TIKA-4831: Add content-based detection and a parser for GeoGebra files (ggb, ggs, ggt)

[dschmidt]

Adds detection and parsing support for the GeoGebra file formats.

Issue: https://issues.apache.org/jira/browse/TIKA-4831

Detection

• application/vnd.geogebra.file (*.ggb) and application/vnd.geogebra.tool (*.ggt) are now sub-class-of application/zip, so the filename hint survives magic detection instead of being discarded in favor of plain application/zip
• new mime types: application/vnd.geogebra.slides (*.ggs, zip-based) and application/vnd.geogebra.pinboard (*.ggp, JSON-based)
• a new GeoGebraDetector (zip container detector, ZipFile and streaming mode) recognizes the formats without a filename by their well-known entries: geogebra.xml (worksheet), structure.json + _slideN/geogebra.xml (Notes/Slides), geogebra_macro.xml (tool). Since a worksheet with macros contains both geogebra.xml and geogebra_macro.xml, the decision is made after all entry names have been seen
• ZipParser.ZIP_SPECIALIZATIONS is kept in sync with the new registry entries

Parser

A new GeoGebraParser (miscoffice module) for ggb/ggs/ggt:

• metadata: construction title/author/date become dc:title/dc:creator/geogebra:date, plus geogebra:appName, geogebra:appVersion, geogebra:formatVersion, geogebra:id; Notes/Slides set xmpTPg:NPages
• content: user-visible text as XHTML paragraphs - string-literal expression elements of text objects, rich-text content runs (JSON), element captions, macro names and help texts; Notes/Slides emit one div per slide in structure.json order
• the representative rendering (geogebra_thumbnail.png at the root, or the first slide's thumbnail) is emitted as an embedded document marked embeddedResourceType=THUMBNAIL, following the existing convention in the OOXML, ODF and iWork parsers, so /unpack/all sidecars identify the preview image; other slides' thumbnails are redundant renderings and are skipped
• any other embedded file (e.g. inserted pictures) is emitted as an embedded document

XML is parsed through XMLReaderUtils.parseSAX like the other parsers in the module; structure.json and rich-text runs use Jackson (new jackson-databind dependency in the miscoffice module, version managed by the existing BOM import).

Testing

• new unit tests: GeoGebraDetectionTest (zip-commons) and GeoGebraParserTest (miscoffice) with crafted ggb/ggs/ggt fixtures; the ggs fixture deliberately orders _slide1 before _slide0 in structure.json to pin the ordering behavior
• full test suites of tika-core, tika-parser-zip-commons, tika-parser-miscoffice-module and tika-parser-pkg-module pass, plus CompositeZipContainerDetectorTest in the integration tests
• verified end-to-end against a real-world GeoGebra Notes file: detected as vnd.geogebra.slides, text extracted, thumbnail emitted with the THUMBNAIL marker

[Copilot]

Pull request overview

Adds first-class GeoGebra support to Apache Tika by introducing content-based detection for GeoGebra zip containers and a dedicated parser that extracts both metadata and user-visible text (plus a representative thumbnail as an embedded resource).

Changes:

• Added a GeoGebraDetector (zip-commons) to recognize ggb/ggs/ggt by zip entry names (including streaming detection).
• Added a GeoGebraParser + GeoGebraXMLHandler (miscoffice) to extract GeoGebra metadata/text and emit the thumbnail as an embedded document.
• Updated mime registry, zip specializations, module dependencies, and tests to cover new media types and parsing behavior.

Reviewed changes

Copilot reviewed 11 out of 17 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-zip-commons/src/test/java/org/apache/tika/detect/zip/GeoGebraDetectionTest.java	Adds detection tests for GeoGebra zip-based formats.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-zip-commons/src/main/resources/META-INF/services/org.apache.tika.detect.zip.ZipContainerDetector	Registers GeoGebraDetector via ServiceLoader.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-zip-commons/src/main/java/org/apache/tika/detect/zip/GeoGebraDetector.java	Implements content-based container detection for GeoGebra zip formats.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-pkg-module/src/main/java/org/apache/tika/parser/pkg/ZipParser.java	Adds GeoGebra media types to zip specialization set.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-miscoffice-module/src/test/java/org/apache/tika/parser/geogebra/GeoGebraParserTest.java	Adds parser tests for metadata, slide ordering, and thumbnail embedding behavior.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-miscoffice-module/src/main/java/org/apache/tika/parser/geogebra/GeoGebraXMLHandler.java	SAX handler for extracting metadata/text from GeoGebra XML + inline rich text JSON.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-miscoffice-module/src/main/java/org/apache/tika/parser/geogebra/GeoGebraParser.java	New parser for ggb/ggs/ggt, including embedded thumbnail + embedded resources.
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-miscoffice-module/pom.xml	Adds jackson-databind dependency for parsing structure.json and rich-text runs.
tika-core/src/test/java/org/apache/tika/TikaDetectionTest.java	Extends extension-based detection coverage for .ggp and .ggs.
tika-core/src/main/resources/org/apache/tika/mime/tika-mimetypes.xml	Adds .ggp mime type and marks GeoGebra zip-based types as sub-class-of application/zip.
CHANGES.txt	Documents new GeoGebra detection/parsing support (TIKA-4831).

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[Copilot]

Pull request overview

Copilot reviewed 11 out of 17 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 19 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 19 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 13 out of 19 changed files in this pull request and generated no new comments.

Suppressed comments (1)

Previously missed (1) — in code that hasn't changed since the last review.

tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-zip-commons/src/main/java/org/apache/tika/detect/zip/GeoGebraDetector.java:71

• In streaming detection mode, this detector always returns null from streamingDetectUpdate and waits for streamingDetectFinal to decide. Once both structure.json and a _slideN/geogebra.xml have been seen, the result is unambiguously GeoGebra Slides (GGS) and cannot be overturned by later entries, so returning GGS early would let DefaultZipContainerDetector/StreamingZipContainerDetector stop scanning the rest of a large ZIP.

    public MediaType streamingDetectUpdate(ZipArchiveEntry zae, InputStream zis,
                                           StreamingDetectContext detectContext) {
        Names names = detectContext.get(Names.class);
        if (names == null) {
            names = new Names();
            detectContext.set(Names.class, names);
        }
        names.update(zae.getName());
        return null;