Learn more at pdf-lib.js.org

Table of Contents

• Features
• Motivation
• Usage Examples
  • Create Document
  • Modify Document
  • Create Form
  • Fill Form
  • Flatten Form
  • Copy Pages
  • Embed PNG and JPEG Images
  • Embed PDF Pages
  • Embed Font and Measure Text
  • Add Attachments
  • Set Document Metadata
  • Read Document Metadata
  • Set Viewer Preferences
  • Read Viewer Preferences
  • Draw SVG Paths
• Deno Usage
• Complete Examples
• Installation
• Documentation
• Fonts and Unicode
• Creating and Filling Forms
• Limitations
• Help and Discussion
• Encryption Handling
• Migrating to v1.0.0
• Contributing
• Maintainership
• Tutorials and Cool Stuff
• Prior Art
• Git History Rewrite
• License

Features

• Create new PDFs
• Modify existing PDFs
• Create forms
• Fill forms
• Flatten forms
• Add Pages
• Insert Pages
• Remove Pages
• Copy pages between PDFs
• Draw Text
• Draw Images
• Draw PDF Pages
• Draw Vector Graphics
• Draw SVG Paths
• Measure width and height of text
• Embed Fonts (supports UTF-8 and UTF-16 character sets)
• Set document metadata
• Read document metadata
• Set viewer preferences
• Read viewer preferences
• Add attachments

Motivation

pdf-lib was created to address the JavaScript ecosystem's lack of robust support for PDF manipulation (especially for PDF modification).

Two of pdf-lib's distinguishing features are:

1. Supporting modification (editing) of existing documents.
2. Working in all JavaScript environments - not just in Node or the Browser.

There are other good open source JavaScript PDF libraries available. However, most of them can only create documents, they cannot modify existing ones. And many of them only work in particular environments.

Usage Examples

Create Document

This example produces this PDF.

Try the JSFiddle demo

1import { PDFDocument, StandardFonts, rgb } from 'pdf-lib'
2
3// Create a new PDFDocument
4const pdfDoc = await PDFDocument.create()
5
6// Embed the Times Roman font
7const timesRomanFont = await pdfDoc.embedFont(StandardFonts.TimesRoman)
8
9// Add a blank page to the document
10const page = pdfDoc.addPage()
11
12// Get the width and height of the page
13const { width, height } = page.getSize()
14
15// Draw a string of text toward the top of the page
16const fontSize = 30
17page.drawText('Creating PDFs in JavaScript is awesome!', {
18  x: 50,
19  y: height - 4 * fontSize,
20  size: fontSize,
21  font: timesRomanFont,
22  color: rgb(0, 0.53, 0.71),
23})
24
25// Serialize the PDFDocument to bytes (a Uint8Array)
26const pdfBytes = await pdfDoc.save()
27
28// For example, `pdfBytes` can be:
29//   • Written to a file in Node
30//   • Downloaded from the browser
31//   • Rendered in an <iframe>

Modify Document

This example produces this PDF (when this PDF is used for the existingPdfBytes variable).

Try the JSFiddle demo

1import { degrees, PDFDocument, rgb, StandardFonts } from 'pdf-lib';
2
3// This should be a Uint8Array or ArrayBuffer
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const existingPdfBytes = ...
8
9// Load a PDFDocument from the existing PDF bytes
10const pdfDoc = await PDFDocument.load(existingPdfBytes)
11
12// Embed the Helvetica font
13const helveticaFont = await pdfDoc.embedFont(StandardFonts.Helvetica)
14
15// Get the first page of the document
16const pages = pdfDoc.getPages()
17const firstPage = pages[0]
18
19// Get the width and height of the first page
20const { width, height } = firstPage.getSize()
21
22// Draw a string of text diagonally across the first page
23firstPage.drawText('This text was added with JavaScript!', {
24  x: 5,
25  y: height / 2 + 300,
26  size: 50,
27  font: helveticaFont,
28  color: rgb(0.95, 0.1, 0.1),
29  rotate: degrees(-45),
30})
31
32
33// Serialize the PDFDocument to bytes (a Uint8Array)
34const pdfBytes = await pdfDoc.save()
35
36// For example, `pdfBytes` can be:
37//   • Written to a file in Node
38//   • Downloaded from the browser
39//   • Rendered in an <iframe>

Create Form

This example produces this PDF.

