REST API custom exception handling

Hi Cuba Team,

I used a POST request to http://localhost:8080/app/rest/v2/entities/Project$Entity to insert a record in a Postgresql table. On this table, I have a trigger that validates data and raises a PSQL Exception if some specific data is inserted. I want to expose this error message to the client (as it is), because now I get only:


{
    "error": "Server error",
    "details": ""
}

What is the best approach to achieve this?
(I saw the method that returns the above message is: handleException of the class: com.haulmont.restapi.controllers.RestControllerExceptionHandler)

Thanks.

1 Like

Hi,
you can create your own exception handler that will override the standard behavior. Something like this:


@ControllerAdvice("com.haulmont.restapi.controllers")
@Order(Ordered.HIGHEST_PRECEDENCE)
public class MyRestControllerExceptionHandler {

    private Logger log = LoggerFactory.getLogger(MyRestControllerExceptionHandler.class);

    @ExceptionHandler(Exception.class)
    @ResponseBody
    public ResponseEntity<ErrorInfo> handleException(Exception e) {
        log.error("Exception in REST controller", e);
        ErrorInfo errorInfo = new ErrorInfo("Server error", e.getMessage());
        return new ResponseEntity<>(errorInfo, HttpStatus.INTERNAL_SERVER_ERROR);
    }
}

This ControllerAdvice has higher priority than a standard one, so it will handle your exceptions.

Also you will need to add a package with your own controller advice to the spring component-scan. You’ll have to create a rest-dispatcher-spring.xml file in the main directory of your web module (e.g. com.company.myproject). The file should look like this:


<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:security="http://www.springframework.org/schema/security"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security-4.2.xsd">

    <!-- Define a base package for your controllers-->
    <context:component-scan base-package="com.company.myproject.rest"/>

</beans>

Your exception handler class must be under the com.company.myproject.rest directory.

Then register the rest-disptacher-spring.xml file in the web-app.properties:


cuba.restSpringContextConfig = +com/company/myproject/rest-dispatcher-spring.xml

Thank you

Hello, I have implemented the class as suggested, and it works. The problem I have is that now pertinent
logging is not shown neither in the File nor the Console appender. Any ideas ?