2 * Copyright © 2019 FRINX s.r.o. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.restconf.nb.rfc8040.jersey.providers.errors;
10 import static java.util.Objects.requireNonNull;
11 import static org.opendaylight.yang.svc.v1.urn.ietf.params.xml.ns.yang.ietf.restconf.rev170126.YangModuleInfoImpl.qnameOf;
13 import com.google.common.annotations.VisibleForTesting;
14 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
15 import java.io.ByteArrayOutputStream;
16 import java.io.IOException;
17 import java.io.OutputStreamWriter;
18 import java.io.StringReader;
19 import java.io.StringWriter;
20 import java.nio.charset.StandardCharsets;
21 import java.util.Collections;
22 import java.util.LinkedHashSet;
23 import java.util.List;
24 import java.util.Optional;
26 import java.util.stream.Collectors;
27 import javax.ws.rs.core.Context;
28 import javax.ws.rs.core.HttpHeaders;
29 import javax.ws.rs.core.MediaType;
30 import javax.ws.rs.core.Response;
31 import javax.ws.rs.ext.ExceptionMapper;
32 import javax.ws.rs.ext.Provider;
33 import javax.xml.stream.XMLOutputFactory;
34 import javax.xml.stream.XMLStreamException;
35 import javax.xml.transform.OutputKeys;
36 import javax.xml.transform.TransformerException;
37 import javax.xml.transform.TransformerFactory;
38 import javax.xml.transform.stream.StreamResult;
39 import javax.xml.transform.stream.StreamSource;
40 import org.opendaylight.restconf.api.HttpStatusCode;
41 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
42 import org.opendaylight.restconf.nb.jaxrs.JaxRsMediaTypes;
43 import org.opendaylight.restconf.nb.rfc8040.ErrorTagMapping;
44 import org.opendaylight.restconf.server.api.DatabindContext;
45 import org.opendaylight.restconf.server.spi.DatabindProvider;
46 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.restconf.rev170126.errors.Errors;
47 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.restconf.rev170126.errors.errors.Error;
48 import org.opendaylight.yangtools.yang.common.QName;
49 import org.opendaylight.yangtools.yang.data.codec.gson.JsonWriterFactory;
50 import org.slf4j.Logger;
51 import org.slf4j.LoggerFactory;
54 * An {@link ExceptionMapper} that is responsible for transformation of thrown {@link RestconfDocumentedException} to
55 * {@code errors} structure that is modelled by RESTCONF module (see section 8 of RFC-8040).
59 // FIXME: NETCONF-1188: eliminate the need for this class by having a separate exception which a has a HTTP status and
60 // optionally holds an ErrorsBody -- i.e. the equivalent of Errors, perhaps as NormalizedNode,
61 // with sufficient context to send it to JSON or XML -- very similar to a NormalizedNodePayload
64 public final class RestconfDocumentedExceptionMapper implements ExceptionMapper<RestconfDocumentedException> {
65 private static final Logger LOG = LoggerFactory.getLogger(RestconfDocumentedExceptionMapper.class);
66 private static final MediaType DEFAULT_MEDIA_TYPE = MediaType.APPLICATION_JSON_TYPE;
67 private static final QName ERROR_TYPE_QNAME = qnameOf("error-type");
68 private static final QName ERROR_TAG_QNAME = qnameOf("error-tag");
69 private static final QName ERROR_APP_TAG_QNAME = qnameOf("error-app-tag");
70 private static final QName ERROR_MESSAGE_QNAME = qnameOf("error-message");
71 private static final QName ERROR_INFO_QNAME = qnameOf("error-info");
72 private static final QName ERROR_PATH_QNAME = qnameOf("error-path");
73 private static final int DEFAULT_INDENT_SPACES_NUM = 2;
74 private static final XMLOutputFactory XML_OUTPUT_FACTORY;
77 XML_OUTPUT_FACTORY = XMLOutputFactory.newFactory();
78 XML_OUTPUT_FACTORY.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, true);
81 private final DatabindProvider databindProvider;
82 private final ErrorTagMapping errorTagMapping;
85 private HttpHeaders headers;
88 * Initialization of the exception mapper.
90 * @param databindProvider A {@link DatabindProvider}
92 public RestconfDocumentedExceptionMapper(final DatabindProvider databindProvider,
93 final ErrorTagMapping errorTagMapping) {
94 this.databindProvider = requireNonNull(databindProvider);
95 this.errorTagMapping = requireNonNull(errorTagMapping);
99 @SuppressFBWarnings(value = "SLF4J_MANUALLY_PROVIDED_MESSAGE", justification = "In the debug messages "
100 + "we don't to have full stack trace - getMessage(..) method provides finer output.")