Try the JSFiddle demo

See also Creating and Filling Forms

1import { PDFDocument } from 'pdf-lib'
2
3// Create a new PDFDocument
4const pdfDoc = await PDFDocument.create()
5
6// Add a blank page to the document
7const page = pdfDoc.addPage([550, 750])
8
9// Get the form so we can add fields to it
10const form = pdfDoc.getForm()
11
12// Add the superhero text field and description
13page.drawText('Enter your favorite superhero:', { x: 50, y: 700, size: 20 })
14
15const superheroField = form.createTextField('favorite.superhero')
16superheroField.setText('One Punch Man')
17superheroField.addToPage(page, { x: 55, y: 640 })
18
19// Add the rocket radio group, labels, and description
20page.drawText('Select your favorite rocket:', { x: 50, y: 600, size: 20 })
21
22page.drawText('Falcon Heavy', { x: 120, y: 560, size: 18 })
23page.drawText('Saturn IV', { x: 120, y: 500, size: 18 })
24page.drawText('Delta IV Heavy', { x: 340, y: 560, size: 18 })
25page.drawText('Space Launch System', { x: 340, y: 500, size: 18 })
26
27const rocketField = form.createRadioGroup('favorite.rocket')
28rocketField.addOptionToPage('Falcon Heavy', page, { x: 55, y: 540 })
29rocketField.addOptionToPage('Saturn IV', page, { x: 55, y: 480 })
30rocketField.addOptionToPage('Delta IV Heavy', page, { x: 275, y: 540 })
31rocketField.addOptionToPage('Space Launch System', page, { x: 275, y: 480 })
32rocketField.select('Saturn IV')
33
34// Add the gundam check boxes, labels, and description
35page.drawText('Select your favorite gundams:', { x: 50, y: 440, size: 20 })
36
37page.drawText('Exia', { x: 120, y: 400, size: 18 })
38page.drawText('Kyrios', { x: 120, y: 340, size: 18 })
39page.drawText('Virtue', { x: 340, y: 400, size: 18 })
40page.drawText('Dynames', { x: 340, y: 340, size: 18 })
41
42const exiaField = form.createCheckBox('gundam.exia')
43const kyriosField = form.createCheckBox('gundam.kyrios')
44const virtueField = form.createCheckBox('gundam.virtue')
45const dynamesField = form.createCheckBox('gundam.dynames')
46
47exiaField.addToPage(page, { x: 55, y: 380 })
48kyriosField.addToPage(page, { x: 55, y: 320 })
49virtueField.addToPage(page, { x: 275, y: 380 })
50dynamesField.addToPage(page, { x: 275, y: 320 })
51
52exiaField.check()
53dynamesField.check()
54
55// Add the planet dropdown and description
56page.drawText('Select your favorite planet*:', { x: 50, y: 280, size: 20 })
57
58const planetsField = form.createDropdown('favorite.planet')
59planetsField.addOptions(['Venus', 'Earth', 'Mars', 'Pluto'])
60planetsField.select('Pluto')
61planetsField.addToPage(page, { x: 55, y: 220 })
62
63// Add the person option list and description
64page.drawText('Select your favorite person:', { x: 50, y: 180, size: 18 })
65
66const personField = form.createOptionList('favorite.person')
67personField.addOptions([
68  'Julius Caesar',
69  'Ada Lovelace',
70  'Cleopatra',
71  'Aaron Burr',
72  'Mark Antony',
73])
74personField.select('Ada Lovelace')
75personField.addToPage(page, { x: 55, y: 70 })
76
77// Just saying...
78page.drawText(`* Pluto should be a planet too!`, { x: 15, y: 15, size: 15 })
79
80// Serialize the PDFDocument to bytes (a Uint8Array)
81const pdfBytes = await pdfDoc.save()
82
83// For example, `pdfBytes` can be:
84//   • Written to a file in Node
85//   • Downloaded from the browser
86//   • Rendered in an <iframe>

Fill Form

This example produces this PDF (when this PDF is used for the formPdfBytes variable, this image is used for the marioImageBytes variable, and this image is used for the emblemImageBytes variable).

