malinink / easy-tests

import com.atlassian.oai.validator.model.Request;

import com.atlassian.oai.validator.model.Response;

import com.atlassian.oai.validator.report.ValidationReport;

import java.io.IOException;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.springframework.core.io.support.EncodedResource;

import org.springframework.lang.Nullable;

import org.springframework.web.servlet.ModelAndView;

import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

import org.springframework.web.util.ContentCachingResponseWrapper;

/**

 * @author atlassian

 * An Interceptor which validates incoming requests against the defined swagger interface.

 */

@SuppressWarnings("checkstyle:MultipleStringLiterals")

public class SwaggerValidationInterceptor extends HandlerInterceptorAdapter {

    private static final Logger LOG = LoggerFactory.getLogger(SwaggerValidationInterceptor.class);

    private final SwaggerRequestValidationService swaggerRequestValidationService;

    public SwaggerValidationInterceptor(final EncodedResource swaggerInterface) throws IOException {

        this(new SwaggerRequestValidationService(swaggerInterface));

    }

    SwaggerValidationInterceptor(final SwaggerRequestValidationService swaggerRequestValidationService) {

        this.swaggerRequestValidationService = swaggerRequestValidationService;

    }

    /**

     * Validates the given requests. If a request is defined but invalid against the Swagger schema

     * an {@link InvalidRequestException} will be thrown leading to an error response.

     * <p>

     * Only {@link ResettableRequestServletWrapper} can be validated. Wrapping is done within the

     * {@link SwaggerValidationFilter}.

     *

     * @param servletRequest  the {@link HttpServletRequest} to validate

     * @param servletResponse the servlet response

     * @param handler         a handler

     * @return {@code true} if the request is valid against or not defined in the Swagger schema or

     * the servlet is not a {@link ResettableRequestServletWrapper}

     * @throws Exception if the request is invalid against the Swagger schema or the requests body

     *                   can't be read

     */

    @Override

    public boolean preHandle(

            final HttpServletRequest servletRequest,

            final HttpServletResponse servletResponse,

            final Object handler) throws Exception {

        // only wrapped servlet requests can be validated - see: SwaggerValidationFilter

        if (!(servletRequest instanceof ResettableRequestServletWrapper)) {

            return true;

        }

        // validate the request

        final ResettableRequestServletWrapper resettableRequest = (ResettableRequestServletWrapper) servletRequest;

        final String requestLoggingKey = servletRequest.getMethod() + "#" + servletRequest.getRequestURI();

        LOG.debug("Swagger request validation: {}", requestLoggingKey);

        final Request request = swaggerRequestValidationService.buildRequest(resettableRequest);

        final ValidationReport validationReport = swaggerRequestValidationService.validateRequest(request);

        if (!validationReport.hasErrors()) {

            LOG.debug("Swagger validation: {} - The request is valid.", requestLoggingKey);

        } else if (!swaggerRequestValidationService.isDefinedSwaggerRequest(validationReport)) {

            LOG.info("Swagger validation: {} - The request is not defined in the Swagger schema. Ignoring it.",

                    requestLoggingKey);

        } else {

            final InvalidRequestException invalidRequestException = new InvalidRequestException(validationReport);

            LOG.info("Swagger validation: {} - The REST request is invalid: {}", requestLoggingKey,

                    invalidRequestException.getMessage());

            throw invalidRequestException;

        }

        // reset the requests servlet input stream after reading it on former step

        resettableRequest.resetInputStream();

        return true;

    }

    }

}