cayley-triple-io

Insert, Read and Delete triples from Cayley

Change Log

0.1.0

• First version.

Docs

Class: client

Creates a new Client instance

options: Object , Constructor options.

options.url: String , Cayley host url.

options.prefixes: Object , An object with RDF prefixes.

example

var tripleCrud = require('cayley-triple-io');
var client = new tripleCrud.Client({
    url: 'http://localhost:64210/',
    prefixes: {
        builder: 'http://service.jillix.com/jillix/service/app/builder/',
        schema: 'http://schema.org/',
        flow: 'http://schema.jillix.net/vocab/'
    }
});

client.createInsertStream(options, options.bufferSize)

Inserts triples into cayley

Parameters

options: Object, Object containing stream options.

options.bufferSize: Number, The number of triples that will be colected in the internal buffer before writing to cayley. Default is 10.

Returns: writable stream

Events

error - Will be called if an error is encountered while inserting the triple. Note the stream will not end if an error happens, all the triples written before and after the error will be inserted into cayley.

success - Will be called after all triples have been inserted.

example

var triples = [
    [
        'http://service.jillix.com/jillix/service/app/builder/someInstance',
        'http://schema.org/name',
        '"someInstance"'
    ],
    [
        'http://service.jillix.com/jillix/service/app/builder/someInstance',
        'http://schema.jillix.net/vocab/config',
        '_:bn1'
    ],
    [
        '_:bn1',
        'http://schema.org/name',
        '"someInstance"'
    ],
    [
        '_:bn1',
        'http://schema.org/age',
        '"22"^^http://www.w3.org/2001/XMLSchema#integer'
    ]
];

var stream = client.createInsertStream();

stream.on('error', function (err) {
    console.log(err);
});

stream.on('success', function () {
    console.log('Triples inserted.');
});

for (var i = 0; i < triples.length - 1; ++i) {
    stream.write(triples[i]);
}
stream.end(triples[triples.length - 1]);

client.createReadStream(query, options, options.deep, options.out)

reads triples from cayley

Parameters

query: Object, The cayley query that will be used to find the start node.

options: Object, Object containing stream options.

options.deep: Boolean, If false only the first level endges will be traversed. Default true.

options.out: Array, An array containing the predicates that will be traversed

Returns: readable stream

example

var stream = client.createReadStream(
    [
        'builder:someInstance',
    ]);

stream.on('error', function (err) {
    console.log(err);
});

stream.on('data', function (chunk) {
    console.log(chunk);
});

Query example

    [
        SOME_VALUE,
        ['In', 'SOME_PREDICATE'],
        ['Out', 'SOME_PREDICATE'],
        ['Is', 'SOME_VALUE'],
        ['Has', ['SOME_PREDICATE', 'SOME_VALUE']]
    ]

options example

    {
        deep: true,
        out: [
            'predicate_IRI',
            'prefix:predicate',
            ...
        ]
    }

*stream data example

[ 'http://service.jillix.com/jillix/service/app/builder/someInstance', 'http://schema.org/name', '"someInstance"' ]
[ 'http://service.jillix.com/jillix/service/app/builder/someInstance', 'http://schema.jillix.net/vocab/config', '_:bn1' ]
[ '_:bn1', 'http://schema.org/name', '"someInstance"' ]
[ '_:bn1', 'http://schema.org/age', '"22"^^http://www.w3.org/2001/XMLSchema#integer' ]

client.createDeleteStream(options, options.bufferSize)

deletes triples from cayley

Parameters

options: Object, Object containing stream options.

options.bufferSize: Number, The number of triples that will be colected in the internal buffer before deleting from cayley. Default is 10.

Returns: writable stream

Events

error - Will be called if an error is encountered while deleting the triple. Note the stream will not end if an error happens, all the triples written before and after the error will be deleted from cayley.

success - Will be called after all triples have been deleted.

example

var triples = [
    [
        'http://service.jillix.com/jillix/service/app/builder/someInstance',
        'http://schema.org/name',
        '"someInstance"'
    ],
    [
        'http://service.jillix.com/jillix/service/app/builder/someInstance',
        'http://schema.jillix.net/vocab/config',
        '_:bn1'
    ],
    [
        '_:bn1',
        'http://schema.org/name',
        '"someInstance"'
    ],
    [
        '_:bn1',
        'http://schema.org/age',
        '"22"^^http://www.w3.org/2001/XMLSchema#integer'
    ]
];

var stream = client.createDeleteStream();

stream.on('error', function (err) {
    console.log(err);
});

stream.on('success', function () {
    console.log('Triples deleted.');
});

for (var i = 0; i < triples.length - 1; ++i) {
    stream.write(triples[i]);
}
stream.end(triples[triples.length - 1]);

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