101 public Response toResponse(final RestconfDocumentedException exception) {
102 LOG.debug("Starting to map received exception to error response: {}", exception.getMessage());
103 final var responseStatus = getResponseStatusCode(exception);
105 final String serializedResponseBody;
106 final MediaType responseMediaType = transformToResponseMediaType(getSupportedMediaType());
107 if (JaxRsMediaTypes.APPLICATION_YANG_DATA_JSON.equals(responseMediaType)) {
108 serializedResponseBody = serializeExceptionToJson(exception, databindProvider);
110 serializedResponseBody = serializeExceptionToXml(exception, databindProvider);
113 final Response preparedResponse = Response.status(responseStatus.code(), responseStatus.phrase())
114 .type(responseMediaType)
115 .entity(serializedResponseBody)
117 LOG.debug("Exception {} has been successfully mapped to response: {}",
118 exception.getMessage(), preparedResponse);
119 return preparedResponse;
123 * Serialization exceptions into JSON representation.
125 * @param exception To be serialized exception.
126 * @param databindProvider Holder of current {@code DatabindContext}.
127 * @return JSON representation of the exception.
129 private static String serializeExceptionToJson(final RestconfDocumentedException exception,
130 final DatabindProvider databindProvider) {
131 try (var outputStream = new ByteArrayOutputStream();
132 var streamWriter = new OutputStreamWriter(outputStream, StandardCharsets.UTF_8);
133 var jsonWriter = JsonWriterFactory.createJsonWriter(streamWriter, DEFAULT_INDENT_SPACES_NUM)) {
134 final var currentDatabindContext = exception.modelContext() != null
135 ? DatabindContext.ofModel(exception.modelContext()) : databindProvider.currentDatabind();
136 jsonWriter.beginObject();
137 final var errors = exception.getErrors();
138 if (errors != null && !errors.isEmpty()) {
139 jsonWriter.name(Errors.QNAME.getLocalName()).beginObject();
140 jsonWriter.name(Error.QNAME.getLocalName()).beginArray();
141 for (final var error : errors) {
142 jsonWriter.beginObject()
143 .name(ERROR_TAG_QNAME.getLocalName()).value(error.getErrorTag().elementBody());
144 final var errorAppTag = error.getErrorAppTag();
145 if (errorAppTag != null) {
146 jsonWriter.name(ERROR_APP_TAG_QNAME.getLocalName()).value(errorAppTag);
148 final var errorInfo = error.getErrorInfo();
149 if (errorInfo != null) {
150 jsonWriter.name(ERROR_INFO_QNAME.getLocalName()).value(errorInfo);
152 final var errorMessage = error.getErrorMessage();
153 if (errorMessage != null) {
154 jsonWriter.name(ERROR_MESSAGE_QNAME.getLocalName()).value(errorMessage);
156 final var errorPath = error.getErrorPath();
157 if (errorPath != null) {
158 jsonWriter.name(ERROR_PATH_QNAME.getLocalName());
159 currentDatabindContext.jsonCodecs().instanceIdentifierCodec()
160 .writeValue(jsonWriter, errorPath);
162 jsonWriter.name(ERROR_TYPE_QNAME.getLocalName()).value(error.getErrorType().elementBody());
163 jsonWriter.endObject();
165 jsonWriter.endArray().endObject();
167 jsonWriter.endObject();
168 streamWriter.flush();
169 return outputStream.toString(StandardCharsets.UTF_8);
170 } catch (IOException e) {
171 throw new IllegalStateException("Error while serializing restconf exception into JSON", e);
176 * Serialization exceptions into XML representation.
178 * @param exception To be serialized exception.
179 * @param databindProvider Holder of current {@code DatabindContext}.
180 * @return XML representation of the exception.
