GATE and Firefox plugins for S4


The Self-Service Semantic Suite (S4) by Ontotext provides a set of capabilities for on-demand, as-a-service semantic data management. The S4 capabilities are accessible via simple RESTful APIs, including APIs for text analytics and Linked Data access. In the near future, S4 will also provide a fully managed RDF database-as-a-service running in the cloud and accessible via RESTful services.

Even though working with RESTful APIs is easy and straightforward, the S4 team has put extra effort into making things even simpler for developers by providing a Java API as well as various code samples for using S4 services from Java, C#, Python, NodeJS, Groovy and PHP.

In the last week, the S4 team delivered two more plugins which will make developing S4 applications even easier: a brand new GATE plugin and a Firefox add-on.

Using S4 Text Analytics with GATE

The General Architecture for Text Engineering (GATE) is one of the most popular open source platforms for developing Natural Language Processing applications or language resources.  GATE comes with an extensive set of adapters for reading from and writing to various document formats, and components for various text analytics tasks. The text analytics components vary from low level ones — such as tokenisation, part-of-speech tagging and simple pattern matching — to more complex ones such as Named Entity Recognition (NER), coreference resolution and complex rule matching.

GATE also provides a powerful mechanism for supporting third-party extensions, so that new text processing components can  easily be added to GATE workflows and embedded into text analytics applications.

The GATE plugin for S4 is one such extension and provides easy access to the S4 text analytics services directly from the GATE platform. The S4 plug-in is implemented as a GATE Processing Resource (PR) and acts as a local proxy to RESTful services of S4. The PR can be integrated in any GATE processing pipeline regardless of the context and it does not have any requirements or assumptions about the type of pre-processing or post-processing of the textual data being annotated.

The documentation for the GATE plugin provides details on installing and configuring the plugin via the GATE plugin manager. The source code for the GATE plugin for S4 is also available from the S4 GitHub repository.

After the plugin is installed and configured it can be easily added to GATE pipelines for document processing. The following screenshots show the results of annotating news and bio-medical documents via S4 directly from the GATE environment:


Screenshot 2014-09-24 15.51.05

Firefox Add-on for S4

The Mozilla Firefox add-on for S4 provides an easy way of using the S4 text analytics services directly within the Firefox browser. The add-on can be installed from the Mozilla Marketplace at The source code for the add-on is also available from the S4 GitHub repository.


After installing the plugin, the user should configure it by specifying the private API key/secret pair and the specific S4 text analytics service to be used for annotation. The following screenshots show the results of annotating news and bio-medical documents via S4 directly from the Firefox browser:


Screenshot from 2014-09-24 15_36_11

Next Steps

The GATE plugin and Firefox add-on for S4 provide an easy way for developers and language engineers to test the S4 text analytics results directly from the GATE environment or Firefox browser. If you haven’t done so already – register for an S4 developer account, download the GATE plugin and the Firefox add-on and start using S4 text analytics right away!

  • Radu

    I have tried s4 Firefox plugin. Seems to work for news… However the colors are ugly … is there are a way to change them – apply a different style theme?


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