Try the JSFiddle demo

See also Creating and Filling Forms

1import { PDFDocument } from 'pdf-lib'
2
3// These should be Uint8Arrays or ArrayBuffers
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const formPdfBytes = ...
8const marioImageBytes = ...
9const emblemImageBytes = ...
10
11// Load a PDF with form fields
12const pdfDoc = await PDFDocument.load(formPdfBytes)
13
14// Embed the Mario and emblem images
15const marioImage = await pdfDoc.embedPng(marioImageBytes)
16const emblemImage = await pdfDoc.embedPng(emblemImageBytes)
17
18// Get the form containing all the fields
19const form = pdfDoc.getForm()
20
21// Get all fields in the PDF by their names
22const nameField = form.getTextField('CharacterName 2')
23const ageField = form.getTextField('Age')
24const heightField = form.getTextField('Height')
25const weightField = form.getTextField('Weight')
26const eyesField = form.getTextField('Eyes')
27const skinField = form.getTextField('Skin')
28const hairField = form.getTextField('Hair')
29
30const alliesField = form.getTextField('Allies')
31const factionField = form.getTextField('FactionName')
32const backstoryField = form.getTextField('Backstory')
33const traitsField = form.getTextField('Feat+Traits')
34const treasureField = form.getTextField('Treasure')
35
36const characterImageField = form.getButton('CHARACTER IMAGE')
37const factionImageField = form.getTextField('Faction Symbol Image')
38
39// Fill in the basic info fields
40nameField.setText('Mario')
41ageField.setText('24 years')
42heightField.setText(`5' 1"`)
43weightField.setText('196 lbs')
44eyesField.setText('blue')
45skinField.setText('white')
46hairField.setText('brown')
47
48// Fill the character image field with our Mario image
49characterImageField.setImage(marioImage)
50
51// Fill in the allies field
52alliesField.setText(
53  [
54    `Allies:`,
55    `  • Princess Daisy`,
56    `  • Princess Peach`,
57    `  • Rosalina`,
58    `  • Geno`,
59    `  • Luigi`,
60    `  • Donkey Kong`,
61    `  • Yoshi`,
62    `  • Diddy Kong`,
63    ``,
64    `Organizations:`,
65    `  • Italian Plumbers Association`,
66  ].join('\n'),
67)
68
69// Fill in the faction name field
70factionField.setText(`Mario's Emblem`)
71
72// Fill the faction image field with our emblem image
73factionImageField.setImage(emblemImage)
74
75// Fill in the backstory field
76backstoryField.setText(
77  `Mario is a fictional character in the Mario video game franchise, owned by Nintendo and created by Japanese video game designer Shigeru Miyamoto. Serving as the company's mascot and the eponymous protagonist of the series, Mario has appeared in over 200 video games since his creation. Depicted as a short, pudgy, Italian plumber who resides in the Mushroom Kingdom, his adventures generally center upon rescuing Princess Peach from the Koopa villain Bowser. His younger brother and sidekick is Luigi.`,
78)
79
80// Fill in the traits field
81traitsField.setText(
82  [
83    `Mario can use three basic three power-ups:`,
84    `  • the Super Mushroom, which causes Mario to grow larger`,
85    `  • the Fire Flower, which allows Mario to throw fireballs`,
86    `  • the Starman, which gives Mario temporary invincibility`,
87  ].join('\n'),
88)
89
90// Fill in the treasure field
91treasureField.setText(['• Gold coins', '• Treasure chests'].join('\n'))
92
93// Serialize the PDFDocument to bytes (a Uint8Array)
94const pdfBytes = await pdfDoc.save()
95
96// For example, `pdfBytes` can be:
97//   • Written to a file in Node
98//   • Downloaded from the browser
99//   • Rendered in an <iframe>

Flatten Form

This example produces this PDF (when this PDF is used for the formPdfBytes variable).

