refactor: Simplify resource metadata generation

src/init/RootContainerInitializer.ts

@@ -1,4 +1,3 @@
-import { DataFactory } from 'n3';
 import { BasicRepresentation } from '../ldp/representation/BasicRepresentation';
 import { RepresentationMetadata } from '../ldp/representation/RepresentationMetadata';
 import type { ResourceIdentifier } from '../ldp/representation/ResourceIdentifier';
@@ -6,10 +5,9 @@ import { getLoggerFor } from '../logging/LogUtil';
 import type { ResourceStore } from '../storage/ResourceStore';
 import { TEXT_TURTLE } from '../util/ContentTypes';
 import { ensureTrailingSlash } from '../util/PathUtil';
-import { generateResourceQuads } from '../util/ResourceUtil';
+import { addResourceMetadata } from '../util/ResourceUtil';
 import { PIM, RDF } from '../util/Vocabularies';
 import { Initializer } from './Initializer';
-import namedNode = DataFactory.namedNode;
 
 /**
  * Initializes ResourceStores by creating a root container if it didn't exist yet.
@@ -43,7 +41,7 @@ export class RootContainerInitializer extends Initializer {
    */
   protected async createRootContainer(): Promise<void> {
     const metadata = new RepresentationMetadata(this.baseId, TEXT_TURTLE);
-    metadata.addQuads(generateResourceQuads(namedNode(this.baseId.path), true));
+    addResourceMetadata(metadata, true);
 
     // Make sure the root container is a pim:Storage
     // This prevents deletion of the root container as storage root containers can not be deleted

src/storage/DataAccessorBasedStore.ts

@@ -25,7 +25,7 @@ import {
   toCanonicalUriPath,
 } from '../util/PathUtil';
 import { parseQuads } from '../util/QuadUtil';
-import { generateResourceQuads } from '../util/ResourceUtil';
+import { addResourceMetadata } from '../util/ResourceUtil';
 import { CONTENT_TYPE, DC, HTTP, LDP, POSIX, PIM, RDF, VANN, XSD } from '../util/Vocabularies';
 import type { DataAccessor } from './accessors/DataAccessor';
 import type { ResourceStore } from './ResourceStore';
@@ -293,7 +293,7 @@ export class DataAccessorBasedStore implements ResourceStore {
     // Need to do this before handling container data to have the correct identifier
     const { metadata } = representation;
     metadata.identifier = DataFactory.namedNode(identifier.path);
-    metadata.addQuads(generateResourceQuads(metadata.identifier, isContainer));
+    addResourceMetadata(metadata, isContainer);
 
     // Validate container data
     if (isContainer) {

src/storage/accessors/FileDataAccessor.ts

@@ -1,8 +1,7 @@
 import type { Stats } from 'fs';
 import { createWriteStream, createReadStream, promises as fsPromises } from 'fs';
 import type { Readable } from 'stream';
-import { DataFactory } from 'n3';
+import type { Quad } from 'rdf-js';
-import type { NamedNode, Quad } from 'rdf-js';
 import type { Representation } from '../../ldp/representation/Representation';
 import { RepresentationMetadata } from '../../ldp/representation/RepresentationMetadata';
 import type { ResourceIdentifier } from '../../ldp/representation/ResourceIdentifier';
@@ -13,8 +12,8 @@ import { UnsupportedMediaTypeHttpError } from '../../util/errors/UnsupportedMedi
 import { guardStream } from '../../util/GuardedStream';
 import type { Guarded } from '../../util/GuardedStream';
 import { joinFilePath, isContainerIdentifier } from '../../util/PathUtil';
-import { parseQuads, pushQuad, serializeQuads } from '../../util/QuadUtil';
+import { parseQuads, serializeQuads } from '../../util/QuadUtil';
-import { generateResourceQuads } from '../../util/ResourceUtil';
+import { addResourceMetadata } from '../../util/ResourceUtil';
 import { toLiteral } from '../../util/TermUtil';
 import { CONTENT_TYPE, DC, LDP, POSIX, RDF, XSD } from '../../util/Vocabularies';
 import type { FileIdentifierMapper, ResourceLink } from '../mapping/FileIdentifierMapper';
@@ -251,8 +250,8 @@ export class FileDataAccessor implements DataAccessor {
   Promise<RepresentationMetadata> {
     const metadata = new RepresentationMetadata(link.identifier)
       .addQuads(await this.getRawMetadata(link.identifier));
-    metadata.addQuads(generateResourceQuads(metadata.identifier as NamedNode, isContainer));
+    addResourceMetadata(metadata, isContainer);
-    metadata.addQuads(this.generatePosixQuads(metadata.identifier as NamedNode, stats));
+    this.addPosixMetadata(metadata, stats);
     return metadata;
   }
 
