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 com.google.common.base.Preconditions.checkState;
11 import static org.opendaylight.yang.gen.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.nio.charset.StandardCharsets;
19 import java.util.Collections;
20 import java.util.LinkedHashSet;
21 import java.util.List;
22 import java.util.Optional;
24 import java.util.stream.Collectors;
25 import javax.ws.rs.core.Context;
26 import javax.ws.rs.core.HttpHeaders;
27 import javax.ws.rs.core.MediaType;
28 import javax.ws.rs.core.Response;
29 import javax.ws.rs.core.Response.Status;
30 import javax.ws.rs.ext.ExceptionMapper;
31 import javax.ws.rs.ext.Provider;
32 import org.opendaylight.restconf.common.ErrorTags;
33 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
34 import org.opendaylight.restconf.common.errors.RestconfError;
35 import org.opendaylight.restconf.nb.rfc8040.MediaTypes;
36 import org.opendaylight.restconf.nb.rfc8040.handlers.SchemaContextHandler;
37 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.restconf.rev170126.errors.Errors;
38 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.restconf.rev170126.errors.errors.Error;
39 import org.opendaylight.yangtools.yang.common.QName;
40 import org.opendaylight.yangtools.yang.common.XMLNamespace;
41 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
42 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
43 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
44 import org.opendaylight.yangtools.yang.data.api.schema.UnkeyedListEntryNode;
45 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
46 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
47 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
48 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
49 import org.slf4j.Logger;
50 import org.slf4j.LoggerFactory;
53 * Mapper that is responsible for transformation of thrown {@link RestconfDocumentedException} to errors structure
54 * that is modelled by RESTCONF module (see section 8 of RFC-8040).
57 public final class RestconfDocumentedExceptionMapper implements ExceptionMapper<RestconfDocumentedException> {
58 private static final Logger LOG = LoggerFactory.getLogger(RestconfDocumentedExceptionMapper.class);
59 private static final MediaType DEFAULT_MEDIA_TYPE = MediaType.APPLICATION_JSON_TYPE;
60 private static final Status DEFAULT_STATUS_CODE = Status.INTERNAL_SERVER_ERROR;
61 // Note: we are using container's QName reference to trim imports
62 private static final SchemaPath ERRORS_GROUPING_PATH = SchemaPath.create(true, Errors.QNAME);
63 private static final QName ERROR_TYPE_QNAME = qnameOf("error-type");
64 private static final QName ERROR_TAG_QNAME = qnameOf("error-tag");
65 private static final QName ERROR_APP_TAG_QNAME = qnameOf("error-app-tag");
66 private static final QName ERROR_MESSAGE_QNAME = qnameOf("error-message");
67 private static final QName ERROR_INFO_QNAME = qnameOf("error-info");
68 private static final QName ERROR_PATH_QNAME = qnameOf("error-path");
69 private static final XMLNamespace IETF_RESTCONF_URI = Errors.QNAME.getModule().getNamespace();
72 private HttpHeaders headers;
73 private final SchemaContextHandler schemaContextHandler;
76 * Initialization of the exception mapper.
78 * @param schemaContextHandler Handler that provides actual schema context.
80 public RestconfDocumentedExceptionMapper(final SchemaContextHandler schemaContextHandler) {
81 this.schemaContextHandler = schemaContextHandler;
85 @SuppressFBWarnings(value = "SLF4J_MANUALLY_PROVIDED_MESSAGE", justification = "In the debug messages "
86 + "we don't to have full stack trace - getMessage(..) method provides finer output.")
87 public Response toResponse(final RestconfDocumentedException exception) {
88 LOG.debug("Starting to map received exception to error response: {}", exception.getMessage());
89 final Status responseStatus = getResponseStatusCode(exception);
90 if (responseStatus != Response.Status.FORBIDDEN
91 && responseStatus.getFamily() == Response.Status.Family.CLIENT_ERROR
92 && exception.getErrors().isEmpty()) {
93 // There should be at least one error entry for 4xx errors except 409 according to RFC8040, but we do not
94 // have it. Issue a warning with the call trace so we can fix whoever was the originator.