Try the JSFiddle demo

1import { PDFDocument } from 'pdf-lib'
2
3// This should be a Uint8Array or ArrayBuffer
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const formPdfBytes = ...
8
9// Load a PDF with form fields
10const pdfDoc = await PDFDocument.load(formPdfBytes)
11
12// Get the form containing all the fields
13const form = pdfDoc.getForm()
14
15// Fill the form's fields
16form.getTextField('Text1').setText('Some Text');
17
18form.getRadioGroup('Group2').select('Choice1');
19form.getRadioGroup('Group3').select('Choice3');
20form.getRadioGroup('Group4').select('Choice1');
21
22form.getCheckBox('Check Box3').check();
23form.getCheckBox('Check Box4').uncheck();
24
25form.getDropdown('Dropdown7').select('Infinity');
26
27form.getOptionList('List Box6').select('Honda');
28
29// Flatten the form's fields
30form.flatten();
31
32// Serialize the PDFDocument to bytes (a Uint8Array)
33const pdfBytes = await pdfDoc.save()
34
35// For example, `pdfBytes` can be:
36//   • Written to a file in Node
37//   • Downloaded from the browser
38//   • Rendered in an <iframe>

Copy Pages

This example produces this PDF (when this PDF is used for the firstDonorPdfBytes variable and this PDF is used for the secondDonorPdfBytes variable).

Try the JSFiddle demo

1import { PDFDocument } from 'pdf-lib'
2
3// Create a new PDFDocument
4const pdfDoc = await PDFDocument.create()
5
6// These should be Uint8Arrays or ArrayBuffers
7// This data can be obtained in a number of different ways
8// If your running in a Node environment, you could use fs.readFile()
9// In the browser, you could make a fetch() call and use res.arrayBuffer()
10const firstDonorPdfBytes = ...
11const secondDonorPdfBytes = ...
12
13// Load a PDFDocument from each of the existing PDFs
14const firstDonorPdfDoc = await PDFDocument.load(firstDonorPdfBytes)
15const secondDonorPdfDoc = await PDFDocument.load(secondDonorPdfBytes)
16
17// Copy the 1st page from the first donor document, and
18// the 743rd page from the second donor document
19const [firstDonorPage] = await pdfDoc.copyPages(firstDonorPdfDoc, [0])
20const [secondDonorPage] = await pdfDoc.copyPages(secondDonorPdfDoc, [742])
21
22// Add the first copied page
23pdfDoc.addPage(firstDonorPage)
24
25// Insert the second copied page to index 0, so it will be the
26// first page in `pdfDoc`
27pdfDoc.insertPage(0, secondDonorPage)
28
29// Serialize the PDFDocument to bytes (a Uint8Array)
30const pdfBytes = await pdfDoc.save()
31
32// For example, `pdfBytes` can be:
33//   • Written to a file in Node
34//   • Downloaded from the browser
35//   • Rendered in an <iframe>

Embed PNG and JPEG Images

This example produces this PDF (when this image is used for the jpgImageBytes variable and this image is used for the pngImageBytes variable).

