GraphQL + OWL: Mutations
In the fourth of our GraphQL + OWL series, we design the “write” side of the system: in GraphQL, Mutations. Mutations, as the name suggests, allow the manipulation of data.
GraphQL + OWL: Types & Fields
The third part of our “GraphQL + OWL” series deals with types and properties, which are the building blocks of ontology and GraphQL.
GraphQL + OWL: Namespaces
In this article, we begin the implementation of a system providing a GraphQL interface on top of an arbitrary set of ontologies.
Technical Leadership
The case study describes one of our core services; it shows how we organized the technical leadership in a project with a team of 25 people.
GraphQL + OWL: An “Ontologized” GraphQL Interface
This post describes a proposal for implementing a GraphQL interface over an arbitrary OWL. The article uses BIBFRAME as a reference ontology.
Spin Up An Apache Spark Cluster: Howto In 5 Minutes
This flash tip aims to provide the reader with the information required for spinning up an Apache Spark cluster
Spring Boot, GraphQL, TestContainers, PostgreSQL: Minimal Setup
This tip provides a minimalistic quickstart code for setting up a module using Spring Boot, GraphQL, PostgreSQL, and TestContainers.
Identity Management with Keycloak
In this article we’ll present what Keycloak can do and why it can be considered the Swiss army knife for almost any identity management needs.
GraphQL Custom Directives
Within this article we will explore how to implement custom GraphQL directives to protect content from exposure through your API.
Indexing At Scale
This case study describes the indexing pipeline we implemented for the Share-VDE project, a collaborative discovery environment that gathers data from several bibliographic institutions.
A GraphQL Mediator For Implementing A Hybrid Search API Layer
This article describes a design of a mediation layer that implements a hybrid search API through GraphQL.
GraphQL, REST: Take the Best of Both
Lessons learned, thoughts, about GraphQL and REST, the two most popular API paradigms
URIs 303 redirection for the Semantic Web
The Semantic Web was envisioned by Tim Berners-Lee as a Web made of data that machines could process.
In this article we are going to see how to use URI’s 303 Redirection to make resources available to machines and humans.
Spark SQL: Partitions and Sizes
Data fetching parallelisation in Apache Spark through Spark SQL / JDBC.
PartitionColumn, lowerBound, upperBound, numPartitions and a lot of other parameters: how do they work?
Apache Solr Atomic Updates: a Polymorphic Approach
In this post we describe an approach to solve the problem of an application that requires both Full and Atomic Updates, using one of the powerful concepts in Object Oriented Programming: Polymorphism.
Digging in the Solr code: 5 minutes howto
How to quickly debug a custom Apache Solr component (e.g. request handler, query parser, filter) in your favourite IDE.
The example uses IntelliJ but it is valid for any IDE.
Rated Ranking Evaluator: Help the poor (Search Engineer)
What is Search Quality? Why is it so important in a search infrastructure?
Do you need something that gives you the evidence about the direction the search system is going to? RRE is the tool you’re looking for.
Apache Solr: Orchestrating Known item and Full-text search
The Apache Solr Invisible Queries Request Handler
Apache Solr: Give the Height the Right Weight
Quantity detection? What is a quantity? And why do we need to detect it?
In this post we introduce a quantity detection plugin for Apache Solr.
Apache Solr: How To Implement a Search Workflow
In this post we describe an approach for orchestrating a search workflow in Apache Solr using Invisible Queries.
How to Implement a Search workflow in Apache Solr?
Towards a scalable Solr-based RDF Store
SolRDF (i.e., Solr + RDF) is a set of Solr extensions for managing (indexing and searching) RDF data. In a
RDF in Solr: HowTo
The Solr built-in UpdateRequestHandler supports several formats of input data. It delegates the actual data loading to a specific ContentStreamLoader, depending on the
Integration tests with jena-nosql and Cassandra
Integration tests with jena-nosql and Cassandra In this post I will illustrate the integration tests infrastructure I used for the
Apache Solr: “Exact Match” BATH compliant field
If you want to expose a Z3950 interface for an Information Retrieval sooner or later you will meet the BATH
Apache Qpid Committer!
It happened about a couple of months ago…I became an Apache Committer for Apache Qpid project (http://qpid.apache.org)! “Just a brief
IF-LESS code : (Yet Another Time) the State Pattern
State and Strategy Design Patterns in Action
