What is OpenCube Toolkit?
The OpenCube Toolkit is a set of integrated open source components available for free use. The tools are released as open source software components. To make easier the reuse of these components and building applications with their help, the open source Information Workbench Community Edition platform was used as an “architectural backbone” of the toolkit, providing the SDK for building customized applications and realizing generic low-level functionalities such as shared data access, logging and monitoring.
The OpenCube project in general and the component development effort in particular focus on processing of RDF data cubes: multi-dimensional data represented as RDF and structured according to the RDF Data Cube ontology. In the first project stage, the majority of the developed components were targeting the data reuse stage of the lifecycle and aimed more at end users rather than data administrators.
- TARQL extension for data cubes – data conversion to RDF from legacy tabular data, such as CSV/TSV files
- D2RQ extension for data cubes – data conversion from relational databases into RDF
- JSON-stat2qb extension for data cubes – data conversion from JSON-stat files into RDF
- R2RML extension for data cubes – data transformation of cubes structured in tabular sources to linked data cubes
OpenCube Compatibility Explorer – Given an initial cube in the local RDF store of the infrastructure, the main role of the Compatibility Explorer is to (a) search into the Linked Data Web and identify cubes that are compatible to expand the initial cube, and (b) establish typed links between the local cube and the compatible ones.
OpenCube Aggregator – the role of the Aggregator is twofold. First, given an initial cube with n dimensions the aggregator creates 2n−1 new cubes taking into account all the possible combinations of the n dimensions. Second, given an initial cube and a hierarchy of a dimension, the aggregator creates new observations for all the attributes of the hierarchy.
- OpenCube Expander – It creates a new expanded cube by merging two compatible cubes.
- Data catalogue management – user interface (UI) templates for managing metadata on RDF data cubes and supporting search and discovery
- OpenCube Browser – table-based visualizations of RDF data cubes
- OpenCube OLAP Browser – it enables performing OLAP operations (e.g. pivot, drill-down, and roll-up) on top of multiple linked data cubes.
- R statistical analysis – enables execution of R data analysis scripts from the OpenCube Toolkit, visualization of results or their integration as RDF triples.
- Interactive chart visualization widgets – visualization of the RDF data cube slices with charts
- OpenCube MapView – map-based visualizations of linked data cubes with a geo-spatial dimension. It enables performing OLAP operations.
To run the OpenCube Toolkit you need:
- a compatible version of the Java runtime (ideally, version 1.7).
- the OpenCube Toolkit distribution (.zip file).
To get started, proceed as follows:
- Unpack the OpenCube toolkit zip distribution.
- Open the terminal application and cd into the unpacked distribution (e.g. ‘cd Desktop/OCT’ [ENTER])
- In the file, ‘fiwb/iwb.sh’, modify the value for RUN_AS_USER=fluid to the user name that is intended to run the Information Workbench. (Alternatively, create a user account with the name ‘fluid’.)
- Start the OpenCube Toolkit
After a few seconds, you should be able to access the OpenCube Toolkit in you browser locally under the address http://localhost:8888
Once the OpenCube Toolkit is running (startup may take up to a few minutes), it can be accessed at https://localhost:8443 . On the default start page you can find a tutorial with some first steps as well as links to important pages (such as the detailed user documentation).
Download the latest version of the OpenCube Toolkit: