Module resource

RFC 3987 resource identifiers.

Provides types and functions for validating resource identifiers (IRIs), checking nesting relationships and navigating identifier hierarchies, resolving and rewriting references, creating and inspecting namespace objects, and minting IRIs for local resources through the predefined base namespace. Prefix lexicons compact IRIs to the prefixed names used in SPARQL and Turtle text, and expand those names back to full IRIs.

Type Guards

import { isIRI } from "@metreeca/core/resource";

const value = "http://example.org/resource";

if (isIRI(value)) {
  // value is typed as IRI
}

// Variant-specific checks

isIRI("http://example.org/resource", "absolute");   // true
isIRI("/resource", "internal");                     // true
isIRI("../resource", "relative");                   // true
isIRI("http://example.org/资源", "absolute");        // true (Unicode allowed)
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Nesting Checks

import { isNestedIRI } from "@metreeca/core/resource";

isNestedIRI("http://example.com/a/", "http://example.com/a/b");   // true
isNestedIRI("http://example.com/a/", "http://example.com/a/");    // true (self-nesting)
isNestedIRI("http://example.com/a/", "http://example.com/x/y");   // false
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Reference Operations

import { getIRIBase, getIRIParent, internalize, relativize, resolve } from "@metreeca/core/resource";

const iri = "http://example.com/a/b/c";

// Resolve relative references against base

resolve(iri, "../d");                        // "http://example.com/a/d"
resolve(iri, "/d");                          // "http://example.com/d"

// Convert absolute to root-relative (internal) path

internalize(iri, "http://example.com/x/y");  // "/x/y"

// Convert absolute to relative path

relativize(iri, "http://example.com/a/d");   // "../d"

// Extract the base identifier usable for reference resolution

getIRIBase(iri);                             // "http://example.com/"
getIRIBase("/a/b");                          // undefined

// Extract the identifier of the enclosing collection

getIRIParent(iri);                           // "http://example.com/a/b/"
getIRIParent("/a/b/");                       // "/a/"
getIRIParent("a");                           // "./"
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Namespace Objects

import { base, createNamespace, getNamespaceBase, getNamespaceIRI } from "@metreeca/core/resource";

// Closed namespace with predefined terms

const rdfs = createNamespace("http://www.w3.org/2000/01/rdf-schema#", [
  "label",
  "comment"
]);

rdfs[""];           // IRI: "http://www.w3.org/2000/01/rdf-schema#"
rdfs.label;         // IRI: "http://www.w3.org/2000/01/rdf-schema#label"
rdfs["comment"];    // IRI: "http://www.w3.org/2000/01/rdf-schema#comment"
rdfs["seeAlso"];    // throws RangeError: unknown term

// Namespace accessors

getNamespaceIRI(rdfs);   // IRI: "http://www.w3.org/2000/01/rdf-schema#"
getNamespaceBase(rdfs);  // IRI: "http://www.w3.org/"

// Open namespace for dynamic terms

const ex = createNamespace("http://example.org/");

ex[""];             // IRI: "http://example.org/"
ex["anything"];     // IRI: "http://example.org/anything"

// Predefined open namespace for local resources

base[""];           // IRI: "base:/#"
base.label;         // IRI: "base:/#label"
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Compact URIs

import { compact, createLexicon, createNamespace, expand } from "@metreeca/core/resource";

const lexicon = createLexicon({
  rdfs: "http://www.w3.org/2000/01/rdf-schema#",
  ex: createNamespace("https://example.org/")
});

// Compact IRIs to prefixed names

compact(lexicon, "http://www.w3.org/2000/01/rdf-schema#label");  // "rdfs:label"
compact(lexicon, "https://example.com/Book");                    // undefined (undeclared namespace)

// Expand prefixed names to IRIs

expand(lexicon, "ex:Book");                                      // "https://example.org/Book"
expand(lexicon, "owl:Class");                                    // "owl:Class" (undeclared prefix)
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