summaryrefslogtreecommitdiffstats
path: root/infra/data-impl/src/main/java/io/fd/honeycomb/data/impl/ModificationDiff.java
blob: 863f8abb20b36046dfe388acedc299c216c189f9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
/*
 * Copyright (c) 2016 Cisco and/or its affiliates.
 *
 * 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.fd.honeycomb.data.impl;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType.APPEARED;
import static org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType.DELETE;
import static org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType.DISAPPEARED;
import static org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType.WRITE;

import com.google.common.collect.ImmutableMap;
import java.util.Collection;
import java.util.Collections;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.schema.MixinNode;
import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateNode;
import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
import org.opendaylight.yangtools.yang.model.api.AugmentationSchema;
import org.opendaylight.yangtools.yang.model.api.AugmentationTarget;
import org.opendaylight.yangtools.yang.model.api.ChoiceSchemaNode;
import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
import org.opendaylight.yangtools.yang.model.api.LeafListSchemaNode;
import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
import org.opendaylight.yangtools.yang.model.api.SchemaContext;
import org.opendaylight.yangtools.yang.model.api.SchemaNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Recursively collects and provides all unique and non-null modifications (modified normalized nodes).
 */
final class ModificationDiff {

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

    private static final ModificationDiff EMPTY_DIFF = new ModificationDiff(Collections.emptyMap());
    private static final EnumSet VALID_MODIFICATIONS = EnumSet.of(WRITE, DELETE);
    private static final EnumSet IGNORED_MODIFICATIONS = EnumSet.of(APPEARED, DISAPPEARED);

    private final Map<YangInstanceIdentifier, NormalizedNodeUpdate> updates;

    private ModificationDiff(@Nonnull Map<YangInstanceIdentifier, NormalizedNodeUpdate> updates) {
        this.updates = updates;
    }

    /**
     * Get processed modifications.
     *
     * @return mapped modifications, where key is keyed {@link YangInstanceIdentifier}.
     */
    Map<YangInstanceIdentifier, NormalizedNodeUpdate> getUpdates() {
        return updates;
    }

    private ModificationDiff merge(final ModificationDiff other) {
        if (this == EMPTY_DIFF) {
            return other;
        }

        if (other == EMPTY_DIFF) {
            return this;
        }

        return new ModificationDiff(join(updates, other.updates));
    }

    private static Map<YangInstanceIdentifier, NormalizedNodeUpdate> join(
            Map<YangInstanceIdentifier, NormalizedNodeUpdate> first,
            Map<YangInstanceIdentifier, NormalizedNodeUpdate> second) {
        final Map<YangInstanceIdentifier, NormalizedNodeUpdate> merged = new HashMap<>();
        merged.putAll(first);
        merged.putAll(second);
        return merged;
    }

    private static ModificationDiff create(Modification modification) {
        return new ModificationDiff(ImmutableMap.of(modification.getId(), NormalizedNodeUpdate.create(modification)));
    }

    /**
     * Produce an aggregated diff from a candidate node recursively. MixinNodes are ignored as modifications and so
     * are complex nodes which direct leaves were not modified.
     */
    @Nonnull
    static ModificationDiff recursivelyFromCandidate(@Nonnull final Modification modification) {
        // recursively process child nodes for exact modifications
        return recursivelyChildrenFromCandidate(modification)
                // also add modification on current level, if elligible
                .merge(isModification(modification)
                        ? ModificationDiff.create(modification)
                        : EMPTY_DIFF);
    }

    /**
     * Same as {@link #recursivelyFromCandidate(Modification)} but does
     * not process the root node for modifications, since it's the artificial data root, that has no child leaves but
     * always is marked as SUBTREE_MODIFIED.
     */
    @Nonnull
    static ModificationDiff recursivelyFromCandidateRoot(@Nonnull final DataTreeCandidateNode currentCandidate,
                                                         @Nonnull final SchemaContext ctx) {
        return recursivelyChildrenFromCandidate(new Modification(YangInstanceIdentifier.EMPTY, currentCandidate, ctx));
    }

