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A more performant JSON-LD 1.1 Processor & API forked from Titanium JSON-LD.
The newest version!
/*
* Copyright 2020 APICATALOG and HASMAC.
*
* 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.
*
* SPDX-License-Identifier: Apache-2.0
*/
package no.hasmac.jsonld.processor;
import jakarta.json.JsonArray;
import jakarta.json.JsonArrayBuilder;
import jakarta.json.JsonObject;
import jakarta.json.JsonObjectBuilder;
import jakarta.json.JsonString;
import jakarta.json.JsonStructure;
import jakarta.json.JsonValue;
import no.hasmac.jsonld.JsonLdError;
import no.hasmac.jsonld.JsonLdErrorCode;
import no.hasmac.jsonld.JsonLdOptions;
import no.hasmac.jsonld.JsonLdVersion;
import no.hasmac.jsonld.compaction.Compaction;
import no.hasmac.jsonld.context.ActiveContext;
import no.hasmac.jsonld.document.Document;
import no.hasmac.jsonld.flattening.NodeMap;
import no.hasmac.jsonld.flattening.NodeMapBuilder;
import no.hasmac.jsonld.framing.Frame;
import no.hasmac.jsonld.framing.Framing;
import no.hasmac.jsonld.framing.FramingState;
import no.hasmac.jsonld.json.JsonMapBuilder;
import no.hasmac.jsonld.json.JsonProvider;
import no.hasmac.jsonld.json.JsonUtils;
import no.hasmac.jsonld.lang.BlankNode;
import no.hasmac.jsonld.lang.Keywords;
import no.hasmac.jsonld.loader.DocumentLoaderOptions;
import java.net.URI;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.stream.Collectors;
import java.util.stream.Stream;
/**
*
* @see JsonLdProcessor.frame()
*
*/
public final class FramingProcessor {
private FramingProcessor() {
}
public static JsonObject frame(final URI input, final Document frame, final JsonLdOptions options) throws JsonLdError {
if (options.getDocumentLoader() == null) {
throw new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Document loader is null. Cannot fetch [" + input + "].");
}
final DocumentLoaderOptions loaderOptions = new DocumentLoaderOptions();
loaderOptions.setExtractAllScripts(options.isExtractAllScripts());
final Document remoteDocument = options.getDocumentLoader().loadDocument(input, loaderOptions);
if (remoteDocument == null) {
throw new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Returned document is null [" + input + "].");
}
return frame(remoteDocument, frame, options);
}
public static JsonObject frame(final Document input, final URI frameUri, final JsonLdOptions options) throws JsonLdError {
if (options.getDocumentLoader() == null) {
throw new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Document loader is null. Cannot fetch [" + frameUri + "].");
}
final Document frameDocument = options.getDocumentLoader().loadDocument(frameUri, new DocumentLoaderOptions());
if (frameDocument == null) {
throw new JsonLdError(JsonLdErrorCode.INVALID_REMOTE_CONTEXT, "Returned frame is null [" + frameUri + "] is null.");
}
return frame(input, frameDocument, options);
}
public static JsonObject frame(final Document input, final Document frame, final JsonLdOptions options) throws JsonLdError {
if (frame == null) {
throw new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Frame or Frame.Document is null.");
}
final JsonStructure frameStructure =
frame
.getJsonContent()
.orElseThrow(() -> new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Frame is not JSON object but null."));
if (JsonUtils.isNotObject(frameStructure)) {
throw new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Frame is not JSON object but [" + frameStructure + "].");
}
final JsonObject frameObject = frameStructure.asJsonObject();
// 4.
final JsonLdOptions expansionOptions = new JsonLdOptions(options);
expansionOptions.setOrdered(false);
JsonArray expandedInput = ExpansionProcessor.expand(input, expansionOptions, false);
// 7.