182 private static String serializeExceptionToXml(final RestconfDocumentedException exception,
183 final DatabindProvider databindProvider) {
184 try (var outputStream = new ByteArrayOutputStream()) {
185 final var xmlWriter = XML_OUTPUT_FACTORY.createXMLStreamWriter(outputStream,
186 StandardCharsets.UTF_8.name());
187 final var currentDatabindContext = exception.modelContext() != null
188 ? DatabindContext.ofModel(exception.modelContext()) : databindProvider.currentDatabind();
189 xmlWriter.writeStartDocument();
190 xmlWriter.writeStartElement(Errors.QNAME.getLocalName());
191 xmlWriter.writeDefaultNamespace(Errors.QNAME.getNamespace().toString());
192 if (exception.getErrors() != null && !exception.getErrors().isEmpty()) {
193 for (final var error : exception.getErrors()) {
194 xmlWriter.writeStartElement(Error.QNAME.getLocalName());
195 // Write error-type element
196 xmlWriter.writeStartElement(ERROR_TYPE_QNAME.getLocalName());
197 xmlWriter.writeCharacters(error.getErrorType().elementBody());
198 xmlWriter.writeEndElement();
200 if (error.getErrorPath() != null) {
201 xmlWriter.writeStartElement(ERROR_PATH_QNAME.getLocalName());
202 currentDatabindContext.xmlCodecs().instanceIdentifierCodec()
203 .writeValue(xmlWriter, error.getErrorPath());
204 xmlWriter.writeEndElement();
206 if (error.getErrorMessage() != null) {
207 xmlWriter.writeStartElement(ERROR_MESSAGE_QNAME.getLocalName());
208 xmlWriter.writeCharacters(error.getErrorMessage());
209 xmlWriter.writeEndElement();
212 // Write error-tag element
213 xmlWriter.writeStartElement(ERROR_TAG_QNAME.getLocalName());
214 xmlWriter.writeCharacters(error.getErrorTag().elementBody());
215 xmlWriter.writeEndElement();
217 if (error.getErrorAppTag() != null) {
218 xmlWriter.writeStartElement(ERROR_APP_TAG_QNAME.getLocalName());
219 xmlWriter.writeCharacters(error.getErrorAppTag());
220 xmlWriter.writeEndElement();
222 if (error.getErrorInfo() != null) {
223 xmlWriter.writeStartElement(ERROR_INFO_QNAME.getLocalName());
224 xmlWriter.writeCharacters(error.getErrorInfo());
225 xmlWriter.writeEndElement();
227 xmlWriter.writeEndElement();
230 xmlWriter.writeEndElement();
231 xmlWriter.writeEndDocument();
234 final var transformerFactory = TransformerFactory.newInstance();
235 final var transformer = transformerFactory.newTransformer();
236 transformer.setOutputProperty(OutputKeys.INDENT, "yes");
237 // 2 spaces for indentation
238 transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount",
239 String.valueOf(DEFAULT_INDENT_SPACES_NUM));
240 transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
241 final var xmlSource = new StreamSource(new StringReader(outputStream.toString(StandardCharsets.UTF_8)));
242 final var stringWriter = new StringWriter();
243 final var streamResult = new StreamResult(stringWriter);
244 transformer.transform(xmlSource, streamResult);
245 return stringWriter.toString();
246 } catch (IOException | XMLStreamException | TransformerException e) {
247 throw new IllegalStateException("Error while serializing restconf exception into XML", e);
252 * Deriving of the status code from the thrown exception. At the first step, status code is tried to be read using
253 * {@link RestconfDocumentedException#getStatus()}. If it is {@code null}, status code will be derived from status
254 * codes appended to error entries (the first that will be found). If there are not any error entries,
255 * {@link HttpStatusCode#INTERNAL_SERVER_ERROR} will be used.
257 * @param exception Thrown exception.
258 * @return Derived status code.
260 private HttpStatusCode getResponseStatusCode(final RestconfDocumentedException exception) {
261 final var errors = exception.getErrors();
262 if (errors.isEmpty()) {
263 // if the module, that thrown exception, doesn't specify status code, it is treated as internal
265 return HttpStatusCode.INTERNAL_SERVER_ERROR;
268 final var allStatusCodesOfErrorEntries = errors.stream()
269 .map(restconfError -> errorTagMapping.statusOf(restconfError.getErrorTag()))
270 // we would like to preserve iteration order in collected entries - hence usage of LinkedHashSet
271 .collect(Collectors.toCollection(LinkedHashSet::new));
272 // choosing of the first status code from appended errors, if there are different status codes in error
273 // entries, we should create WARN message
274 if (allStatusCodesOfErrorEntries.size() > 1) {
276 An unexpected error occurred during translation of exception {} to response: Different status codes
277 have been found in appended error entries: {}. The first error entry status code is chosen for
278 response.""", exception, allStatusCodesOfErrorEntries);
280 return allStatusCodesOfErrorEntries.iterator().next();
284 * Selection of media type that will be used for creation suffix of 'application/yang-data'. Selection criteria
285 * is described in RFC 8040, section 7.1. At the first step, accepted media-type is analyzed and only supported
286 * media-types are filtered out. If both XML and JSON media-types are accepted, JSON is selected as a default one
287 * used in RESTCONF. If accepted-media type is not specified, the media-type used in request is chosen only if it
288 * is supported one. If it is not supported or it is not specified, again, the default one (JSON) is selected.
290 * @return Media type.
