SpringBoot Rest application on App engine gives EofException error when going through a Filter

[gaurav bhandari]

The below error occurs if a Filter class is implemented. If the filter class is removed, the api works properly.

Error Message-

 

Code-

Startup -

@ServletComponentScan
@SpringBootApplication
public class RestBoot {
    public static void main(String[] args) {
        SpringApplication.run(RestBoot.class, args);
    }
}

Filter -

@WebFilter(urlPatterns = "/*")
@Configuration
public class AuthFilter implements Filter {

    @Autowired
    DataSource pool;

    @Override
    public void doFilter(ServletRequest req, ServletResponse servletResponse, FilterChain chain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        if (!request.isSecure()) {
            response.sendError(HttpServletResponse.SC_FORBIDDEN, "Insecure Request.");
        }

        if( request.getRequestURI().contains("trial")) {
                chain.doFilter(request , response );
                System.out.println("Done");
            }

      }

Controller -

@RestController
public class RestApiController {

    @Autowired
    private DataSource pool;

    @GetMapping("/trial")
    public ResponseEntity<String> hello() {

        String abc1 = hello;
        return new ResponseEntity<String>(abc1, HttpStatus.OK);
        //return "Hello world! " + abc1;
    }

}

Please advice what could be causing the issue.