sparqler
v0.8.0
Published
SPARQL query buildER for JavaScript/TypeScript
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SPARQLER
SPARQL query buildER for JavaScript/TypeScript.
SPARQLER offers a fluent interface to help you construct queries and prevent errors by malformed patterns.
Installation
With npm installed, run
npm install sparqler
Usage examples
import { SPARQLER } from "sparqler";
// const SPARQLER = require( "sparqler" ).SPARQLER // With Node.js
let query = new SPARQLER()
.base( "https://example.com/resource/" )
.prefix( "ex", "https://example.com/ns#" )
.select( _ => [
_.var( "bar" )
] )
.where( _ => [
_.resource( "" )
.has( _.resource( "ex:foo" ), _.var( "bar" ) )
.and( _.resource( "ex:baz" ), _.literal( 10 ) ),
] )
.orderBy( _ => [
_.desc( _.var( "bar" ) )
] )
.toPrettyString();
// .toCompactString(); // Minimal query size, but difficult to read
console.log( query );
Output:
BASE <https://example.com/resource/>
PREFIX ex: <https://example.com/ns#>
SELECT ?bar
WHERE {
<> ex:foo ?bar;
ex:baz 10
}
ORDER BY DESC (?bar)
Every method generates a different object with the corresponding methods available in that step. This means that, if you store a query reference and modify it afterwards, printing the reference will not have the modification. However, this also means that you can generate different queries using a shared base without mutating it:
import { SPARQLER } from "sparqler";
let query1 = new SPARQLER()
.base( "https://example.com/resource/" )
.prefix( "ex", "https://example.com/ns#" )
.select( _ => _.var( "bar" ) )
.where( _ => _.resource( "" ).has( _.resource( "ex:foo" ), _.var( "bar" ) ) );
// Add an order
let query2 = query1
.orderBy( _ => [
_.desc( _.var( "bar" ) )
] );
console.log( query1.toPrettyString() );
console.log( query2.toPrettyString() );
Output:
# query1
BASE <https://example.com/resource/>
PREFIX ex: <https://example.com/ns#>
SELECT ?bar
WHERE { <> ex:foo ?bar }
# query2
BASE <https://example.com/resource/>
PREFIX ex: <https://example.com/ns#>
SELECT ?bar
WHERE { <> ex:foo ?bar }
ORDER BY DESC (?bar) # The added order
API Documentation
See https://carbonldp.github.io/sparqler/ for the API documentation.
License
Copyright (c) 2015-present, Base22 Technology Group, LLC.
All rights reserved.
This source code is licensed under the BSD-style license found in the
LICENSE file in the root directory of this source tree.