95 LOG.warn("Input exception has a family of 4xx but does not contain any descriptive errors", exception);
98 final ContainerNode errorsContainer = buildErrorsContainer(exception);
99 final String serializedResponseBody;
100 final MediaType responseMediaType = transformToResponseMediaType(getSupportedMediaType());
101 if (MediaTypes.APPLICATION_YANG_DATA_JSON_TYPE.equals(responseMediaType)) {
102 serializedResponseBody = serializeErrorsContainerToJson(errorsContainer);
104 serializedResponseBody = serializeErrorsContainerToXml(errorsContainer);
107 final Response preparedResponse = Response.status(responseStatus)
108 .type(responseMediaType)
109 .entity(serializedResponseBody)
111 LOG.debug("Exception {} has been successfully mapped to response: {}",
112 exception.getMessage(), preparedResponse);
113 return preparedResponse;
117 * Filling up of the errors container with data from input {@link RestconfDocumentedException}.
119 * @param exception Thrown exception.
120 * @return Built errors container.
122 private static ContainerNode buildErrorsContainer(final RestconfDocumentedException exception) {
123 return Builders.containerBuilder()
124 .withNodeIdentifier(NodeIdentifier.create(Errors.QNAME))
125 .withChild(Builders.unkeyedListBuilder()
126 .withNodeIdentifier(NodeIdentifier.create(Error.QNAME))
127 .withValue(exception.getErrors().stream()
128 .map(RestconfDocumentedExceptionMapper::createErrorEntry)
129 .collect(Collectors.toList()))
135 * Building of one error entry using provided {@link RestconfError}.
137 * @param restconfError Error details.
138 * @return Built list entry.
140 private static UnkeyedListEntryNode createErrorEntry(final RestconfError restconfError) {
141 // filling in mandatory leafs
142 final var entryBuilder = Builders.unkeyedListEntryBuilder()
143 .withNodeIdentifier(NodeIdentifier.create(Error.QNAME))
144 .withChild(ImmutableNodes.leafNode(ERROR_TYPE_QNAME, restconfError.getErrorType().elementBody()))
145 .withChild(ImmutableNodes.leafNode(ERROR_TAG_QNAME, restconfError.getErrorTag().elementBody()));
147 // filling in optional fields
148 if (restconfError.getErrorMessage() != null) {
149 entryBuilder.withChild(ImmutableNodes.leafNode(ERROR_MESSAGE_QNAME, restconfError.getErrorMessage()));
151 if (restconfError.getErrorAppTag() != null) {
152 entryBuilder.withChild(ImmutableNodes.leafNode(ERROR_APP_TAG_QNAME, restconfError.getErrorAppTag()));
154 if (restconfError.getErrorInfo() != null) {
155 // Oddly, error-info is defined as an empty container in the restconf yang. Apparently the
156 // intention is for implementors to define their own data content so we'll just treat it as a leaf
158 entryBuilder.withChild(ImmutableNodes.leafNode(ERROR_INFO_QNAME, restconfError.getErrorInfo()));
161 if (restconfError.getErrorPath() != null) {
162 entryBuilder.withChild(ImmutableNodes.leafNode(ERROR_PATH_QNAME, restconfError.getErrorPath()));
164 return entryBuilder.build();
168 * Serialization of the errors container into JSON representation.
170 * @param errorsContainer To be serialized errors container.
171 * @return JSON representation of the errors container.
173 private String serializeErrorsContainerToJson(final ContainerNode errorsContainer) {
174 try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
175 OutputStreamWriter streamStreamWriter = new OutputStreamWriter(outputStream, StandardCharsets.UTF_8);
177 return writeNormalizedNode(errorsContainer, outputStream, new JsonStreamWriterWithDisabledValidation(
178 ERROR_INFO_QNAME, streamStreamWriter, ERRORS_GROUPING_PATH, IETF_RESTCONF_URI, schemaContextHandler));
179 } catch (IOException e) {
180 throw new IllegalStateException("Cannot close some of the output JSON writers", e);
185 * Serialization of the errors container into XML representation.
187 * @param errorsContainer To be serialized errors container.
188 * @return XML representation of the errors container.