Try the JSFiddle demo

1import { PDFDocument } from 'pdf-lib'
2
3// These should be Uint8Arrays or ArrayBuffers
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const jpgImageBytes = ...
8const pngImageBytes = ...
9
10// Create a new PDFDocument
11const pdfDoc = await PDFDocument.create()
12
13// Embed the JPG image bytes and PNG image bytes
14const jpgImage = await pdfDoc.embedJpg(jpgImageBytes)
15const pngImage = await pdfDoc.embedPng(pngImageBytes)
16
17// Get the width/height of the JPG image scaled down to 25% of its original size
18const jpgDims = jpgImage.scale(0.25)
19
20// Get the width/height of the PNG image scaled down to 50% of its original size
21const pngDims = pngImage.scale(0.5)
22
23// Add a blank page to the document
24const page = pdfDoc.addPage()
25
26// Draw the JPG image in the center of the page
27page.drawImage(jpgImage, {
28  x: page.getWidth() / 2 - jpgDims.width / 2,
29  y: page.getHeight() / 2 - jpgDims.height / 2,
30  width: jpgDims.width,
31  height: jpgDims.height,
32})
33
34// Draw the PNG image near the lower right corner of the JPG image
35page.drawImage(pngImage, {
36  x: page.getWidth() / 2 - pngDims.width / 2 + 75,
37  y: page.getHeight() / 2 - pngDims.height,
38  width: pngDims.width,
39  height: pngDims.height,
40})
41
42// Serialize the PDFDocument to bytes (a Uint8Array)
43const pdfBytes = await pdfDoc.save()
44
45// For example, `pdfBytes` can be:
46//   • Written to a file in Node
47//   • Downloaded from the browser
48//   • Rendered in an <iframe>

Embed PDF Pages

This example produces this PDF (when this PDF is used for the americanFlagPdfBytes variable and this PDF is used for the usConstitutionPdfBytes variable).

Try the JSFiddle demo

1import { PDFDocument } from 'pdf-lib'
2
3// These should be Uint8Arrays or ArrayBuffers
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const americanFlagPdfBytes = ...
8const usConstitutionPdfBytes = ...
9
10// Create a new PDFDocument
11const pdfDoc = await PDFDocument.create()
12
13// Embed the American flag PDF bytes
14const [americanFlag] = await pdfDoc.embedPdf(americanFlagPdfBytes)
15
16// Load the U.S. constitution PDF bytes
17const usConstitutionPdf = await PDFDocument.load(usConstitutionPdfBytes)
18
19// Embed the second page of the constitution and clip the preamble
20const preamble = await pdfDoc.embedPage(usConstitutionPdf.getPages()[1], {
21  left: 55,
22  bottom: 485,
23  right: 300,
24  top: 575,
25})
26
27// Get the width/height of the American flag PDF scaled down to 30% of
28// its original size
29const americanFlagDims = americanFlag.scale(0.3)
30
31// Get the width/height of the preamble clipping scaled up to 225% of
32// its original size
33const preambleDims = preamble.scale(2.25)
34
35// Add a blank page to the document
36const page = pdfDoc.addPage()
37
38// Draw the American flag image in the center top of the page
39page.drawPage(americanFlag, {
40  ...americanFlagDims,
41  x: page.getWidth() / 2 - americanFlagDims.width / 2,
42  y: page.getHeight() - americanFlagDims.height - 150,
43})
44
45// Draw the preamble clipping in the center bottom of the page
46page.drawPage(preamble, {
47  ...preambleDims,
48  x: page.getWidth() / 2 - preambleDims.width / 2,
49  y: page.getHeight() / 2 - preambleDims.height / 2 - 50,
50})
51
52// Serialize the PDFDocument to bytes (a Uint8Array)
53const pdfBytes = await pdfDoc.save()
54
55// For example, `pdfBytes` can be:
56//   • Written to a file in Node
57//   • Downloaded from the browser
58//   • Rendered in an <iframe>

Embed Font and Measure Text

pdf-lib relies on a sister module to support embedding custom fonts: @pdf-lib/fontkit. You must add the @pdf-lib/fontkit module to your project and register it using pdfDoc.registerFontkit(...) before embedding custom fonts.

See below for detailed installation instructions on installing @pdf-lib/fontkit as a UMD or NPM module.

This example produces this PDF (when this font is used for the fontBytes variable).

