Spring Swagger 2 not working when i have a custom HandlerInterceptorAdapter - spring-boot

Question

Im using a spring boot 1.5.3 along side swagger 2.7.0 (can't upgrade because higher versions dont work on IE)
i got everything to work fine but when i add a custom HandlerInterceptorAdapter its not working giving me this error:
Cannot read property 'validatorUrl' of null springfox.js: 72
here is my swagger config
#Configuration
#EnableSwagger2
public class SwaggerConfig {
public Docket api() {
Docket docket = new Docket(DocumentationType.SWAGGER_2).select()
.apis(RequestHandlerSelectors
.basePackage("net.guides.springboot2.springboot2swagger2.controller"))
.paths(PathSelectors.regex("/.*"))
.build().apiInfo(apiEndPointsInfo());
docket.ignoredParameterTypes(HttpServletResponse.class, HttpServletRequest.class); // this didnt help
return docket;
}
private ApiInfo apiEndPointsInfo() {
return new ApiInfoBuilder().title("SWAT Rest API")
.description("SWAT Rest API documentation")
.contact(new Contact("xxx", "xxxx", "xxxxx"))
.license("Apache 2.0")
.licenseUrl("http://www.apache.org/licenses/LICENSE-2.0.html")
.version("5.2.2")
.build();
}
}
and here is the config that gives me a hard time
#Configuration
#Slf4j
public class SwatStaticResourceConfig extends WebMvcConfigurerAdapter {
#Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
log.debug("Adding static folders to serve images");
// registry.addResourceHandler("/images/**").addResourceLocations("file:./images/");
//registry.addResourceHandler("/docs/**").addResourceLocations("file:./docs/");
registry.addResourceHandler("/images/**", "/docs/**").addResourceLocations("file:./images/", "file:./docs/");
}
#Override
public void addInterceptors(InterceptorRegistry registry) {
registry.addInterceptor(new SwatRequestInterceptor()); // if i disable this line than swagger is working fine
super.addInterceptors(registry);
}
}
in case its needed here is the interceptor class
#Slf4j
public class SwatRequestInterceptor extends HandlerInterceptorAdapter {
#Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
Principal user = request.getUserPrincipal();
if (user == null) {
log.error("No user for request: " + request.getRequestURL().toString());
return false;
} else {
log.debug("Got the following request: " + request.getMethod().toUpperCase() + " " + request.getRequestURL().toString() + ", FROM: " + user.getName());
return true;
}
}
#Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
ModelAndView modelAndView) throws Exception {
Principal user = request.getUserPrincipal();
log.debug("Completed the following request: " + request.getMethod().toUpperCase() + " " + request.getRequestURL().toString() + ", FROM: " + user.getName());
super.postHandle(request, response, handler, modelAndView);
}
}

Answer 1

I was getting same issue but Resolved it by making sure that WebMvcConfigurationSupport is extended only by a single class preferably where you are registering your interceptor.
Also, make sure to add the following for swagger config class:
#Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
registry.addResourceHandler("swagger-ui.html").addResourceLocations("classpath:/META-INF/resources/");
registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
}