2. Glossary¶

API¶: The Application Programming Interface is a collection of methods that a software program makes available to allow interaction with other programs.
Claim¶: In JSON Web Token, a claim is a piece of information about a subject, structured as a key/value pair.
CSV¶: CSV stands for Comma Separated Value, and is a file in which the content is organised in a fixed number of fields per line, separated by a comma (,) or some other symbol, like a semi-colon, a slash, or a vertical bar.
DAL¶: The DAL is used by the reader and writer to communicate with the database. See the detailed description.
Data Collector¶: A component of the Open Data Hub, a data collector is used to gather data from datasets and send them to the Open Data Hub. See the detailed description.
Data Consumers¶: Applications that use data received from the Web Services. See the detailed description.
Data Format¶: Data format is the way information is encoded and exchanged between applications.
Data Provider¶: A Data Provider is an entity that supplies data or datasets to the Open Data Hub. See how it is integrated in the Open Data Hub and a detailed description.
Database¶: Also known as persistence layer, the database (“DB”) stores all the data received by the writer. See the detailed description.
Dataset¶: A dataset is a collection of records from a Data source. See the detailed description.
Domain¶: A domain is a category of interest to which one or more datasets belong to.
DTO¶: A core component of the Open Data Hub, the DTO transforms the data format of a Source into a Open Data Hub-understandable format. See the detailed description.
Endpoint¶: An Endpoint is an online resource that make data available, usually through REST APIs.
JSON¶: The JavaScript Object Notation is a lightweight data format to ease the exchange of data between computer and its understanding for humans. Essentially a JSON file is a sequence of key-value pairs, organised into lists (arrays, sequences, vectors). Nesting of key-values and of lists is supported.
JSON Web Token¶: It is a mechanism to exchange a claim between two parties, used for authentication purposes when the claim is digitally signed and/or encrypted.
Key-value¶: Also called name-value pair or attribute-name pair, a key-value pair is a simple data structure in which information are stored as tuples {attribute, value}, with no constraint of uniqueness on both attribute and value.
ODHtags¶: In the tourism domain, this name refers to all the tags/filter that refer to data that have been validated by the Open Data Hub team.
Persistence Layer¶: Another name for Database, see the above entry or the detailed description.
Reader¶: A core component of the Open Data Hub, the Reader extract data form the Database and sends it to the web services. See the detailed description.
REST API¶
RESTful API¶: A REST(ful) API is a Web Service that adheres the architectural constraint of a RESTful system. It is composed of a URI, a collection of methods to interact with the resources offered by the Web Service, and a media type defining the accepted data formats.
Sensor¶: Within the Open Data Hub, a sensor is intended as a kind of device that gathers data and sends them to another device which stores them in a machine-readable format, used to exchange or publish them. Depending on the domain a sensor may collect environmental data in the mobility domain (like, e.g., temperature, humidity, pressure), but in the tourism domain a sensor can collect the guests in a hotel or the people attending at an event. In these cases, the device is usually a human (e.g., the hotel’s receptionist and the organiser of the event), and the data are digitalised manually.
Statistical Graphics¶: Statistical graphics are means to display statistical data with the purpose to ease their interpretations. Common statistical graphics include pie charts, histograms, and scatter plot.
Web Component¶: A Web Component is a set of API that allows the creation of interoperable HTML widgets that can be shared and reused.
Web Services¶: In the context of the Open Data Hub Project, web services expose to Data Consumers the data received from the reader. See the detailed description.
Writer¶: The Writer is a core component of the Open Data Hub. It receives data from the Data Collectors and stores them in the Database. See the detailed description.