Try the JSFiddle demo

1import { PDFDocument, rgb } from 'pdf-lib'
2import fontkit from '@pdf-lib/fontkit'
3
4// This should be a Uint8Array or ArrayBuffer
5// This data can be obtained in a number of different ways
6// If you're running in a Node environment, you could use fs.readFile()
7// In the browser, you could make a fetch() call and use res.arrayBuffer()
8const fontBytes = ...
9
10// Create a new PDFDocument
11const pdfDoc = await PDFDocument.create()
12
13// Register the `fontkit` instance
14pdfDoc.registerFontkit(fontkit)
15
16// Embed our custom font in the document
17const customFont = await pdfDoc.embedFont(fontBytes)
18
19// Add a blank page to the document
20const page = pdfDoc.addPage()
21
22// Create a string of text and measure its width and height in our custom font
23const text = 'This is text in an embedded font!'
24const textSize = 35
25const textWidth = customFont.widthOfTextAtSize(text, textSize)
26const textHeight = customFont.heightAtSize(textSize)
27
28// Draw the string of text on the page
29page.drawText(text, {
30  x: 40,
31  y: 450,
32  size: textSize,
33  font: customFont,
34  color: rgb(0, 0.53, 0.71),
35})
36
37// Draw a box around the string of text
38page.drawRectangle({
39  x: 40,
40  y: 450,
41  width: textWidth,
42  height: textHeight,
43  borderColor: rgb(1, 0, 0),
44  borderWidth: 1.5,
45})
46
47// Serialize the PDFDocument to bytes (a Uint8Array)
48const pdfBytes = await pdfDoc.save()
49
50// For example, `pdfBytes` can be:
51//   • Written to a file in Node
52//   • Downloaded from the browser
53//   • Rendered in an <iframe>

Add Attachments

This example produces this PDF (when this image is used for the jpgAttachmentBytes variable and this PDF is used for the pdfAttachmentBytes variable).

Try the JSFiddle demo

1import { PDFDocument } from 'pdf-lib'
2
3// These should be Uint8Arrays or ArrayBuffers
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const jpgAttachmentBytes = ...
8const pdfAttachmentBytes = ...
9
10// Create a new PDFDocument
11const pdfDoc = await PDFDocument.create()
12
13// Add the JPG attachment
14await pdfDoc.attach(jpgAttachmentBytes, 'cat_riding_unicorn.jpg', {
15  mimeType: 'image/jpeg',
16  description: 'Cool cat riding a unicorn! ????????????️',
17  creationDate: new Date('2019/12/01'),
18  modificationDate: new Date('2020/04/19'),
19})
20
21// Add the PDF attachment
22await pdfDoc.attach(pdfAttachmentBytes, 'us_constitution.pdf', {
23  mimeType: 'application/pdf',
24  description: 'Constitution of the United States ????????????',
25  creationDate: new Date('1787/09/17'),
26  modificationDate: new Date('1992/05/07'),
27})
28
29// Add a page with some text
30const page = pdfDoc.addPage();
31page.drawText('This PDF has two attachments', { x: 135, y: 415 })
32
33// Serialize the PDFDocument to bytes (a Uint8Array)
34const pdfBytes = await pdfDoc.save()
35
36// For example, `pdfBytes` can be:
37//   • Written to a file in Node
38//   • Downloaded from the browser
39//   • Rendered in an <iframe>

Set Document Metadata

This example produces this PDF.

