npm-pdfreader VS polyfill

pdfreader is another tool that converts PDFs from binary to JSON format. Underneath, it uses pdf2json. Unlike the packages we have seen so far, which don't support tabular data, this package does so with automatic column detection and rule-based parsing.

import { PdfReader, TableParser } from "pdfreader"; const filename = "./uploads/table.pdf"; const nbCols = 2; const cellPadding = 40; const columnQuantitizer = (item) => parseFloat(item.x) >= 20; // polyfill for String.prototype.padEnd() // https://github.com/uxitten/polyfill/blob/master/string.polyfill.js // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/repeat if (!String.prototype.padEnd) { String.prototype.padEnd = function padEnd(targetLength, padString) { targetLength = targetLength >> 0; //floor if number or convert non-number to 0; padString = String(padString || " "); if (this.length > targetLength) { return String(this); } else { targetLength = targetLength - this.length; if (targetLength > padString.length) { padString += padString.repeat(targetLength / padString.length); //append to original to ensure we are longer than needed } return String(this) + padString.slice(0, targetLength); } }; } const padColumns = (array, nb) => Array.apply(null, { length: nb }).map((val, i) => array[i] || []); const mergeCells = (cells) => (cells || []).map((cell) => cell.text).join(""); const formatMergedCell = (mergedCell) => mergedCell.substr(0, cellPadding).padEnd(cellPadding, " "); const renderMatrix = (matrix) => (matrix || []) .map( (row, y) => "| " + padColumns(row, nbCols) .map(mergeCells) .map(formatMergedCell) .join(" | ") + " |" ) .join("\n"); var table = new TableParser(); new PdfReader().parseFileItems(filename, function (err, item) { if (err) console.error(err); else if (!item || item.page) { // end of file, or page console.log(renderMatrix(table.getMatrix())); item?.page && console.log("PAGE:", item.page); table = new TableParser(); // new/clear table for next page } else if (item.text) { // accumulate text items into rows object, per line table.processItem(item, columnQuantitizer(item)); } });