JsonArray expandedFrame = ExpansionProcessor.expand(frame, expansionOptions, true);
JsonValue context = JsonValue.EMPTY_JSON_OBJECT;
if (frameObject.containsKey(Keywords.CONTEXT)
) {
context = frameObject.get(Keywords.CONTEXT);
}
// 9.
final URI contextBase = (frame.getContextUrl() != null)
? frame.getDocumentUrl()
: options.getBase();
// 10-11.
final ActiveContext activeContext =
new ActiveContext(input.getDocumentUrl(), input.getDocumentUrl(), options)
.newContext()
.create(context, contextBase);
// 13.
String graphKey = activeContext.uriCompaction().vocab(true).compact(Keywords.GRAPH);
boolean frameDefault = false;
for (String key : frameObject.keySet()) {
if(key.equals(graphKey)) {
frameDefault = true;
break;
}
}
// 14.
final FramingState state = new FramingState();
state.setEmbed(options.getEmbed()); // 14.1.
state.setEmbedded(false); // 14.2.
state.setExplicitInclusion(options.isExplicit()); // 14.3.
state.setRequireAll(options.isRequiredAll()); // 14.4.
state.setOmitDefault(options.isOmitDefault()); // 14.5.
state.setGraphMap(NodeMapBuilder.with(expandedInput, new NodeMap()).build()); // 14.7.
if (frameDefault) {
state.setGraphName(Keywords.DEFAULT); // 14.6.
} else {
state.setGraphName(Keywords.MERGED);
state.getGraphMap().merge();
}
// 15.
final JsonMapBuilder resultMap = JsonMapBuilder.create();
// 16.
Framing.with(state,
new ArrayList<>(state.getGraphMap().subjects(state.getGraphName())),
Frame.of(expandedFrame),
resultMap,
null
)
.ordered(options.isOrdered())
.frame();
Stream result = resultMap.valuesToArray().stream();
// 17. - remove blank @id
if (!activeContext.inMode(JsonLdVersion.V1_0)) {
final List remove = findBlankNodes(resultMap.valuesToArray());
if (!remove.isEmpty()) {
result = result.map(v -> FramingProcessor.removeBlankIdKey(v, remove));
}
}
// 18. - remove preserve
final JsonArrayBuilder filtered = JsonProvider.instance().createArrayBuilder();
result.map(FramingProcessor::removePreserve).forEach(filtered::add);
// 19.
JsonValue compactedResults = Compaction
.with(activeContext)
.compactArrays(options.isCompactArrays())
.ordered(options.isOrdered())
.compact(filtered.build());
// 19.1.
if (JsonUtils.isEmptyArray(compactedResults)) {
compactedResults = JsonValue.EMPTY_JSON_OBJECT;
// 19.2.
} else if (JsonUtils.isArray(compactedResults)) {
compactedResults = JsonProvider.instance().createObjectBuilder()
.add(graphKey, compactedResults).build();
}
// 20.
compactedResults = replaceNull(compactedResults);
final boolean omitGraph;
if (options.isOmitGraph() == null) {
omitGraph = activeContext.inMode(JsonLdVersion.V1_1);
} else {
omitGraph = options.isOmitGraph();
}
// 21.
if (!omitGraph && !compactedResults.asJsonObject().containsKey(graphKey)) {
if (compactedResults.asJsonObject().isEmpty()) {
compactedResults = JsonProvider.instance().createObjectBuilder().add(graphKey,
JsonValue.EMPTY_JSON_ARRAY
).build();
} else {
compactedResults = JsonProvider.instance().createObjectBuilder().add(graphKey,
JsonProvider.instance().createArrayBuilder().add(compactedResults)
).build();
}
}
// 19.3.