Try the JSFiddle demo

1import { PDFDocument, StandardFonts } from 'pdf-lib'
2
3// Create a new PDFDocument
4const pdfDoc = await PDFDocument.create()
5
6// Embed the Times Roman font
7const timesRomanFont = await pdfDoc.embedFont(StandardFonts.TimesRoman)
8
9// Add a page and draw some text on it
10const page = pdfDoc.addPage([500, 600])
11page.setFont(timesRomanFont)
12page.drawText('The Life of an Egg', { x: 60, y: 500, size: 50 })
13page.drawText('An Epic Tale of Woe', { x: 125, y: 460, size: 25 })
14
15// Set all available metadata fields on the PDFDocument. Note that these fields
16// are visible in the "Document Properties" section of most PDF readers.
17pdfDoc.setTitle('???? The Life of an Egg ????')
18pdfDoc.setAuthor('Humpty Dumpty')
19pdfDoc.setSubject('???? An Epic Tale of Woe ????')
20pdfDoc.setKeywords(['eggs', 'wall', 'fall', 'king', 'horses', 'men'])
21pdfDoc.setProducer('PDF App 9000 ????')
22pdfDoc.setCreator('pdf-lib (https://github.com/Hopding/pdf-lib)')
23pdfDoc.setCreationDate(new Date('2018-06-24T01:58:37.228Z'))
24pdfDoc.setModificationDate(new Date('2019-12-21T07:00:11.000Z'))
25
26// Serialize the PDFDocument to bytes (a Uint8Array)
27const pdfBytes = await pdfDoc.save()
28
29// For example, `pdfBytes` can be:
30//   • Written to a file in Node
31//   • Downloaded from the browser
32//   • Rendered in an <iframe>

Read Document Metadata

Try the JSFiddle demo

1import { PDFDocument } from 'pdf-lib'
2
3// This should be a Uint8Array or ArrayBuffer
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const existingPdfBytes = ...
8
9// Load a PDFDocument without updating its existing metadata
10const pdfDoc = await PDFDocument.load(existingPdfBytes, {
11  updateMetadata: false
12})
13
14// Print all available metadata fields
15console.log('Title:', pdfDoc.getTitle())
16console.log('Author:', pdfDoc.getAuthor())
17console.log('Subject:', pdfDoc.getSubject())
18console.log('Creator:', pdfDoc.getCreator())
19console.log('Keywords:', pdfDoc.getKeywords())
20console.log('Producer:', pdfDoc.getProducer())
21console.log('Creation Date:', pdfDoc.getCreationDate())
22console.log('Modification Date:', pdfDoc.getModificationDate())

This script outputs the following (when this PDF is used for the existingPdfBytes variable):

Title: Microsoft Word - Basic Curriculum Vitae example.doc
Author: Administrator
Subject: undefined
Creator: PScript5.dll Version 5.2
Keywords: undefined
Producer: Acrobat Distiller 8.1.0 (Windows)
Creation Date: 2010-07-29T14:26:00.000Z
Modification Date: 2010-07-29T14:26:00.000Z

Set Viewer Preferences

1import {
2  PDFDocument,
3  StandardFonts,
4  NonFullScreenPageMode,
5  ReadingDirection,
6  PrintScaling,
7  Duplex,
8  PDFName,
9} from 'pdf-lib'
10
11// Create a new PDFDocument
12const pdfDoc = await PDFDocument.create()
13
14// Embed the Times Roman font
15const timesRomanFont = await pdfDoc.embedFont(StandardFonts.TimesRoman)
16
17// Add a page and draw some text on it
18const page = pdfDoc.addPage([500, 600])
19page.setFont(timesRomanFont)
20page.drawText('The Life of an Egg', { x: 60, y: 500, size: 50 })
21page.drawText('An Epic Tale of Woe', { x: 125, y: 460, size: 25 })
22
23// Set all available viewer preferences on the PDFDocument:
24const viewerPrefs = pdfDoc.catalog.getOrCreateViewerPreferences()
25viewerPrefs.setHideToolbar(true)
26viewerPrefs.setHideMenubar(true)
27viewerPrefs.setHideWindowUI(true)
28viewerPrefs.setFitWindow(true)
29viewerPrefs.setCenterWindow(true)
30viewerPrefs.setDisplayDocTitle(true)
31
32// Set the PageMode (otherwise setting NonFullScreenPageMode has no meaning)
33pdfDoc.catalog.set(PDFName.of('PageMode'), PDFName.of('FullScreen'))
34
35// Set what happens when fullScreen is closed
36viewerPrefs.setNonFullScreenPageMode(NonFullScreenPageMode.UseOutlines)
37
38viewerPrefs.setReadingDirection(ReadingDirection.L2R)
39viewerPrefs.setPrintScaling(PrintScaling.None)
40viewerPrefs.setDuplex(Duplex.DuplexFlipLongEdge)
41viewerPrefs.setPickTrayByPDFSize(true)
42
43// We can set the default print range to only the first page
44viewerPrefs.setPrintPageRange({ start: 0, end: 0 })
45
46// Or we can supply noncontiguous ranges (e.g. pages 1, 3, and 5-7)
47viewerPrefs.setPrintPageRange([
48  { start: 0, end: 0 },
49  { start: 2, end: 2 },
50  { start: 4, end: 6 },
51])
52
53viewerPrefs.setNumCopies(2)
54
55// Serialize the PDFDocument to bytes (a Uint8Array)
56const pdfBytes = await pdfDoc.save()
57
58// For example, `pdfBytes` can be:
59//   • Written to a file in Node
60//   • Downloaded from the browser
61//   • Rendered in an <iframe>