    /**
     * Check whether current node was modified. {@link MixinNode}s are ignored
     * and only nodes which direct leaves(or choices) are modified are considered a modification.
     */
    private static Boolean isModification(@Nonnull final Modification modification) {
        // Disappear is not a modification
        if (IGNORED_MODIFICATIONS.contains(modification.getModificationType())) {
            return false;
        // Mixin nodes are not considered modifications
        } else if (modification.isMixin() && !modification.is(AugmentationSchema.class)) {
            return false;
        } else {
            return isCurrentModified(modification);
        }
    }

    private static Boolean isCurrentModified(@Nonnull final Modification modification) {
        // First check if it's an empty presence node
        final boolean emptyPresenceNode = isEmptyPresenceNode(modification);

        // Check if there are any modified leaves and if so, consider current node as modified
        final Boolean directLeavesModified = emptyPresenceNode
                || modification.streamChildren()
                // Checking leaf or leaf-lists children for direct modification, which means that leafs of leaf lists
                // trigger a modification on parent node
                .filter(child -> child.is(LeafSchemaNode.class) || child.is(LeafListSchemaNode.class))
                // For some reason, we get modifications on unmodified list keys
                // and that messes up our modifications collection here, so we need to skip
                .filter(Modification::isBeforeAndAfterDifferent)
                .filter(child -> VALID_MODIFICATIONS.contains(child.getModificationType()))
                .findFirst()
                .isPresent();

        // Also as fallback check choices (choices do not exist in BA world and if anything within a choice was modified,
        // consider its parent as being modified)
        final boolean modified = directLeavesModified
                || modification.streamChildren()
                .filter(child -> child.is(ChoiceSchemaNode.class))
                // Recursively check each choice if there was any change to it
                .filter(ModificationDiff::isCurrentModified)
                .findFirst()
                .isPresent();

        if (modified) {
            LOG.debug("Modification detected as {} at {}",
                    modification.getModificationType(), modification.getId());
        }

        return modified;
    }

    /**
     * Check if new data are empty but still to be considered as a modification, meaning it's presence has a meaning
     * e.g. containers with presence statement.
     */
    private static boolean isEmptyPresenceNode(@Nonnull final Modification modification) {
        return modification.is(ContainerSchemaNode.class)
                && ((ContainerSchemaNode) modification.getSchemaNode()).isPresenceContainer()
                && modification.getChildNodes().isEmpty()
                && VALID_MODIFICATIONS.contains(modification.getModificationType());
    }

    /**
     * Process all non-leaf child nodes recursively, creating aggregated {@link ModificationDiff}.
     */
    private static ModificationDiff recursivelyChildrenFromCandidate(@Nonnull final Modification modification) {
        // recursively process child nodes for specific modifications
        return modification.streamChildren()
                .filter(child -> !child.is(LeafSchemaNode.class))
                .map(ModificationDiff::recursivelyFromCandidate)
                .reduce(ModificationDiff::merge)
                .orElse(EMPTY_DIFF);
    }

    @Override
    public String toString() {
        return "ModificationDiff{updates=" + updates + '}';
    }

    /**
     * Update to a normalized node identifiable by its {@link YangInstanceIdentifier}.
     */
    static final class NormalizedNodeUpdate {

        @Nonnull
        private final YangInstanceIdentifier id;
        @Nullable
        private final NormalizedNode<?, ?> dataBefore;
        @Nullable
        private final NormalizedNode<?, ?> dataAfter;

        private NormalizedNodeUpdate(@Nonnull final YangInstanceIdentifier id,
                                     @Nullable final NormalizedNode<?, ?> dataBefore,
                                     @Nullable final NormalizedNode<?, ?> dataAfter) {
            this.id = checkNotNull(id);
            this.dataAfter = dataAfter;
            this.dataBefore = dataBefore;
        }

        @Nullable
        public NormalizedNode<?, ?> getDataBefore() {
            return dataBefore;
        }

        @Nullable
        public NormalizedNode<?, ?> getDataAfter() {
            return dataAfter;
        }

        @Nonnull
        public YangInstanceIdentifier getId() {
            return id;
        }

        static NormalizedNodeUpdate create(@Nonnull final Modification modification) {
            final com.google.common.base.Optional<NormalizedNode<?, ?>> beforeData =
                    modification.getDataBefore();
            final com.google.common.base.Optional<NormalizedNode<?, ?>> afterData =
                    modification.getDataAfter();
            checkArgument(beforeData.isPresent() || afterData.isPresent(),
                    "Both before and after data are null for %s", modification.getId());
            return NormalizedNodeUpdate.create(modification.getId(), beforeData.orNull(), afterData.orNull());
        }

        static NormalizedNodeUpdate create(@Nonnull final YangInstanceIdentifier id,
                                           @Nullable final NormalizedNode<?, ?> dataBefore,
                                           @Nullable final NormalizedNode<?, ?> dataAfter) {
            return new NormalizedNodeUpdate(id, dataBefore, dataAfter);
        }