if (!JsonUtils.isEmptyArray(context) && !JsonUtils.isEmptyObject(context)) {
compactedResults = JsonProvider.instance().createObjectBuilder(compactedResults.asJsonObject()).add(Keywords.CONTEXT, context).build();
}
return compactedResults.asJsonObject();
}
public static JsonObject frame(final URI input, final URI frame, final JsonLdOptions options) throws JsonLdError {
return frame(getDocument(input, options), getDocument(frame, options), options);
}
private static Document getDocument(final URI document, final JsonLdOptions options) throws JsonLdError {
if (options.getDocumentLoader() == null) {
throw new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Document loader is null. Cannot fetch [" + document + "].");
}
final DocumentLoaderOptions loaderOptions = new DocumentLoaderOptions();
loaderOptions.setExtractAllScripts(options.isExtractAllScripts());
final Document remoteDocument = options.getDocumentLoader().loadDocument(document, loaderOptions);
if (remoteDocument == null) {
throw new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED, "Cannot load document [" + document + "].");
}
return remoteDocument;
}
private static JsonValue removePreserve(JsonValue value) {
if (JsonUtils.isScalar(value)) {
return value;
}
if (JsonUtils.isArray(value)) {
final JsonArrayBuilder array = JsonProvider.instance().createArrayBuilder();
value.asJsonArray().forEach(item -> array.add(removePreserve(item)));
return array.build();
}
final JsonObjectBuilder object = JsonProvider.instance().createObjectBuilder();
for (final Entry entry : value.asJsonObject().entrySet()) {
if (Keywords.PRESERVE.equals(entry.getKey())) {
return entry.getValue().asJsonArray().get(0);
}
object.add(entry.getKey(), removePreserve(entry.getValue()));
}
return object.build();
}
private static JsonValue replaceNull(JsonValue value) {
if (JsonUtils.isString(value) && Keywords.NULL.equals(((JsonString)value).getString())) {
return JsonValue.NULL;
} else if (JsonUtils.isScalar(value)) {
return value;
} else if (JsonUtils.isArray(value)) {
final JsonArrayBuilder array = JsonProvider.instance().createArrayBuilder();
value.asJsonArray().forEach(item -> array.add(replaceNull(item)));
final JsonArray result = array.build();
return result.size() != 1 || JsonUtils.isNotNull(result.get(0)) ? result : JsonValue.EMPTY_JSON_ARRAY;
}
final JsonObjectBuilder object = JsonProvider.instance().createObjectBuilder();
value.asJsonObject().entrySet().forEach(entry -> object.add(entry.getKey(), replaceNull(entry.getValue())));
return object.build();
}
private static JsonValue removeBlankIdKey(JsonValue value, List blankNodes) {
if (JsonUtils.isScalar(value)) {
return value;
}
if (JsonUtils.isArray(value)) {
final JsonArrayBuilder array = JsonProvider.instance().createArrayBuilder();
value.asJsonArray().forEach(item -> array.add(removeBlankIdKey(item, blankNodes)));
return array.build();
}
final JsonObjectBuilder object = JsonProvider.instance().createObjectBuilder();
for (final Entry entry : value.asJsonObject().entrySet()) {
if (Keywords.ID.equals(entry.getKey())
&& JsonUtils.isString(entry.getValue())
&& blankNodes.contains(((JsonString)entry.getValue()).getString())) {
continue;
}
object.add(entry.getKey(), removeBlankIdKey(entry.getValue(), blankNodes));
}
return object.build();
}
private static List findBlankNodes(final JsonArray array) {
if(array.isEmpty()) {
return List.of();
}
Map candidates = new HashMap<>();
array.forEach(v -> findBlankNodes(v, candidates));
if(candidates.isEmpty()) {
return List.of();
}
return candidates.entrySet().stream().filter(e -> e.getValue() == 1).map(Entry::getKey).collect(Collectors.toList());
}
private static void findBlankNodes(JsonValue value, final Map blankNodes) {
if (JsonUtils.isString(value)) {
if (BlankNode.isWellFormed(((JsonString)value).getString())) {
Integer count = blankNodes.computeIfAbsent(((JsonString)value).getString(), x -> 0);
blankNodes.put(((JsonString)value).getString(), ++count);
}
return;
}
if (JsonUtils.isScalar(value)) {
return;
}
if (JsonUtils.isArray(value)) {
for (JsonValue item : value.asJsonArray()) {
findBlankNodes(item, blankNodes);
}
return;
}
for (Entry entry : value.asJsonObject().entrySet()) {
findBlankNodes(entry.getValue(), blankNodes);
}
}
}