feat (core): Introduce XmlThingConverter

ToDo.yaml

@@ -20,6 +20,10 @@
 label: Enola.dev ToDo
 type: https://enola.dev/todo/List
 items:
+ - Update W3C Wiki with links to Enola docs:
+ links:
+ - https://www.w3.org/wiki/ConverterToRdf
+
  - Last `null` NPE, for Enola: &lastNPE
  links:
  - https://github.com/enola-dev/enola/issues/845

java/dev/enola/common/io/iri/URIs.java

@@ -66,6 +66,7 @@ public static MediaTypeAndOrCharset getMediaTypeAndCharset(URI uri) {
  var queryMap = getQueryMap(uri);
  var charsetParameter = queryMap.get(CHARSET);
  var mediaTypeParameter = queryMap.get(MEDIA_TYPE.toLowerCase());
+ if (mediaTypeParameter == null) mediaTypeParameter = queryMap.get(MEDIA_TYPE);
  return new MediaTypeAndOrCharset(mediaTypeParameter, charsetParameter);
  }
 

java/dev/enola/common/xml/BUILD

@@ -26,6 +26,7 @@ java_library(
  plugins = ["//tools/bazel/java_plugin:autoservice"],
  visibility = ["//:__subpackages__"],
  deps = [
+ "//java/dev/enola/common/convert",
  "//java/dev/enola/common/io",
  "@maven//:com_google_auto_service_auto_service_annotations",
  "@maven//:com_google_guava_guava",

java/dev/enola/common/xml/XML.java

@@ -57,6 +57,9 @@ public static void canonicalize(ReadableResource in, WritableResource out, boole
 
  private static String normalizeXML(InputStream inputStream, boolean format)
  throws ParserConfigurationException, IOException, SAXException, TransformerException {
+
+ // TODO Use streaming SAX instead of DOM; and break this up... use XmlResourceParser
+
  DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
  factory.setAttribute(XMLConstants.FEATURE_SECURE_PROCESSING, true); // #security
  DocumentBuilder builder = factory.newDocumentBuilder();

java/dev/enola/common/xml/XmlResourceParser.java

@@ -0,0 +1,51 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Copyright 2024 The Enola <https://enola.dev> Authors
+ *
+ * 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
+ *
+ * https://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 dev.enola.common.xml;
+
+import com.google.common.net.MediaType;
+
+import dev.enola.common.convert.CatchingConverterInto;
+import dev.enola.common.io.mediatype.MediaTypes;
+import dev.enola.common.io.resource.ReadableResource;
+
+import org.xml.sax.helpers.DefaultHandler;
+
+import javax.xml.parsers.SAXParser;
+import javax.xml.parsers.SAXParserFactory;
+
+public class XmlResourceParser implements CatchingConverterInto<ReadableResource, DefaultHandler> {
+
+ @Override
+ public boolean convertIntoThrows(ReadableResource from, DefaultHandler into) throws Exception {
+ if (!MediaTypes.normalizedNoParamsEquals(from.mediaType(), MediaType.XML_UTF_8))
+ return false;
+
+ if (from.byteSource().isEmpty()) return true;
+
+ SAXParserFactory factory = SAXParserFactory.newInstance();
+ factory.setNamespaceAware(true);
+ factory.setXIncludeAware(false);
+ factory.setValidating(false);
+ SAXParser saxParser = factory.newSAXParser();
+
+ try (var is = from.byteSource().openStream()) {
+ saxParser.parse(is, into);
+ }
+ return true;
+ }
+}

java/dev/enola/core/rosetta/Rosetta.java

@@ -104,7 +104,9 @@ public Rosetta(ResourceProvider rp, Loader loader) {
  new GraphvizResourceConverter(loader, new GraphvizGenerator(tmp)),
  new GexfResourceConverter(loader, new GexfGenerator(tmp)),
  new CharResourceConverter(),
- new IdempotentCopyingResourceNonConverter()));
+ new IdempotentCopyingResourceNonConverter()
+ // TODO XML... with XmlResourceParser & XMLToThingHandler
+ ));
  }
 
  @Override

java/dev/enola/data/Repository.java

@@ -18,6 +18,9 @@
 package dev.enola.data;
 
 import com.google.common.collect.Iterables;
+import com.google.common.collect.Streams;
+
+import java.util.stream.Stream;
 