@@ -306,30 +305,25 @@ export class FileDataAccessor implements DataAccessor {
         .mapFilePathToUrl(joinFilePath(link.filePath, childName), entry.isDirectory());
 
       // Generate metadata of this specific child
-      const subject = DataFactory.namedNode(childLink.identifier.path);
       const childStats = await fsPromises.lstat(joinFilePath(link.filePath, childName));
-      const quads: Quad[] = [];
+      const metadata = new RepresentationMetadata(childLink.identifier);
-      quads.push(...generateResourceQuads(subject, childStats.isDirectory()));
+      addResourceMetadata(metadata, childStats.isDirectory());
-      quads.push(...this.generatePosixQuads(subject, childStats));
+      this.addPosixMetadata(metadata, childStats);
-      yield new RepresentationMetadata(subject).addQuads(quads);
+      yield metadata;
     }
   }
 
   /**
    * Helper function to add file system related metadata.
-   * @param subject - Subject for the new quads.
+   * @param metadata - metadata object to add to
    * @param stats - Stats of the file/directory corresponding to the resource.
    */
-  private generatePosixQuads(subject: NamedNode, stats: Stats): Quad[] {
+  private addPosixMetadata(metadata: RepresentationMetadata, stats: Stats): void {
-    const quads: Quad[] = [];
+    metadata.add(DC.terms.modified, toLiteral(stats.mtime.toISOString(), XSD.terms.dateTime));
-    pushQuad(quads, subject, DC.terms.modified, toLiteral(stats.mtime.toISOString(), XSD.terms.dateTime));
+    metadata.add(POSIX.terms.mtime, toLiteral(Math.floor(stats.mtime.getTime() / 1000), XSD.terms.integer));
-    pushQuad(quads, subject, POSIX.terms.mtime, toLiteral(
-      Math.floor(stats.mtime.getTime() / 1000), XSD.terms.integer,
-    ));
     if (!stats.isDirectory()) {
-      pushQuad(quads, subject, POSIX.terms.size, toLiteral(stats.size, XSD.terms.integer));
+      metadata.add(POSIX.terms.size, toLiteral(stats.size, XSD.terms.integer));
     }
-    return quads;
   }
 
   /**

src/util/QuadUtil.ts

@@ -1,32 +1,12 @@
 import type { Readable } from 'stream';
 import arrayifyStream from 'arrayify-stream';
 import type { ParserOptions } from 'n3';
-import { DataFactory, StreamParser, StreamWriter } from 'n3';
+import { StreamParser, StreamWriter } from 'n3';
-import type { Literal, NamedNode, Quad } from 'rdf-js';
+import type { Quad } from 'rdf-js';
 import streamifyArray from 'streamify-array';
 import type { Guarded } from './GuardedStream';
 import { pipeSafely } from './StreamUtil';
-import { toSubjectTerm, toPredicateTerm, toObjectTerm } from './TermUtil';
 
