RDF source
The RDF data source is able to read RDF data
in N-Triples, Turtle, N3 or RDF/XML format and turn this into entities.
See the Working with RDF document for more detail on working with RDF in Sesam.
It will transform triples on the form <subject-uri> <predicate-uri> "value" OR <object-uri> into
entities on the form:
{
"_id": "<subject-uri>",
"<predicate-uri>": "value" OR "~robject-uri"
}
RDF Blank Nodes (aka BNodes) will be turned into child entities.
Prototype
{
"type": "rdf",
"system": "url--or-microservice-system-id",
"url": "url-to-rdf-file",
"sort_lists": true,
"format": "nt-ttl-or-xml"
}
Properties
Property |
Type |
Description |
Default |
Req |
|---|
system
|
String |
The ID of the URL system or microservice system component to use. |
|
Yes |
url
|
String |
The URL of the RDF file to load - it can contain multiple subjects
(with blank node hierarchies) and each unique non-blank subject will
result in a single root entity. |
|
Yes |
format
|
String |
The type of RDF file referenced by the url property. It is
an enumeration that can take following recognized values: "nt" for
N-Triples, "ttl" for Turtle, "n3" for N3 or "xml" for RDF/XML files. |
“nt” |
|
sort_lists
|
Boolean |
If the sort_lists is set to true any resulting entity properties containing lists of values (due to
them having the same RDF predicate) will be sorted, making the output predictable. This applies in a recursive
fashion. |
true |
|
is_sorted
|
Boolean |
Indicates that the input data is sorted on RDF subject. If the is_sorted is set to true and the
format property is nt (N-Triples), the RDF source will attempt to parse the input data sequentially and
emit a new entity when the RDF subject changes, without loading the entire RDF file into memory first.
Note that the input data cannot contain RDF Blank Nodes (aka
BNodes) in this case. The property has no effect on formats other than nt. |
false |
|
Continuation support
See the section on continuation support for more information.
Property |
Value |
|---|
supports_since
|
false (Default)
|
is_since_comparable
|
true (Default)
|
is_chronological
|
false (Default)
|
Example configuration
The outermost object would be your pipe configuration, which is omitted here for brevity:
{
"source": {
"type": "rdf",
"url": "http://www.snee.com/rdf/elvisimp.rdf",
"format": "xml",
}
}