 /**
  * Repository is a Provider which, in addition to being able to getting a single T given an IRI, can
@@ -40,6 +43,10 @@ public interface Repository<T> extends ProviderFromIRI<T> {
  * implementation?
  */
  default Iterable<T> list() {
- return Iterables.transform(listIRI(), iri -> get(iri));
+ return Iterables.transform(listIRI(), this::get);
+ }
+
+ default Stream<T> stream() {
+ return Streams.stream(listIRI()).map(this::get);
  }
 }

java/dev/enola/datatype/DatatypeRepository.java

@@ -70,7 +70,12 @@ public Iterable<String> listIRI() {
 
  @Override
  public @Nullable Datatype<?> get(String iri) {
- return TLC.get(DatatypeRepository.class).get(iri);
+ return TLC.optional(DatatypeRepository.class)
+ .orElseThrow(
+ () ->
+ new IllegalStateException(
+ "Need DatatypeRepository in TLC for: " + iri))
+ .get(iri);
  }
  };
 }

java/dev/enola/format/tika/BUILD

@@ -32,6 +32,7 @@ java_library(
  "//java/dev/enola/common",
  "//java/dev/enola/common/convert",
  "//java/dev/enola/common/io",
+ "//java/dev/enola/format/xml",
  "//java/dev/enola/thing:thing_java",
  "@maven//:com_google_auto_service_auto_service_annotations",
  "@maven//:com_google_errorprone_error_prone_annotations",

java/dev/enola/format/tika/TikaThingConverter.java

@@ -27,6 +27,7 @@
 import dev.enola.common.io.iri.namespace.NamespaceRepositoryEnolaDefaults;
 import dev.enola.common.io.resource.ReadableResource;
 import dev.enola.common.io.resource.ResourceProvider;
+import dev.enola.format.xml.XMLToThingHandler;
 import dev.enola.thing.Thing;
 import dev.enola.thing.io.UriIntoThingConverter;
 import dev.enola.thing.repo.ThingsBuilder;
@@ -36,6 +37,8 @@
 import org.apache.tika.parser.AutoDetectParser;
 import org.apache.tika.parser.ParseContext;
 import org.apache.tika.sax.BodyContentHandler;
+import org.apache.tika.sax.TeeContentHandler;
+import org.xml.sax.ContentHandler;
 import org.xml.sax.SAXException;
 
 import java.io.IOException;
@@ -69,19 +72,21 @@ public boolean convertInto(URI from, ThingsBuilder thingsBuilder)
  public boolean convertInto(ReadableResource resource, ThingsBuilder thingsBuilder)
  throws ConversionException, IOException {
  if (resource.byteSource().isEmpty()) return false;
+ var thingBuilder = thingsBuilder.getBuilder(resource.uri().toString());
 
+ var iri = resource.uri().toString();
  Writer sw = new StringBuilderWriter();
- BodyContentHandler handler = new BodyContentHandler(sw);
+ var thingsHandler = new XMLToThingHandler(iri, thingBuilder);
+ ContentHandler handler = new TeeContentHandler(new BodyContentHandler(sw), thingsHandler);
 
  try (var is = resource.byteSource().openBufferedStream()) {
  Metadata metadata = new Metadata();
  ParseContext parseContext = new ParseContext();
  // TODO How to pass e.g. current Locale from TLC, e.g. for XLS parsing?
  parser.parse(is, handler, metadata, parseContext);
- var thing = thingsBuilder.getBuilder(resource.uri().toString());
- convertMetadata(metadata, thing);
+ convertMetadata(metadata, thingBuilder);
  var text = sw.toString().trim();
- if (!text.isEmpty()) thing.set("https://enola.dev/content-as-text", text);
+ if (!text.isEmpty()) thingBuilder.set("https://enola.dev/content-as-text", text);
  return true;
 
  } catch (TikaException | SAXException e) {

java/dev/enola/format/xml/BUILD

@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: Apache-2.0
+#
+# Copyright 2023 The Enola <https://enola.dev> Authors
+#
+# 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
+#
+# https://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.
+
+load("@rules_java//java:defs.bzl", "java_library")
+load("//tools/bazel:junit.bzl", "junit_tests")
+
+java_library(
+ name = "xml",
+ srcs = glob(
+ ["*.java"],
+ exclude = [
+ "*Test.java",
+ "Test*.java",
+ ],
+ ),
+ plugins = ["//tools/bazel/java_plugin:autoservice"],
+ resource_strip_prefix = "java/",
+ resources = glob(["**/*.html"]),
+ visibility = ["//:__subpackages__"],
+ deps = [
+ "//java/dev/enola/common/convert",
+ "//java/dev/enola/common/io",
+ "//java/dev/enola/common/xml",
+ "//java/dev/enola/thing:thing_java",
+ "@maven//:com_google_auto_service_auto_service_annotations",
+ "@maven//:com_google_errorprone_error_prone_annotations",
+ "@maven//:com_google_errorprone_error_prone_type_annotations",
+ "@maven//:com_google_guava_guava",
+ "@maven//:org_jspecify_jspecify",
+ "@maven//:org_slf4j_slf4j_api",
+ ],
+)
+
+junit_tests(
+ name = "tests",
+ srcs = glob([
+ "*Test.java",
+ ]),
+ deps = [
+ ":xml",
+ "//java/dev/enola/common/io",
+ "//java/dev/enola/thing:thing_java",
+ "//java/dev/enola/thing/testlib",
+ "//test",
+ ],
+)

