restconf/restconf-common/src/main/java/org/opendaylight/restconf/common/ErrorTags.java

   1 /*
   2  * Copyright (c) 2021 PANTHEON.tech, s.r.o. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.restconf.common;
   9
  10 import static java.util.Objects.requireNonNull;
  11
  12 import com.google.common.annotations.Beta;
  13 import com.google.common.collect.ImmutableMap;
  14 import javax.ws.rs.core.Response.Status;
  15 import org.eclipse.jdt.annotation.NonNullByDefault;
  16 import org.opendaylight.yangtools.yang.common.ErrorTag;
  17 import org.slf4j.Logger;
  18 import org.slf4j.LoggerFactory;
  19
  20 /**
  21  * {@link ErrorTag} mapping to HTTP errors. Aside from the mappings defined by
  22  * <a href="https://datatracker.ietf.org/doc/html/rfc8040#section-7">RFC8040 section 7</a>, we also define tags which
  23  * map to useful {@link Status} codes.
  24  */
  25 @Beta
  26 @NonNullByDefault
  27 public final class ErrorTags {
  28     /**
  29      * Error reported when the request is valid, but the resource cannot be accessed. This tag typically maps to
  30      * {@link Status#SERVICE_UNAVAILABLE}.
  31      */
  32     // FIXME: redefine as SERVICE_UNAVAILABLE? It would be more obvious
  33     public static final ErrorTag RESOURCE_DENIED_TRANSPORT = new ErrorTag("resource-denied-transport");
  34
  35     private static final Logger LOG = LoggerFactory.getLogger(ErrorTags.class);
  36     private static final ImmutableMap<ErrorTag, Status> WELL_KNOWN_ERROR_TAGS = ImmutableMap.<ErrorTag, Status>builder()
  37         .put(ErrorTag.IN_USE,                     Status.CONFLICT)
  38         .put(ErrorTag.INVALID_VALUE,              Status.BAD_REQUEST)
  39         .put(ErrorTag.TOO_BIG,                    Status.REQUEST_ENTITY_TOO_LARGE)
  40         .put(ErrorTag.MISSING_ATTRIBUTE,          Status.BAD_REQUEST)
  41         .put(ErrorTag.BAD_ATTRIBUTE,              Status.BAD_REQUEST)
  42         .put(ErrorTag.UNKNOWN_ATTRIBUTE,          Status.BAD_REQUEST)
  43         .put(ErrorTag.MISSING_ELEMENT,            Status.BAD_REQUEST)
  44         .put(ErrorTag.BAD_ELEMENT,                Status.BAD_REQUEST)
  45         .put(ErrorTag.UNKNOWN_ELEMENT,            Status.BAD_REQUEST)
  46         .put(ErrorTag.UNKNOWN_NAMESPACE,          Status.BAD_REQUEST)
  47
  48         .put(ErrorTag.ACCESS_DENIED,              Status.FORBIDDEN)
  49         .put(ErrorTag.LOCK_DENIED,                Status.CONFLICT)
  50         .put(ErrorTag.RESOURCE_DENIED,            Status.CONFLICT)
  51         .put(ErrorTag.ROLLBACK_FAILED,            Status.INTERNAL_SERVER_ERROR)
  52         .put(ErrorTag.DATA_EXISTS,                Status.CONFLICT)
  53         .put(ErrorTag.DATA_MISSING,               dataMissingHttpStatus())
  54
  55         .put(ErrorTag.OPERATION_NOT_SUPPORTED,    Status.NOT_IMPLEMENTED)
  56         .put(ErrorTag.OPERATION_FAILED,           Status.INTERNAL_SERVER_ERROR)
  57         .put(ErrorTag.PARTIAL_OPERATION,          Status.INTERNAL_SERVER_ERROR)
  58         .put(ErrorTag.MALFORMED_MESSAGE,          Status.BAD_REQUEST)
  59         .put(ErrorTags.RESOURCE_DENIED_TRANSPORT, Status.SERVICE_UNAVAILABLE)
  60         .build();
  61
  62     private ErrorTags() {
  63         // Hidden on purpose
  64     }
  65
  66     /**
  67      * Return the HTTP {@link Status} corresponding to specified {@link ErrorTag}.
  68      *
  69      * @param tag Error tag to map
  70      * @return HTTP Status
  71      * @throws NullPointerException if {@code tag} is null
  72      */
  73     public static Status statusOf(final ErrorTag tag) {
  74         final Status known = WELL_KNOWN_ERROR_TAGS.get(requireNonNull(tag));
  75         return known != null ? known : Status.INTERNAL_SERVER_ERROR;
  76     }
  77
  78     private static Status dataMissingHttpStatus() {
  79         // Control over the HTTP status reported on "data-missing" conditions. This defaults to disabled,
  80         // HTTP status 409 as specified by RFC8040 (and all previous drafts). See the discussion in:
  81         // https://www.rfc-editor.org/errata/eid5565
  82         // https://mailarchive.ietf.org/arch/msg/netconf/hkVDdHK4xA74NgvXzWP0zObMiyY/
  83         final String propName = "org.opendaylight.restconf.eid5565";
  84         final String propValue = System.getProperty(propName, "disabled");
  85         switch (propValue) {
  86             case "enabled":
  87                 // RFC7231 interpretation: 404 Not Found
  88                 LOG.info("RESTCONF data-missing condition is reported as HTTP status 404 (Errata 5565)");
  89                 return Status.NOT_FOUND;
  90             case "disabled":
  91                 break;
  92             default:
  93                 LOG.warn("Unhandled {} value \"{}\", assuming disabled", propName, propValue);
  94         }
  95
  96         // RFC8040 specification: 409 Conflict
  97         return Status.CONFLICT;
  98     }
  99 }