Dockette / Tika

🎁 Apache Tika server with OCR on and extra Tesseract languages.

🕹 f3l1x.io | 💻 f3l1x | 🐦 @xf3l1x

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Apache Tika server that extracts text and metadata from PDF, Office, images and 1000+ other formats. The upstream apache/tika:<version>-full image has only 7 OCR languages and does not OCR scanned PDFs. This image adds 20 languages and turns OCR on.

Features

• Apache Tika 3.3.1.0 on the upstream -full image (Tesseract 5, GDAL, ImageMagick)
• 20 Tesseract languages and osd, see the table below
• OCR on by default, tuned for scanned PDFs (tika-config.xml)
• Prometheus JVM metrics on :9464/metrics (jmx_exporter 1.7.0)
• Healthcheck on /version
• Entrypoint, user 35002:35002 and port 9998 are the same as upstream

Code	Language	Code	Language
ara	Arabic	jpn	Japanese
ces	Czech	kor	Korean
chi_sim	Chinese simplified	nld	Dutch
chi_tra	Chinese traditional	pol	Polish
deu	German	por	Portuguese
eng	English	rus	Russian
fra	French	slk	Slovak
hin	Hindi	spa	Spanish
hun	Hungarian	tur	Turkish
ita	Italian	ukr	Ukrainian

Usage

docker run --rm -it -p 9998:9998 -p 9464:9464 dockette/tika:latest

# Text
curl -T document.pdf -H 'Accept: text/plain' http://localhost:9998/tika

# OCR in another language (default is eng), or in more languages
curl -T scan.pdf -H 'Accept: text/plain' -H 'X-Tika-OCRLanguage: slk' http://localhost:9998/tika
curl -T scan.pdf -H 'Accept: text/plain' -H 'X-Tika-OCRLanguage: eng+ces' http://localhost:9998/tika

# OCR every page, also when the PDF has a text layer
curl -T doc.pdf -H 'Accept: text/plain' -H 'X-Tika-PDFocrStrategy: ocr_and_text_extraction' http://localhost:9998/tika

# Text and metadata of every embedded document, as JSON
curl -T archive.zip http://localhost:9998/rmeta/text

Configuration

The image runs with tika-config.xml:

• ocrStrategy=auto: read the text layer, OCR only pages without text
• ocrDPI=250: measured on scanned invoices; the Tika default 300 gave worse results
• extractInlineImages=false: true OCRs each page twice and duplicates the text
• language=eng, pageSegMode=1, timeoutSeconds=300

To use your own file, mount it. Copy the <server> block from ours to keep the metrics.

docker run --rm -it -p 9998:9998 -v $(pwd)/tika-config.xml:/tika-config.xml:ro dockette/tika:latest

Arguments after the image name replace the default --config /tika-config.xml and go to TikaServerCli -h 0.0.0.0.

Set the heap in forkedJvmArgs, for example <arg>-Xmx4g</arg>. Without it, the JVM sizes the heap from host RAM. Do not use JAVA_TOOL_OPTIONS: it applies to both JVMs.

Metrics

Tika parses in a child JVM (TikaServerProcess). The child loads the jmx_exporter agent and serves jvm_* and process_* metrics on port 9464. Tika has no metrics of its own, so there are no per-request metrics. When the child restarts (OOM or timeout), process_start_time_seconds changes.

Versions

Version	Release
dockette/tika:3.3.1.0-YYYY.MM.DD	release YYYY.MM.DD
dockette/tika:3.3.1.0	latest release
dockette/tika:YYYY.MM.DD	release YYYY.MM.DD
dockette/tika:latest	latest build of master

All versions build on apache/tika:3.3.1.0-full. Releases are listed on GitHub.

Development

make build          # build the image
make test           # check languages and config
make test-docker    # start the server and OCR a scanned PDF
make run            # run the server on port 19998
make shell          # open a shell in the image
make push           # build and push linux/amd64 and linux/arm64
make version        # print VERSION
make release        # set today's date in VERSION

Maintenance

See how to contribute to this package. Consider to support f3l1x. Thank you for using this package.