java/dev/enola/format/xml/XMLToThingHandler.java

@@ -0,0 +1,135 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Copyright 2024 The Enola <https://enola.dev> Authors
+ *
+ * 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
+ *
+ * https://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 dev.enola.format.xml;
+
+import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableList;
+
+import dev.enola.common.io.iri.namespace.NamespaceRepository;
+import dev.enola.common.io.iri.namespace.NamespaceRepositoryBuilder;
+import dev.enola.thing.Thing;
+import dev.enola.thing.impl.IImmutablePredicatesObjects;
+import dev.enola.thing.impl.ImmutablePredicatesObjects;
+
+import org.jspecify.annotations.Nullable;
+import org.xml.sax.Attributes;
+import org.xml.sax.ContentHandler;
+import org.xml.sax.helpers.DefaultHandler;
+
+import java.util.ArrayDeque;
+import java.util.Deque;
+
+/**
+ * XML SAX {@link ContentHandler} which transforms XML into a {@link dev.enola.thing.Thing}.
+ *
+ * <p>This is NOT thread-safe!
+ */
+public class XMLToThingHandler extends DefaultHandler {
+
+ // TODO Consider implementing this via & through the existing JSON support instead?
+
+ private final String iri;
+ private final NamespaceRepositoryBuilder nrb = new NamespaceRepositoryBuilder();
+
+ private @Nullable String previousElementQName = null;
+ // TODO rm? private final
+ // List<List<IImmutablePredicatesObjects.Builder<IImmutablePredicatesObjects>>>
+ // builders = new ArrayList<>();
+ private final Deque<IImmutablePredicatesObjects.Builder<IImmutablePredicatesObjects>>
+ thingBuilders = new ArrayDeque<>();
+ private ImmutableList.@Nullable Builder<IImmutablePredicatesObjects> currentListBuilder;
+
+ @SuppressWarnings("unchecked")
+ public XMLToThingHandler(String iri, Thing.Builder<?> thingBuilder) {
+ this(iri, (IImmutablePredicatesObjects.Builder<IImmutablePredicatesObjects>) thingBuilder);
+ }
+
+ public XMLToThingHandler(
+ String iri,
+ IImmutablePredicatesObjects.Builder<IImmutablePredicatesObjects> thingBuilder) {
+ thingBuilders.push(thingBuilder);
+ this.iri = iri;
+ }
+
+ public NamespaceRepository getNamespaces() {
+ return nrb.build();
+ }
+
+ @Override
+ public void startPrefixMapping(String prefix, String uri) {
+ nrb.store(prefix, uri);
+ }
+
+ @Override
+ public void endPrefixMapping(String prefix) {
+ // Ignore.
+ }
+
+ private String iri(String uri, String localName, String qName) {
+ if (Strings.isNullOrEmpty(uri)) uri = iri;
+ if (Strings.isNullOrEmpty(localName)) throw new IllegalStateException(uri + " " + qName);
+ return uri + "/" + localName;
+ }
+
+ @Override
+ public void startElement(String uri, String localName, String qName, Attributes attributes) {
+ // TODO Remove this System.out.println again later!
+ System.out.println(
+ "startElement: uri=" + uri + ", localName=" + localName + ", qName=" + qName);
+ if (Strings.isNullOrEmpty(qName)) throw new IllegalStateException(localName);
+ if (!qName.equals(previousElementQName)) {
+ // Nested element
+ currentListBuilder = ImmutableList.builder();
+ } else {
+ // Same level element
+ }
+ previousElementQName = qName;
+
+ var nested = ImmutablePredicatesObjects.builder();
+ thingBuilders.add(nested);
+
+ // TODO Attributes, with #!
+ }
+
+ @Override
+ public void endElement(String uri, String localName, String qName) {
+ // TODO Remove this System.out.println again later!
+ System.out.println(
+ "endElement: uri=" + uri + ", localName=" + localName + ", qName=" + qName);
+ if (Strings.isNullOrEmpty(qName)) throw new IllegalStateException(localName);
+ if (!qName.equals(previousElementQName)) {
+ // Nested element
+ if (currentListBuilder == null) throw new IllegalStateException();
+ currentListBuilder.add(thingBuilders.removeLast().build());
+ var list = currentListBuilder.build();
+ // TODO rm? builders.peek().set(iri(uri, localName, qName), list);
+ var nested = thingBuilders.removeLast().set(iri(uri, localName, qName), list);
+ thingBuilders.peek().set(iri(uri, localName, qName), nested.build());
+ currentListBuilder = null;
+
+ } else {
+ // Same level element
+ // NOOP.
+ }
+ }
+
+ @Override
+ public void characters(char[] ch, int start, int length) {
+ // TODO set https://enola.dev/content-as-text ?
+ }
+}