neosemantics

##Installation

1. Build it

mvn clean package

2. Drop the jar in the <NEO_HOME>/plugins directory of your Neo4j instance.
3. Download additional jars to the plugins directory if needed.
4. Add the following line to your <NEO_HOME>/conf/neo4j.conf

dbms.unmanaged_extension_classes=semantics=/rdf

5. Restart the server.
6. Check that the installation went well by running call dbms.procedures(). The list of procedures should include the ones documented below. You can check that the extension is mounted by running :GET /rdf/ping

##What's in this repository This repository contains a set of stored procedures and extensions to both produce and consume RDF from Neo4j.

###Stored Procedures

Stored Proc Name	params	Description and example usage
semantics.importRDF	URL of the dataset serialization(*) shorten urls [true,false] convert types to labels periodic commit	Imports into Neo4j all the triples in the data set according to [the mapping defined in this post] (https://jesusbarrasa.wordpress.com/2016/06/07/importing-rdf-data-into-neo4j/). Note that before running the import procedure an index needs to be created on property uri of Resource nodes. Just run CREATE INDEX ON :Resource(uri) on your Neo4j DB. Examples: CALL semantics.importRDF("file:///.../myfile.ttl","Turtle", false, true, 9000) CALL semantics.importRDF("http:///.../data.rdf","RDF/XML", true, true, 9000)
semantics.previewRDF	URL of the dataset serialization(*) shorten urls [true,false] convert types to labels	Parses some RDF and produces a preview in Neo4j browser. Same parameters as data import except for periodic commit, since there is no data written to the DB. Notice that this is adequate for a preliminary visual analysis of a SMALL dataset. Think how many nodes you want rendered in your browser. Examples: CALL semantics.previewRDF("https://.../clapton.n3","Turtle", true, true)
semantics.previewRDFSnippet	An RDF snippet serialization(*) shorten urls [true,false] convert types to labels	Identical to previewRDF but takes an RDF snippet instead of the url of the dataset. Again, adequate for a preliminary visual analysis of a SMALL dataset. Think how many nodes you want rendered in your browser :) Examples: CALL semantics.previewRDFSnippet('[{"@id": "http://indiv#9132", "@type": ... }]', "JSON-LD", true, true)
semantics.LiteOntoImport	URL of the dataset serialization(*)	Imports the basic elements of an OWL or RDFS ontology, i.e. Classes, Properties, Domains, Ranges. Extended description here Example: CALL semantics.LiteOntoImport("http://.../myonto.trig","TriG")

(*) Valid formats: Turtle, N-Triples, JSON-LD, TriG, RDF/XML

###Extensions

Extension	params	Description and example usage
/rdf/describe/id	nodeid:the id of a node excludeContext:(optional) if present output will not include connected nodes, just selected one.	Produces an RDF serialization of the selected node. The format will be determined by the accept parameter in the header. Default is JSON-LD Example: :GET /rdf/describe/id?nodeid=0&excludeContext
/rdf/describe/uri	nodeuri:the uri of a node excludeContext:(optional) if present output will not include connected nodes, just selected one.	Produces an RDF serialization of the selected node. It works on a model either imported from an RDF dataset via semantics.importRDF or built in a way that nodes are labeled as :Resource and have an uri. This property is the one used by this extension to lookup a node. Example: :GET /rdf/describe/uri?nodeuri=http://dataset.com#id_1234
/rdf/cypher	Takes a cypher query in the payload	Produces an RDF serialization of the nodes and relationships returned by the query. Example: :POST /rdf/cypher "MATCH (a:Type1)-[r:REL]-(b) RETURN a, r, b"
/rdf/cypheronrdf	Takes a cypher query in the payload	Produces an RDF serialization of the nodes and relationships returned by the query. It works on a model either imported from an RDF dataset via semantics.importRDF or built in a way that nodes are labeled as :Resource and have an uri. Example: :POST /rdf/cypheronrdf "MATCH (a:Resource {uri:'http://dataset/indiv#153'})-[r]-(b) RETURN a, r, b"