YARS-PG Property Graph to RDF* Processor.
YARS-PG reader for RDF.rb. Reads Property Graph descriptions and generates RDF* datasets.
Features
YARSPG parses CSV or other Tabular Data into RDF*.
- Nodes, properties, and string annotations are treated as document-relative fragments.
- Edges are emitted only to the default graph, with properties and annotations emitted either to the default graph, or the specifically named graph(s).
- Node labels are treated as as document-relative
rdf:type
values. - List complex values are emitted as
rdf:Lists
. - Set and Struct complex values are emitted as
rdf:JSON
literals.
Installation
Install with gem install yarspg
.
Description
YARSPG parses YARS-PG formatted documents into RDF* datasets, where edges are RDF triples in the default graph, which form the subject of the properties and annotations on that edge.
There is currently no extra support for Node Schemas or Edge Schemas.
Example
An example YARS-PG document follows:
# Prefix declaration
:foaf: <http://xmlns.com/foaf/0.1/>
%METADATA
-foaf:maker: "Łukasz Szeremeta and Dominik Tomaszuk"
%NODES
<"Author01">{"Author"}["fname": "John", "lname": "Smith"] #Author01
<"Author02">{"Author"}["fname": "Alice", "lname": "Brown"]
<"EI01">{"Entry", "InProceedings"}["title": "Serialization for...", "numpages": 10, "keyword": "Graph database"]
<"EA01">{"Entry", "Article"}["title": "Property Graph...", "numpages": 10, "keyword": ["Query", "Graph"]]
<"Proc01">{"Proceedings"}["title": "BDAS", "year": 2018, "month": "May"]
<"Jour01">{"Journal"}["title": "J. DB", "year": 2020, "vol": 30]
%EDGES
("EI01")-{"has_author"}["order": 1]->("Author01")
("EI01")-{"has_author"}["order": 2]->("Author02")
("EA01")-{"has_author"}["order": 1]->("Author02")
("EA01")-{"cites"}->("EI01")
("EI01")-{"booktitle"}["pages": "111-121"]->("Proc01")
("EA01")-{"published_in"}["pages": "222-232"]->("Jour01")
This results in the following TriG*:
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
<> foaf:maker "Łukasz Szeremeta and Dominik Tomaszuk" .
<#Author01> a <#Author>; <#fname> "John"; <#lname> "Smith" .
<#Author02> a <#Author>; <#fname> "Alice"; <#lname> "Brown" .
<#EI01> a <#Entry>, <#InProceedings>;
<#title> "Serialization for...";
<#numpages> 10;
<#keyword> "Graph database";
<#booktitle> <#Proc01>;
<#has_author> <#Author02>, <#Author01> .
<#EA01> a <#Entry>, <#Article>;
<#title> "Property Graph...";
<#numpages> 10;
<#keyword> ("Query" "Graph");
<#cites> <#EI01>;
<#has_author> <#Author02>;
<#published_in> <#Jour01> .
<#Proc01> a <#Proceedings>;
<#month> "May";
<#title> "BDAS";
<#year> 2018 .
<#Jour01> a <#Journal>;
<#title> "J. DB";
<#vol> 30;
<#year> 2020 .
<<<#EI01> <#has_author> <#Author01>>> <#order> 1 .
<<<#EI01> <#has_author> <#Author02>>> <#order> 2 .
<<<#EA01> <#has_author> <#Author02>>> <#order> 1 .
<<<#EI01> <#booktitle> <#Proc01>>> <#pages> "111-121" .
<<<#EA01> <#published_in> <#Jour01>>> <#pages> "222-232" .
RDF Reader
YARS acts as a normal RDF reader, using the standard RDF.rb Reader interface:
graph = RDF::Graph.load("etc/doap.yarspg")
alternatively
graph = RDF::Graph.new {|g| YARSPG::Reader.open("etc/doap.yarspg") {|r| g << r}}
Principal Classes
- {YARSPG}
- {YARSPG::Format}
- {YARSPG::Meta}
- {YARSPG::Reader}
- {YARSPG::Terminals}
Dependencies
Installation
The recommended installation method is via RubyGems.
To install the latest official release of the RDF::Tabular
gem, do:
% [sudo] gem install yarspg
Mailing List
Author
Contributing
- Do your best to adhere to the existing coding conventions and idioms.
- Don't use hard tabs, and don't leave trailing whitespace on any line.
- Do document every method you add using YARD annotations. Read the tutorial or just look at the existing code for examples.
- Don't touch the
rdf-tabular.gemspec
,VERSION
orAUTHORS
files. If you need to change them, do so on your private branch only. - Do feel free to add yourself to the
CREDITS
file and the corresponding list in the theREADME
. Alphabetical order applies. - Do note that in order for us to merge any non-trivial changes (as a rule of thumb, additions larger than about 15 lines of code), we need an explicit public domain dedication on record from you, which you will be asked to agree to on the first commit to a repo within the organization. Note that the agreement applies to all repos in the Ruby RDF organization.
License
This is free and unencumbered public domain software. For more information, see https://unlicense.org/ or the accompanying {file:UNLICENSE} file.