| /* |
| * Copyright 2017 The Mifos Initiative. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package io.mifos.core.api.util; |
| |
| import feign.Feign; |
| import feign.FeignException; |
| import feign.Response; |
| import feign.Util; |
| import feign.codec.ErrorDecoder; |
| import io.mifos.core.api.annotation.ThrowsException; |
| import io.mifos.core.api.annotation.ThrowsExceptions; |
| import org.slf4j.Logger; |
| import org.springframework.http.HttpStatus; |
| |
| import java.io.IOException; |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.util.Arrays; |
| import java.util.Optional; |
| |
| /** |
| * @author Myrle Krantz |
| */ |
| class AnnotatedErrorDecoder implements ErrorDecoder { |
| |
| private final Class feignClientClass; |
| private final Logger logger; |
| |
| AnnotatedErrorDecoder(final Logger logger, final Class feignClientClass) { |
| this.logger = logger; |
| this.feignClientClass = feignClientClass; |
| } |
| |
| @Override |
| public Exception decode( |
| final String methodKey, |
| final Response response) { |
| final Optional<Optional<Optional<Exception>>> ret = |
| Arrays.stream(feignClientClass.getMethods()) |
| .filter(method -> Feign.configKey(feignClientClass, method).equals(methodKey)) |
| .map(method -> { |
| final Optional<ThrowsException> annotation = getMatchingAnnotation(response, method); |
| return annotation.map(a -> constructException(response, a)); |
| }) |
| .findAny(); |
| |
| return unwrapEmbeddedOptional(ret, getAlternative(methodKey, response)); |
| } |
| |
| private RuntimeException getAlternative(final String methodKey, final Response response) { |
| try { |
| final String bodyText = Util.toString(response.body().asReader()); |
| |
| if (response.status() == HttpStatus.BAD_REQUEST.value()) { |
| return new IllegalArgumentException(bodyText); |
| } else if (response.status() == HttpStatus.FORBIDDEN.value()) { |
| return new InvalidTokenException(bodyText); |
| } else if (response.status() == HttpStatus.NOT_FOUND.value()) { |
| return new NotFoundException(bodyText); |
| } else if (response.status() == HttpStatus.INTERNAL_SERVER_ERROR.value()) { |
| return new InternalServerError(bodyText); |
| } else { |
| return FeignException.errorStatus(methodKey, response); |
| } |
| |
| } catch (IOException e) { |
| |
| return FeignException.errorStatus(methodKey, response); |
| |
| } |
| } |
| |
| private Optional<ThrowsException> getMatchingAnnotation( |
| final Response response, |
| final Method method) { |
| |
| final ThrowsExceptions throwsExceptionsAnnotation = |
| method.getAnnotation(ThrowsExceptions.class); |
| if (throwsExceptionsAnnotation == null) { |
| final ThrowsException throwsExceptionAnnotation = |
| method.getAnnotation(ThrowsException.class); |
| if ((throwsExceptionAnnotation != null) && |
| statusMatches(response, throwsExceptionAnnotation)) { |
| return Optional.of(throwsExceptionAnnotation); |
| } |
| } else { |
| return Arrays.stream(throwsExceptionsAnnotation.value()) |
| .filter(throwsExceptionAnnotation -> statusMatches(response, |
| throwsExceptionAnnotation)) |
| .findAny(); |
| } |
| |
| return Optional.empty(); |
| } |
| |
| private boolean statusMatches(final Response response, |
| final ThrowsException throwsExceptionAnnotation) { |
| return throwsExceptionAnnotation.status().value() == response.status(); |
| } |
| |
| @SuppressWarnings("OptionalUsedAsFieldOrParameterType") |
| private <T> T unwrapEmbeddedOptional( |
| final Optional<Optional<Optional<T>>> embeddedOptional, T alternative) { |
| return embeddedOptional.orElse(Optional.empty()).orElse(Optional.empty()).orElse(alternative); |
| } |
| |
| private Optional<Exception> constructException( |
| final Response response, |
| final ThrowsException throwsExceptionAnnotations) { |
| try { |
| try { |
| final Constructor<? extends RuntimeException> oneArgumentConstructor = |
| throwsExceptionAnnotations.exception().getConstructor(Response.class); |
| |
| return Optional.of(oneArgumentConstructor.newInstance(response)); |
| } catch (final NoSuchMethodException e) { |
| |
| final Constructor<? extends RuntimeException> noArgumentConstructor = |
| throwsExceptionAnnotations.exception().getConstructor(); |
| |
| return Optional.of(noArgumentConstructor.newInstance()); |
| } |
| } catch (final InvocationTargetException |
| | IllegalAccessException |
| | InstantiationException |
| | NoSuchMethodException e) { |
| logger.error("Instantiating exception {}, in for status {} failed with an exception", |
| throwsExceptionAnnotations.exception(), throwsExceptionAnnotations.status(), e); |
| |
| return Optional.empty(); |
| } |
| } |
| } |