-/**
- * Generates a quad with the given subject/predicate/object and pushes it to the given array.
- */
-export function pushQuad(
-  quads: Quad[] | Readable,
-  subject: string | NamedNode,
-  predicate: string | NamedNode,
-  object: string | NamedNode | Literal,
-): void {
-  quads.push(DataFactory.quad(toSubjectTerm(subject), toPredicateTerm(predicate), toObjectTerm(object)));
-}
-
-/**
- * Helper function for serializing an array of quads, with as result a Readable object.
- * @param quads - The array of quads.
- * @param contentType - The content-type to serialize to.
- *
- * @returns The Readable object.
- */
 export function serializeQuads(quads: Quad[], contentType?: string): Guarded<Readable> {
   return pipeSafely(streamifyArray(quads), new StreamWriter({ format: contentType }));
 }

src/util/ResourceUtil.ts

@@ -1,29 +1,24 @@
 import arrayifyStream from 'arrayify-stream';
-import type { NamedNode, Quad } from 'rdf-js';
 import { BasicRepresentation } from '../ldp/representation/BasicRepresentation';
 import type { Representation } from '../ldp/representation/Representation';
 import { RepresentationMetadata } from '../ldp/representation/RepresentationMetadata';
-import { pushQuad } from './QuadUtil';
 import { guardedStreamFrom } from './StreamUtil';
 
 import { LDP, RDF } from './Vocabularies';
 
 /**
  * Helper function to generate type quads for a Container or Resource.
- * @param subject - Subject for the new quads.
+ * @param metadata - Metadata to add to.
  * @param isContainer - If the identifier corresponds to a container.
  *
  * @returns The generated quads.
  */
-export function generateResourceQuads(subject: NamedNode, isContainer: boolean): Quad[] {
+export function addResourceMetadata(metadata: RepresentationMetadata, isContainer: boolean): void {
-  const quads: Quad[] = [];
   if (isContainer) {
-    pushQuad(quads, subject, RDF.terms.type, LDP.terms.Container);
+    metadata.add(RDF.terms.type, LDP.terms.Container);
-    pushQuad(quads, subject, RDF.terms.type, LDP.terms.BasicContainer);
+    metadata.add(RDF.terms.type, LDP.terms.BasicContainer);
   }
-  pushQuad(quads, subject, RDF.terms.type, LDP.terms.Resource);
+  metadata.add(RDF.terms.type, LDP.terms.Resource);
-
-  return quads;
 }
 
 /**

test/unit/util/QuadUtil.test.ts

@@ -1,28 +1,9 @@
 import 'jest-rdf';
 import { literal, namedNode, quad } from '@rdfjs/data-model';
-import type { Quad } from 'rdf-js';
+import { parseQuads, serializeQuads } from '../../../src/util/QuadUtil';
-import { parseQuads, pushQuad, serializeQuads } from '../../../src/util/QuadUtil';
 import { guardedStreamFrom, readableToString } from '../../../src/util/StreamUtil';
 
 describe('QuadUtil', (): void => {
-  describe('#pushQuad', (): void => {
-    it('creates a quad and adds it to the given array.', async(): Promise<void> => {
-      const quads: Quad[] = [];
-      pushQuad(quads, namedNode('sub'), namedNode('pred'), literal('obj'));
-      expect(quads).toEqualRdfQuadArray([
-        quad(namedNode('sub'), namedNode('pred'), literal('obj')),
-      ]);
-    });
-
-    it('creates a quad from strings and adds it to the given array.', async(): Promise<void> => {
-      const quads: Quad[] = [];
-      pushQuad(quads, 'sub', 'pred', 'obj');
-      expect(quads).toEqualRdfQuadArray([
-        quad(namedNode('sub'), namedNode('pred'), namedNode('obj')),
-      ]);
-    });
-  });
-
   describe('#serializeQuads', (): void => {
     it('converts quads to the requested format.', async(): Promise<void> => {
       const quads = [ quad(