RDF Explorer

RDF Explorer is a frontend for SPARQL endpoints that lets you explore resources and view their information, including attributes and relations.

DISCLAIMER: This is a work in progress. The application has been tested with Apache Jena Fuseki. Other SPARQL endpoints may not work properly. If you want extra features, please open read the contributing guidelines and open an issue.

Installation

To install RDF Explorer, you need to have Node.js and yarn and node installed. Once you have them installed, you can install all the dependencies by running the following command:

yarn install
yarn build
yarn start

Configuration

The application can be configured by using environment variables. The following variables are supported:

• PORT: The port where the application will be listening.
• LOGLEVEL: The log level. The possible values are DEBUG, INFO, WARN, and ERROR.
• SPARQL_QUERY_URL: The URL of the SPARQL endpoint to be used. A instance of RDF Explorer can only be used with one dataset. If you want to use RDF Explorer with multiple datasets, you need to run multiple instances of RDF Explorer.

You can use an .env file to set environment variables. For example, this command creates an .env file for our PROVENANCE endpoint:

$ echo 'SPARQL_QUERY_URL="https://endpoint.mint.isi.edu/provenance"
PORT=8000
LOGLEVEL=INFO' > .env

Usage

To get the information of a resource (for example, https://opmw.org/exportTest/resource/WorkflowExecutionAccount/Caesar_Cypher-2b-3c5e9dd8-6c44-4666-a6a2-cf572aca76db), you can use the following URL:

http://localhost:8000/opmw.org/exportTest/resource/WorkflowExecutionAccount/Caesar_Cypher-2b-3c5e9dd8-6c44-4666-a6a2-cf572aca76db

RDF Explorer will show the information of the resource, including its attributes and relations.

Content negotiation

RDF Explorer supports content negotiation. You can get the information of a resource in different formats by using the Accept header. For example, to get the information of https://opmw.org/exportTest/resource/WorkflowExecutionAccount/Caesar_Cypher-2b-3c5e9dd8-6c44-4666-a6a2-cf572aca76db in Turtle format, you can use the following command:

curl -H "Accept: text/turtle" http://localhost:8000/opmw.org/exportTest/resource/WorkflowExecutionAccount/Caesar_Cypher-2b-3c5e9dd8-6c44-4666-a6a2-cf572aca76db

The following formats are supported:

• text/turtle: Turtle format.
• application/rdf+xml: RDF/XML format.
• application/ld+json: JSON-LD format.
• application/n-triples: N-Triples format.
• application/n-quads: N-Quads format.
• application/trig: TriG format.
• application/n3: N3 format.
• text/n3: N3 format.
• text/html: HTML format.