        @Override
        public boolean equals(final Object other) {
            if (this == other) {
                return true;
            }
            if (other == null || getClass() != other.getClass()) {
                return false;
            }

            final NormalizedNodeUpdate that = (NormalizedNodeUpdate) other;

            return id.equals(that.id);

        }

        @Override
        public int hashCode() {
            return id.hashCode();
        }

        @Override
        public String toString() {
            return "NormalizedNodeUpdate{" + "id=" + id
                    + ", dataBefore=" + dataBefore
                    + ", dataAfter=" + dataAfter
                    + '}';
        }
    }

    /**
     * Intermediate representation of a modification + its schema.
     */
    private static final class Modification {
        private final YangInstanceIdentifier id;
        private final DataTreeCandidateNode dataCandidate;
        // Using Object as type for schema node since it's the only type that's a parent to all schema node types from
        // yangtools. The hierarchy does not use e.g. SchemaNode class for all types
        private final Object parentNode;
        private final Object schemaNode;
        private final boolean updateParentNode;

        private Modification(final YangInstanceIdentifier id,
                             final DataTreeCandidateNode dataCandidate,
                             final Object parentNode,
                             final Object schemaNode,
                             final boolean updateParentNode) {
            this.id = id;
            this.dataCandidate = dataCandidate;
            this.parentNode = parentNode;
            this.schemaNode = schemaNode;
            // controls process of updating parent node while moving down the schema tree:
            this.updateParentNode = updateParentNode;
        }

        Modification(final YangInstanceIdentifier id,
                     final DataTreeCandidateNode dataCandidate,
                     final Object parentNode,
                     final Object schemaNode) {
            this(id, dataCandidate, parentNode, schemaNode, true);
        }

        Modification(final YangInstanceIdentifier id,
                     final DataTreeCandidateNode dataCandidate,
                     final Object schemaNode) {
            this(id, dataCandidate, schemaNode, schemaNode);
        }

        List<Modification> getChildNodes() {
            return streamChildren().collect(Collectors.toList());
        }

        YangInstanceIdentifier getId() {
            return id;
        }

        ModificationType getModificationType() {
            return dataCandidate.getModificationType();
        }

        com.google.common.base.Optional<NormalizedNode<?, ?>> getDataBefore() {
            return dataCandidate.getDataBefore();
        }

        com.google.common.base.Optional<NormalizedNode<?, ?>> getDataAfter() {
            return dataCandidate.getDataAfter();
        }

        Object getSchemaNode() {
            return schemaNode;
        }

        boolean is(final Class<?> schemaType) {
            return schemaType.isAssignableFrom(schemaNode.getClass());
        }

        boolean isMixin() {
            // Checking whether node is a mixin is not performed on schema, but on data since mixin is
            // only a NormalizedNode concept, not a schema concept
            return dataCandidate.getDataBefore().orNull() instanceof MixinNode ||
                    dataCandidate.getDataAfter().orNull() instanceof MixinNode;
        }

        private boolean isBeforeAndAfterDifferent() {
            if (dataCandidate.getDataBefore().isPresent()) {
                return !dataCandidate.getDataBefore().get().equals(dataCandidate.getDataAfter().orNull());
            }

            // considering not a modification if data after is also null
            return dataCandidate.getDataAfter().isPresent();
        }

        private AugmentationSchema findAugmentation(Object currentNode,
                                                    final YangInstanceIdentifier.AugmentationIdentifier identifier) {
            if (currentNode != null) {
                // check if identifier points to some augmentation of currentNode
                if (currentNode instanceof AugmentationTarget) {
                    Optional<AugmentationSchema> augmentationSchema =
                        ((AugmentationTarget) currentNode).getAvailableAugmentations().stream()
                            .filter(aug -> identifier.equals(new YangInstanceIdentifier.AugmentationIdentifier(
                                aug.getChildNodes().stream()
                                    .map(SchemaNode::getQName)
                                    .collect(Collectors.toSet()))))
                            .findFirst();
                    if (augmentationSchema.isPresent()) {
                        return augmentationSchema.get();
                    }
                }

                // continue search:
                Collection<DataSchemaNode> childNodes = Collections.emptyList();
                if (currentNode instanceof DataNodeContainer) {
                    childNodes = ((DataNodeContainer) currentNode).getChildNodes();
                } else if (currentNode instanceof ChoiceSchemaNode) {
                    childNodes = ((ChoiceSchemaNode) currentNode).getCases().stream()
                        .flatMap(cas -> cas.getChildNodes().stream()).collect(Collectors.toList());
                }
                return childNodes.stream().map(n -> findAugmentation(n, identifier)).filter(n -> n != null).findFirst()
                    .orElse(null);
            } else {
                return null;
            }
        }

        Stream<Modification> streamChildren() {
            return dataCandidate.getChildNodes().stream()
                .map(child -> {
                    final YangInstanceIdentifier childId = id.node(child.getIdentifier());
                    final Object schemaChild = schemaChild(schemaNode, child.getIdentifier());

                    // An augment cannot change other augment, so we do not update parent node if we are streaming
                    // children of AugmentationSchema (otherwise we would fail to find schema for nested augmentations):
                    if (updateParentNode) {
                        if (schemaNode instanceof AugmentationSchema) {
                            // child nodes would not have nested augmentations, so we stop moving parentNode:
                            return new Modification(childId, child, parentNode, schemaChild, false);
                        } else {
                            // update parent node:
                            return new Modification(childId, child, schemaNode, schemaChild, true);
                        }
                    }
                    return new Modification(childId, child, parentNode, schemaChild, updateParentNode);
                });
        }

        /**
         * Find next schema node in hierarchy.
         */
        private Object schemaChild(final Object schemaNode, final YangInstanceIdentifier.PathArgument identifier) {
            Object found = null;

            if (identifier instanceof YangInstanceIdentifier.AugmentationIdentifier) {
                if (schemaNode instanceof AugmentationTarget) {
                    // Find matching augmentation
                    found = ((AugmentationTarget) schemaNode).getAvailableAugmentations().stream()
                        .filter(aug -> identifier.equals(new YangInstanceIdentifier.AugmentationIdentifier(
                            aug.getChildNodes().stream()
                                .map(SchemaNode::getQName)
                                .collect(Collectors.toSet()))))
                        .findFirst()
                        .orElse(null);

                    if (found == null) {
                        // An augment cannot change other augment, but all augments only change their targets (data nodes).
                        //
                        // As a consequence, if nested augmentations are present,
                        // AugmentationSchema might reference child schema node instances that do not include changes
                        // from nested augments.
                        //
                        // But schemaNode, as mentioned earlier, contains all the changes introduced by augments.
                        //
                        // On the other hand, in case of augments which introduce leaves,
                        // we need to address AugmentationSchema node directly so we can't simply do
                        // found = schemaNode;
                        //
                        found =
                            findAugmentation(parentNode, (YangInstanceIdentifier.AugmentationIdentifier) identifier);
                    }
                }
            } else if (schemaNode instanceof DataNodeContainer) {
                // Special handling for list aggregator nodes. If we are at list aggregator node e.g. MapNode and
                // we are searching for schema for a list entry e.g. MapEntryNode just return the same schema
                if (schemaNode instanceof ListSchemaNode &&
                    ((SchemaNode) schemaNode).getQName().equals(identifier.getNodeType())) {
                    found = schemaNode;
                } else {
                    found = ((DataNodeContainer) schemaNode).getDataChildByName(identifier.getNodeType());
                }
            } else if (schemaNode instanceof ChoiceSchemaNode) {
                // For choices, iterate through all the cases
                final Optional<DataSchemaNode> maybeChild = ((ChoiceSchemaNode) schemaNode).getCases().stream()
                        .flatMap(cas -> cas.getChildNodes().stream())
                        .filter(child -> child.getQName().equals(identifier.getNodeType()))
                        .findFirst();
                if (maybeChild.isPresent()) {
                    found = maybeChild.get();
                }
                // Special handling for leaf-list nodes. Basically the same as is for list mixin nodes
            } else if (schemaNode instanceof LeafListSchemaNode &&
                ((SchemaNode) schemaNode).getQName().equals(identifier.getNodeType())) {
                found = schemaNode;
            }

            return checkNotNull(found, "Unable to find child node in: %s identifiable by: %s", schemaNode, identifier);
        }

        @Override
        public String toString() {
            return "Modification{" +
                    "id=" + id +
                    '}';
        }
    }
}