190 private String serializeErrorsContainerToXml(final ContainerNode errorsContainer) {
191 try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
192 return writeNormalizedNode(errorsContainer, outputStream, new XmlStreamWriterWithDisabledValidation(
193 ERROR_INFO_QNAME, outputStream, ERRORS_GROUPING_PATH, schemaContextHandler));
194 } catch (IOException e) {
195 throw new IllegalStateException("Cannot close some of the output XML writers", e);
199 private static String writeNormalizedNode(final NormalizedNode errorsContainer,
200 final ByteArrayOutputStream outputStream, final StreamWriterWithDisabledValidation streamWriter) {
201 try (NormalizedNodeWriter nnWriter = NormalizedNodeWriter.forStreamWriter(streamWriter)) {
202 nnWriter.write(errorsContainer);
203 } catch (IOException e) {
204 throw new IllegalStateException("Cannot write error response body", e);
206 return outputStream.toString(StandardCharsets.UTF_8);
210 * Deriving of the status code from the thrown exception. At the first step, status code is tried to be read using
211 * {@link RestconfDocumentedException#getStatus()}. If it is {@code null}, status code will be derived from status
212 * codes appended to error entries (the first that will be found). If there are not any error entries,
213 * {@link RestconfDocumentedExceptionMapper#DEFAULT_STATUS_CODE} will be used.
215 * @param exception Thrown exception.
216 * @return Derived status code.
218 private static Status getResponseStatusCode(final RestconfDocumentedException exception) {
219 final Status status = exception.getStatus();
220 if (status != null) {
221 // status code that is specified directly as field in exception has the precedence over error entries
225 final List<RestconfError> errors = exception.getErrors();
226 if (errors.isEmpty()) {
227 // if the module, that thrown exception, doesn't specify status code, it is treated as internal
229 return DEFAULT_STATUS_CODE;
232 final Set<Status> allStatusCodesOfErrorEntries = errors.stream()
233 .map(restconfError -> ErrorTags.statusOf(restconfError.getErrorTag()))
234 // we would like to preserve iteration order in collected entries - hence usage of LinkedHashSet
235 .collect(Collectors.toCollection(LinkedHashSet::new));
236 // choosing of the first status code from appended errors, if there are different status codes in error
237 // entries, we should create WARN message
238 if (allStatusCodesOfErrorEntries.size() > 1) {
239 LOG.warn("An unexpected error occurred during translation of exception {} to response: "
240 + "Different status codes have been found in appended error entries: {}. The first error "
241 + "entry status code is chosen for response.", exception, allStatusCodesOfErrorEntries);
243 return allStatusCodesOfErrorEntries.iterator().next();
247 * Selection of media type that will be used for creation suffix of 'application/yang-data'. Selection criteria
248 * is described in RFC 8040, section 7.1. At the first step, accepted media-type is analyzed and only supported
249 * media-types are filtered out. If both XML and JSON media-types are accepted, JSON is selected as a default one
250 * used in RESTCONF. If accepted-media type is not specified, the media-type used in request is chosen only if it
251 * is supported one. If it is not supported or it is not specified, again, the default one (JSON) is selected.
253 * @return Media type.
255 private MediaType getSupportedMediaType() {
256 final Set<MediaType> acceptableAndSupportedMediaTypes = headers.getAcceptableMediaTypes().stream()
257 .filter(RestconfDocumentedExceptionMapper::isCompatibleMediaType)
258 .collect(Collectors.toSet());
259 if (acceptableAndSupportedMediaTypes.isEmpty()) {
260 // check content type of the request
261 final MediaType requestMediaType = headers.getMediaType();
262 return requestMediaType == null ? DEFAULT_MEDIA_TYPE
263 : chooseMediaType(Collections.singletonList(requestMediaType)).orElseGet(() -> {
264 LOG.warn("Request doesn't specify accepted media-types and the media-type '{}' used by "
265 + "request is not supported - using of default '{}' media-type.",
