Creates a stream from PDF
Node.js module for streaming PDF text content.
Based on PDF.js library.
npm i pdf-stream --save
'use strict'; const text = require('pdf-stream').text; // Load file contents to ArrayBuffer synchronously let file = './example.pdf'; let pdf = new Uint8Array(fs.readFileSync(file)); // Stream PDF text to stdout text(pdf) .pipe(process.stdout);
You need the XMLHttpRequest as global variable.
Install the xhr2 library locally:
npm i xhr2 --save
'use strict'; const text = require('pdf-stream').text; global.XMLHttpRequest = require('xhr2'); // for PDFJS let pdf = 'https://mozilla.github.io/pdf.js/web/compressed.tracemonkey-pldi-09.pdf'; text(pdf) .pipe(process.stdout);
If you got error:
ReferenceError: DOMParser is not defined
You need the DOMParser as global variable, because PDF.js use it for XML metadata parsing. Install the xmldom library locally:
npm i xmldom --save
'use strict'; const text = require('pdf-stream').text; global.XMLHttpRequest = require('xhr2'); // File download global.DOMParser = require('xmldom').DOMParser; // XML Metadata parsing let pdf = 'https://mozilla.github.io/pdf.js/web/compressed.tracemonkey-pldi-09.pdf'; text(pdf) .pipe(process.stdout);
'use strict'; const Transform = require('stream').Transform; const pdf_stream = require('pdf-stream'); const PDFReadable = pdf_stream.PDFReadable; const PDFStringifyTransform = pdf_stream.PDFStringifyTransform; let url = 'https://mozilla.github.io/pdf.js/web/compressed.tracemonkey-pldi-09.pdf'; // Transform class for replacing strings class ReplaceTransform extends Transform { constructor(options) { super({ writableObjectMode: true, readableObjectMode: true }); this.from = options.from; this.to = options.to; } // For every object _transform(obj, encoding, cb) { // Get text content items if (typeof obj.textContent !== 'undefined' && Array.isArray(obj.textContent.items)) { obj.textContent.items.forEach((item, i) => { // Working with the PDF.js `textContent` object // Replace substring to another obj.textContent.items[i].str = item.str.replace(this.from, this.to); }); } this.push(obj); cb(); } } // Pipeline new PDFReadable(url) .pipe(new ReplaceTransform({ from: /trace/gi, to: ':-)' })) .pipe(new PDFStringifyTransform()) // Convert stream from object to string .pipe(process.stdout);
All methods are streams, use them with .pipe().
alternative usage:
text(pdf, whitespace)
Gets text stream from PDF.
Convert PDF to text, optionally can replace whitespaces.
Options:
pdf— URL or ArrayBuffer;whitespace— the string that replaces the whitespace␣. Replacement disabled by default.
In the PDF.js viewer whitespaces is an empty string. For making output comparable with the viewer use:
text(pdf, '')
Return: {stream.Readable}
alternative usage:
new PDFReadable(pdf)
Making the Readable stream in object mode from PDF text content.
Options:
pdf— URL or ArrayBuffer;- inherit from
stream.Readableoptions.
Return: {stream.Readable}
alternative usage:
new PDFStringifyTransform(whitespace)
Transform PDF text content object to string.
Options:
whitespace— the string that replaces the whitespace␣. Replacement disabled by default;- inherit from
stream.Transformoptions.
Return: {stream.Readable}
Contributors are welcome. Open an issue or submit pull request.
Small note: If editing the README, please conform to the standard-readme specification.
Apache 2.0
© Sergey N