main.js

const fs = require('fs');
const fastcsv = require('fast-csv');
const pdfjsLib = require('pdfjs-dist/es5/build/pdf.js');

function collapse(info, metadata, filename) {
  const result = {
    Title: filename || info.Title,
    Author: info.Author,
    Subject: info.Subject || '',
    PDFFormatVersion: info.PDFFormatVersion,
    CreationDate: metadata._metadataMap.get('xmp:createdate'),
    ModifiedDate: metadata._metadataMap.get('xmp:modifydate'),
    Creator: info.Creator,
    IsAcroFormPresent: info.IsAcroFormPresent,
    IsXFAPresent: info.IsXFAPresent,
    Contact: metadata['desc:contact'] || '',
  };
  return result;
}

function summarize(pdf, filename) {
  // Loading a document.
  var loadingTask = pdfjsLib.getDocument(pdf);
  return loadingTask.promise
    .then(async function (pdfDocument) {
      const {
        info,
        metadata,
        contentDispositionFilename,
      } = await pdfDocument.getMetadata();

      console.log(info);
      console.log(metadata);
      const output = collapse(info, metadata, filename);
      return output;
    })
    .catch(function (reason) {
      console.error('Error: ' + reason);
    });
}

async function getPDFInfo() {
  const pdfPath = 'data/pdf';
  const stat = fs.readdirSync(pdfPath);
  const output = [];
  for (const file of stat) {
    const filepath = `${pdfPath}/${file}`;
    let info = await summarize(filepath, file);
    output.push(info);
  }
  return output;
}

async function writePDFSummary(outputPath) {
  const data = await getPDFInfo();

  const ws = fs.createWriteStream('data/output.csv');
  fastcsv.write(data, { headers: true }).pipe(ws);
}

writePDFSummary('output.csv');