bookexcerpt/excerpts.js

makes book excerpts, specify pdf as command line argument

// Dependencies
const pdf = require('pdfjs-dist');
const pdftk = require('node-pdftk');

// Source PDF and Watermark
var fullPdf = process.argv.slice(2)[0] + ""; // gets the pdf to be excerpted's filename
var markPdf = process.argv.slice(2)[1] + ""; // gets the watermark pdf

//  Reference a pdf document
pdf.getDocument(fullPdf).then(function (doc) {
  // Find Number of Pages
  var numPages = doc.numPages;
  var twntyPages = Math.round(numPages*.2); // find cutoff point

// Now use pdf toolkit to cat some Excerpts
  pdftk
    .input({
        A: fullPdf, // original pdf
        B: markPdf, // water mark
    })
    .cat('A1-1 B A2-'+twntyPages+' B') // 1st page pdf + mark + 2nd page - 20% of total Page Num + mark
    .output('./' + fullPdf.replace('.pdf','') + '_excerpt.pdf')
});

exports.printMsg = function() {
  console.log("Way to save some time!");
}