266 requestMediaType, DEFAULT_MEDIA_TYPE);
267 return DEFAULT_MEDIA_TYPE;
271 // at first step, fully specified types without any wildcards are considered (for example, application/json)
272 final List<MediaType> fullySpecifiedMediaTypes = acceptableAndSupportedMediaTypes.stream()
273 .filter(mediaType -> !mediaType.isWildcardType() && !mediaType.isWildcardSubtype())
274 .collect(Collectors.toList());
275 if (!fullySpecifiedMediaTypes.isEmpty()) {
276 return chooseAndCheckMediaType(fullySpecifiedMediaTypes);
279 // at the second step, only types with specified subtype are considered (for example, */json)
280 final List<MediaType> mediaTypesWithSpecifiedSubtypes = acceptableAndSupportedMediaTypes.stream()
281 .filter(mediaType -> !mediaType.isWildcardSubtype())
282 .collect(Collectors.toList());
283 if (!mediaTypesWithSpecifiedSubtypes.isEmpty()) {
284 return chooseAndCheckMediaType(mediaTypesWithSpecifiedSubtypes);
287 // at the third step, only types with specified parent are considered (for example, application/*)
288 final List<MediaType> mediaTypesWithSpecifiedParent = acceptableAndSupportedMediaTypes.stream()
289 .filter(mediaType -> !mediaType.isWildcardType())
290 .collect(Collectors.toList());
291 if (!mediaTypesWithSpecifiedParent.isEmpty()) {
292 return chooseAndCheckMediaType(mediaTypesWithSpecifiedParent);
295 // it must be fully-wildcard-ed type - */*
296 return DEFAULT_MEDIA_TYPE;
299 private static MediaType chooseAndCheckMediaType(final List<MediaType> options) {
300 final Optional<MediaType> mediaTypeOpt = chooseMediaType(options);
301 checkState(mediaTypeOpt.isPresent());
302 return mediaTypeOpt.get();
306 * This method is responsible for choosing of he media type from multiple options. At the first step,
307 * JSON-compatible types are considered, then, if there are not any JSON types, XML types are considered. The first
308 * compatible media-type is chosen.
310 * @param options Supported media types.
311 * @return Selected one media type or {@link Optional#empty()} if none of the provided options are compatible with
314 private static Optional<MediaType> chooseMediaType(final List<MediaType> options) {
315 return options.stream()
316 .filter(RestconfDocumentedExceptionMapper::isJsonCompatibleMediaType)
319 .orElse(options.stream()
320 .filter(RestconfDocumentedExceptionMapper::isXmlCompatibleMediaType)
325 * Mapping of JSON-compatible type to {@link RestconfDocumentedExceptionMapper#YANG_DATA_JSON_TYPE}
326 * or XML-compatible type to {@link RestconfDocumentedExceptionMapper#YANG_DATA_XML_TYPE}.
328 * @param mediaTypeBase Base media type from which the response media-type is built.
329 * @return Derived media type.
331 private static MediaType transformToResponseMediaType(final MediaType mediaTypeBase) {
332 if (isJsonCompatibleMediaType(mediaTypeBase)) {
333 return MediaTypes.APPLICATION_YANG_DATA_JSON_TYPE;
334 } else if (isXmlCompatibleMediaType(mediaTypeBase)) {
335 return MediaTypes.APPLICATION_YANG_DATA_XML_TYPE;
337 throw new IllegalStateException(String.format("Unexpected input media-type %s "
338 + "- it should be JSON/XML compatible type.", mediaTypeBase));
342 private static boolean isCompatibleMediaType(final MediaType mediaType) {
343 return isJsonCompatibleMediaType(mediaType) || isXmlCompatibleMediaType(mediaType);
346 private static boolean isJsonCompatibleMediaType(final MediaType mediaType) {
347 return mediaType.isCompatible(MediaType.APPLICATION_JSON_TYPE)
348 || mediaType.isCompatible(MediaTypes.APPLICATION_YANG_DATA_JSON_TYPE)
349 || mediaType.isCompatible(MediaTypes.APPLICATION_YANG_PATCH_JSON_TYPE);
352 private static boolean isXmlCompatibleMediaType(final MediaType mediaType) {
353 return mediaType.isCompatible(MediaType.APPLICATION_XML_TYPE)
354 || mediaType.isCompatible(MediaTypes.APPLICATION_YANG_DATA_XML_TYPE)
355 || mediaType.isCompatible(MediaTypes.APPLICATION_YANG_PATCH_XML_TYPE);
359 * Used just for testing purposes - simulation of HTTP headers with different accepted types and content type.
361 * @param httpHeaders Mocked HTTP headers.
364 void setHttpHeaders(final HttpHeaders httpHeaders) {
365 headers = httpHeaders;