node-qpdf

node-qpdf

A very simple wrapper for qpdf which is a content-preserving transformations on PDF files. It includes encrypting and decrypting PDF with AES 256, AES 128, RC4 (128 & 40) encryption algorithms.

Dependencies

• Node.js
• qpdf

Installation

• Install qpdf:
  • Download qpdf
  • Read qpdf manual for installation instructions.
• Install node-qpdf:

  npm install node-qpdf
  

Encryption

You can encrypt your PDF by following:

var qpdf = require('node-qpdf');

var options = {
    keyLength: 128,
    password: 'YOUR_PASSWORD_TO_ENCRYPT'
}

qpdf.encrypt(localFilePath, options);

Options for Encryption

The following are required options

• keyLength: - a number which defines the encryption algorithm to be used. Values can be 40, 128 and 256 only.
• password: - a string containing the secret password which will be further used to unlock the PDF.

You might want to set other options for each encryption algorithm inside restrictions: JSON according to the keyLength you choose :-

Key Length: 40

Option	Value	Description
print:	'y', 'n'	Determines whether or not to allow printing.
modify:	'y', 'n'	Determines whether or not to allow document modification.
extract:	'y', 'n'	Determines whether or not to allow text/image extraction.
annotate:	'y', 'n'	Determines whether or not to allow comments and form fill-in and signing.

Key Length: 128

Option	Value	Description
print:	'full', 'low', 'none'	full: allow full printing. low: allow low-resolution printing only. none: disallow printing.
modify:	'all', 'annotate', 'form', 'assembly', 'none'	all: allow full document modification. annotate: allow comment authoring and form operations. form: allow form field fill-in and signing. assembly: allow document assembly only. none: allow no modifications.
extract:	'y', 'n'	Determines whether or not to allow text/image extraction.
useAes:	'y', 'n'	AES encryption will be used instead of RC4 encryption.
accessibility:	'y', 'n'	Determines whether or not to allow accessibility to visually impaired.

Key Length: 256

Option	Value	Description
print:	'full', 'low', 'none'	full: allow full printing. low: allow low-resolution printing only. none: disallow printing.
modify:	'all', 'annotate', 'form', 'assembly', 'none'	all: allow full document modification. annotate: allow comment authoring and form operations. form: allow form field fill-in and signing. assembly: allow document assembly only. none: allow no modifications.
extract:	'y', 'n'	Determines whether or not to allow text/image extraction.
accessibility:	'y', 'n'	Determines whether or not to allow accessibility to visually impaired.

Examples

Render and Save:

var qpdf = require('node-qpdf');

var options = {
    keyLength: 128,
    password: 'YOUR_PASSWORD_TO_ENCRYPT',
    restrictions: {
        print: 'low',
        useAes: 'y'
    }
}

qpdf.encrypt(localFilePath, options, outputFilePath);

Render and Stream:

var qpdf = require('node-qpdf');

var options = {
    keyLength: 256,
    password: 'YOUR_PASSWORD_TO_ENCRYPT',
    restrictions: {
        modify: 'none',
        extract: 'n'
    }
}

var doc = qpdf.encrypt(localFilePath, options, outputFilePath);

doc.stdout.pipe(res);

res.writeHead(200, {
    'Content-Type': 'application/pdf',
    'Access-Control-Allow-Origin': '*',
    'Content-Disposition': 'inline; filename=order.pdf'
});

Decryption

You can decrypt your PDF by following:

var qpdf = require('node-qpdf');

qpdf.decrypt(localFilePath, 'YOUR_PASSWORD_TO_DECRYPT_PDF');

Examples

Render and Save:

var qpdf = require('node-qpdf');

qpdf.decrypt(localFilePath, 'YOUR_PASSWORD_TO_DECRYPT_PDF', outputFilePath);

Render and Stream:

var qpdf = require('node-qpdf');

var doc = qpdf.decrypt(localFilePath, 'YOUR_PASSWORD_TO_DECRYPT_PDF', outputFilePath);

doc.stdout.pipe(res);

res.writeHead(200, {
    'Content-Type': 'application/pdf',
    'Access-Control-Allow-Origin': '*',
    'Content-Disposition': 'inline; filename=order.pdf'
});

Meta

Maintained by Nishit Hirani

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/nrhirani/node-qpdf.

License

The npm package is available as open source under the terms of the MIT License.