TypeError: Cannot read property 'userAgent' of undefined error on node.js app run

Question

Hello I'm trying to get pdfreader module to work in node.js to convert PDFs into text format.

When I run it simply using command line like node sandbox/pdf.js (the contents below) it works fine.

var pdfreader = require('pdfreader');

var rows = {}; // indexed by y-position

function printRows() {
  Object.keys(rows) // => array of y-positions (type: float)
    .sort((y1, y2) => parseFloat(y1) - parseFloat(y2)) // sort float positions
    .forEach((y) => console.log((rows[y] || []).join('')));
}

new pdfreader.PdfReader().parseFileItems('lib/sandbox/book-eric.pdf', function(err, item){
  if (!item || item.page) {
    // end of file, or page
    printRows();
    console.log('PAGE:', item.page);
    rows = {}; // clear rows for next page
  }
  else if (item.text) {
    // accumulate text items into rows object, per line
    (rows[item.y] = rows[item.y] || []).push(item.text);
  }
});
`

When I launch it from my express-based node.js app, however, using node app I get the following error as soon as I include the module

var pdfreader = require('pdfreader');

The error is:

TypeError: Cannot read property 'userAgent' of undefined
    at detectSyncFontLoadingSupport (eval at <anonymous> (/Users/deemeetree/Documents/Root/InfraNodus/node_modules/pdf2json/lib/pdf.js:60:1), <anonymous>:42060:38)
    at eval (eval at <anonymous> (/Users/deemeetree/Documents/Root/InfraNodus/node_modules/pdf2json/lib/pdf.js:60:1), <anonymous>:42066:5)

It looks like the module that it's relying on, pdf2json is trying to get eval of some files and it's not working:

eval(_fileContent); which is the content of pdf2json files.

Anyone knows what I could do to make it work?

Answer 1

The solution was to add this before including the pdfreader module:

global.navigator = {
  userAgent: 'node',
}

window.navigator = {
  userAgent: 'node',
}

I hope it helps others as I spent 2 hours trying to troubleshoot it.