Getting started as a contributor

HeFQUIN is an open-source project focused on enabling efficient querying over heterogeneous data sources. Developers and users are encouraged to contribute to the project, whether by adding creating new extensions, suggesting new features, fixing bugs, or improving documentation.

Please read on if you're interested in contributing!

Set up your programming environment

Here's what you have to do to set up your programming environment to work on HeFQUIN.

Start by creating a local clone of the HeFQUIN repo using SSH:

git clone git@github.com:LiUSemWeb/HeFQUIN.git

git clone https://github.com/LiUSemWeb/HeFQUIN.git

Import the project into your favorite IDE

• Eclipse IDE
  1. Start Eclipse and create a new workspace.
  2. In the File menu, select Import....
  3. In the Import dialog that pops up, select as import source Maven->Existing Maven Projects.
  4. An Import Maven Projects dialog pops up. Click on the button Browse... (next to the Root Directory text field).
  5. In the file dialog that pops up now, navigate to the folder into which you have cloned the HeFQUIN git repo and click OK.
  6. Now, back in the Import Maven Projects dialog, the file pom.xml should be selected. Click on Finish.
  7. If you are still in the Welcome screen of Eclipse, click on Go to Workbench.

  You should now see HeFQUIN as a project in the Project Explorer window.

• Visual Studio Code
  1. Start Visual Studio Code.
  2. From the file dialog, open the folder into which you cloned the HeFQUIN git repo. Visual Studio Code should automatically configure the Maven project.

  You should now see HeFQUIN as a project in the Explorer window.

Build HeFQUIN using Maven

The HeFQUIN source code is a Maven project. Hence, instead of using Eclipse (or any other IDE for Java), you can also compile and build the project using Maven on the command line. To do this, enter the directory into which you have cloned the HeFQUIN git repo. Next, build the project using the following command:

mvn package

Assuming the build process completes without errors, you can now directly run the scripts in the bin/ directory:

1. hefquin - Run a single query via the engine. E.g.:

   
       ./bin/hefquin \
           --query ../ExampleQuery.rq \
           --federationDescription ../ExampleFederation.ttl 

2. hefquin-server - Start the engine as a service in an embedded web server (http://localhost:8080/). E.g.:

   ./bin/hefquin-server

3. hefquin-pg - Run a SPARQL query over a PG store. E.g.:

   
       ./bin/hefquin-pg \
           --query ExampleBGP.rq \
           --lpg2rdfconf ExampleLPG2RDF.ttl \
           --endpoint http://localhost:7474/db/neo4j/tx \
           --username neo4j-username \
           --password neo4j-password
                           

4. hefquin-pg - Materialize an RDF view of a PG store. E.g.:

   
       ./bin/hefquin-pgmat \
           --endpoint http://localhost:7474/db/neo4j/tx \
           --username neo4j-username \
           --password neo4j-password
                           

To see the list of other possible arguments for the command line tools, you may execute the script using the --help argument. E.g.:

./bin/hefquin --help