerMapping.setUrlMap(urlMap);
return simpleUrlHandlerMapping;
}
}
The CustomHandlerAdapter:
#Component
public class CustomHandlerAdapter implements HandlerAdapter {
#Override
public boolean supports(Object handler) {
if (handler instanceof PageController) {
return true;
}
return false;
}
#Override
public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
ModelAndView mv = new ModelAndView();
String viewName = ((PageController)handler).execute2(request, response);
mv.setViewName(viewName);
return mv;
}
#Override
public long getLastModified(HttpServletRequest request, Object handler) {
return -1;
}
}
And the WebConfig:
#Configuration
#EnableWebMvc
public class WebConfig implements WebMvcConfigurer {
#Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
registry.addResourceHandler("/style/**")
.addResourceLocations("classpath:" + "/static/style/");
registry.addResourceHandler("/js/**")
.addResourceLocations("classpath:" + "/static/js/");
}
}

Answer 1

If I understood correctly, you want to get rid of the simple actions (get/post/put/delete) -- and those only call the save/find/delete methods from the repository.
If that is the case I suggest using Spring Data REST

Answer 2

I post the final solution (thanks to M. Deinum) here maybe helping somebody else.
So I only created a HandlerMapping using the SimpleUrlHandlerMapping:
#Configuration()
public class SimpleUrlHandlerMappingConfig {
#Autowired
private ApplicationContext context;
#Bean
public SimpleUrlHandlerMapping simpleUrlHandlerMapping() {
SimpleUrlHandlerMapping simpleUrlHandlerMapping = new SimpleUrlHandlerMapping();
Map<String, Object> urlMap = new HashMap<>();
String path = "/dashboard";
String controllerName = "dashboardController";
Object myController = context.getBean(controllerName);
urlMap.put(path, myController);
simpleUrlHandlerMapping.setUrlMap(urlMap);
simpleUrlHandlerMapping.setOrder(Ordered.HIGHEST_PRECEDENCE);
return simpleUrlHandlerMapping;
}
}
And a custom HandlerAdapter:
#Component
public class CustomHandlerAdapter implements HandlerAdapter {
#Override
public boolean supports(Object handler) {
if (handler instanceof PageController) {
return true;
}
return false;
}
#Override
public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
ModelAndView mv = new ModelAndView();
String viewName = ((PageController)handler).execute2(request, response);
mv.setViewName(viewName);
return mv;
}
#Override
public long getLastModified(HttpServletRequest request, Object handler) {
return -1;
}
}
Please note that this example demonstrates only the concept without proper error handling and real DB access.