30 lines
1.1 KiB
JavaScript
30 lines
1.1 KiB
JavaScript
// **N3StreamWriter** serializes a quad stream into a text stream.
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import { Transform } from 'readable-stream';
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import N3Writer from './N3Writer';
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// ## Constructor
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export default class N3StreamWriter extends Transform {
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constructor(options) {
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super({ encoding: 'utf8', writableObjectMode: true });
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// Set up writer with a dummy stream object
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const writer = this._writer = new N3Writer({
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write: (quad, encoding, callback) => { this.push(quad); callback && callback(); },
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end: callback => { this.push(null); callback && callback(); },
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}, options);
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// Implement Transform methods on top of writer
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this._transform = (quad, encoding, done) => { writer.addQuad(quad, done); };
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this._flush = done => { writer.end(done); };
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}
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// ### Serializes a stream of quads
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import(stream) {
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stream.on('data', quad => { this.write(quad); });
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stream.on('end', () => { this.end(); });
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stream.on('error', error => { this.emit('error', error); });
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stream.on('prefix', (prefix, iri) => { this._writer.addPrefix(prefix, iri); });
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return this;
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}
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}
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