292 private MediaType getSupportedMediaType() {
293 final Set<MediaType> acceptableAndSupportedMediaTypes = headers.getAcceptableMediaTypes().stream()
294 .filter(RestconfDocumentedExceptionMapper::isCompatibleMediaType)
295 .collect(Collectors.toSet());
296 if (acceptableAndSupportedMediaTypes.isEmpty()) {
297 // check content type of the request
298 final MediaType requestMediaType = headers.getMediaType();
299 return requestMediaType == null ? DEFAULT_MEDIA_TYPE
300 : chooseMediaType(Collections.singletonList(requestMediaType)).orElseGet(() -> {
301 LOG.warn("Request doesn't specify accepted media-types and the media-type '{}' used by "
302 + "request is not supported - using of default '{}' media-type.",
303 requestMediaType, DEFAULT_MEDIA_TYPE);
304 return DEFAULT_MEDIA_TYPE;
308 // at first step, fully specified types without any wildcards are considered (for example, application/json)
309 final List<MediaType> fullySpecifiedMediaTypes = acceptableAndSupportedMediaTypes.stream()
310 .filter(mediaType -> !mediaType.isWildcardType() && !mediaType.isWildcardSubtype())
311 .collect(Collectors.toList());
312 if (!fullySpecifiedMediaTypes.isEmpty()) {
313 return chooseAndCheckMediaType(fullySpecifiedMediaTypes);
316 // at the second step, only types with specified subtype are considered (for example, */json)
317 final List<MediaType> mediaTypesWithSpecifiedSubtypes = acceptableAndSupportedMediaTypes.stream()
318 .filter(mediaType -> !mediaType.isWildcardSubtype())
319 .collect(Collectors.toList());
320 if (!mediaTypesWithSpecifiedSubtypes.isEmpty()) {
321 return chooseAndCheckMediaType(mediaTypesWithSpecifiedSubtypes);
324 // at the third step, only types with specified parent are considered (for example, application/*)
325 final List<MediaType> mediaTypesWithSpecifiedParent = acceptableAndSupportedMediaTypes.stream()
326 .filter(mediaType -> !mediaType.isWildcardType())
327 .collect(Collectors.toList());
328 if (!mediaTypesWithSpecifiedParent.isEmpty()) {
329 return chooseAndCheckMediaType(mediaTypesWithSpecifiedParent);
332 // it must be fully-wildcard-ed type - */*
333 return DEFAULT_MEDIA_TYPE;
336 private static MediaType chooseAndCheckMediaType(final List<MediaType> options) {
337 return chooseMediaType(options).orElseThrow(IllegalStateException::new);
341 * This method is responsible for choosing of he media type from multiple options. At the first step,
342 * JSON-compatible types are considered, then, if there are not any JSON types, XML types are considered. The first
343 * compatible media-type is chosen.
345 * @param options Supported media types.
346 * @return Selected one media type or {@link Optional#empty()} if none of the provided options are compatible with
349 private static Optional<MediaType> chooseMediaType(final List<MediaType> options) {
350 return options.stream()
351 .filter(RestconfDocumentedExceptionMapper::isJsonCompatibleMediaType)
354 .orElse(options.stream()
355 .filter(RestconfDocumentedExceptionMapper::isXmlCompatibleMediaType)
360 * Mapping of JSON-compatible type to {@link RestconfDocumentedExceptionMapper#YANG_DATA_JSON_TYPE}
361 * or XML-compatible type to {@link RestconfDocumentedExceptionMapper#YANG_DATA_XML_TYPE}.
363 * @param mediaTypeBase Base media type from which the response media-type is built.
364 * @return Derived media type.
366 private static MediaType transformToResponseMediaType(final MediaType mediaTypeBase) {
367 if (isJsonCompatibleMediaType(mediaTypeBase)) {
368 return JaxRsMediaTypes.APPLICATION_YANG_DATA_JSON;
369 } else if (isXmlCompatibleMediaType(mediaTypeBase)) {
370 return JaxRsMediaTypes.APPLICATION_YANG_DATA_XML;
372 throw new IllegalStateException(String.format("Unexpected input media-type %s "
373 + "- it should be JSON/XML compatible type.", mediaTypeBase));
377 private static boolean isCompatibleMediaType(final MediaType mediaType) {
378 return isJsonCompatibleMediaType(mediaType) || isXmlCompatibleMediaType(mediaType);
381 private static boolean isJsonCompatibleMediaType(final MediaType mediaType) {
382 return mediaType.isCompatible(MediaType.APPLICATION_JSON_TYPE)
383 || mediaType.isCompatible(JaxRsMediaTypes.APPLICATION_YANG_DATA_JSON)
384 || mediaType.isCompatible(JaxRsMediaTypes.APPLICATION_YANG_PATCH_JSON);
387 private static boolean isXmlCompatibleMediaType(final MediaType mediaType) {
388 return mediaType.isCompatible(MediaType.APPLICATION_XML_TYPE)
389 || mediaType.isCompatible(JaxRsMediaTypes.APPLICATION_YANG_DATA_XML)
390 || mediaType.isCompatible(JaxRsMediaTypes.APPLICATION_YANG_PATCH_XML);
394 * Used just for testing purposes - simulation of HTTP headers with different accepted types and content type.
396 * @param httpHeaders Mocked HTTP headers.
399 void setHttpHeaders(final HttpHeaders httpHeaders) {
400 headers = httpHeaders;