Read Viewer Preferences

1import { PDFDocument } from 'pdf-lib'
2
3// This should be a Uint8Array or ArrayBuffer
4// This data can be obtained in a number of different ways
5// If your running in a Node environment, you could use fs.readFile()
6// In the browser, you could make a fetch() call and use res.arrayBuffer()
7const existingPdfBytes = ...
8
9// Load a PDFDocument without updating its existing metadata
10const pdfDoc = await PDFDocument.load(existingPdfBytes)
11const viewerPrefs = pdfDoc.catalog.getOrCreateViewerPreferences()
12
13// Print all available viewer preference fields
14console.log('HideToolbar:', viewerPrefs.getHideToolbar())
15console.log('HideMenubar:', viewerPrefs.getHideMenubar())
16console.log('HideWindowUI:', viewerPrefs.getHideWindowUI())
17console.log('FitWindow:', viewerPrefs.getFitWindow())
18console.log('CenterWindow:', viewerPrefs.getCenterWindow())
19console.log('DisplayDocTitle:', viewerPrefs.getDisplayDocTitle())
20console.log('NonFullScreenPageMode:', viewerPrefs.getNonFullScreenPageMode())
21console.log('ReadingDirection:', viewerPrefs.getReadingDirection())
22console.log('PrintScaling:', viewerPrefs.getPrintScaling())
23console.log('Duplex:', viewerPrefs.getDuplex())
24console.log('PickTrayByPDFSize:', viewerPrefs.getPickTrayByPDFSize())
25console.log('PrintPageRange:', viewerPrefs.getPrintPageRange())
26console.log('NumCopies:', viewerPrefs.getNumCopies())

This script outputs the following (when this PDF is used for the existingPdfBytes variable):

HideToolbar: true
HideMenubar: true
HideWindowUI: false
FitWindow: true
CenterWindow: true
DisplayDocTitle: true
NonFullScreenPageMode: UseNone
ReadingDirection: R2L
PrintScaling: None
Duplex: DuplexFlipLongEdge
PickTrayByPDFSize: true
PrintPageRange: [ { start: 1, end: 1 }, { start: 3, end: 4 } ]
NumCopies: 2

Draw SVG Paths

This example produces this PDF.

Try the JSFiddle demo

1import { PDFDocument, rgb } from 'pdf-lib'
2
3// SVG path for a wavy line
4const svgPath =
5  'M 0,20 L 100,160 Q 130,200 150,120 C 190,-40 200,200 300,150 L 400,90'
6
7// Create a new PDFDocument
8const pdfDoc = await PDFDocument.create()
9
10// Add a blank page to the document
11const page = pdfDoc.addPage()
12page.moveTo(100, page.getHeight() - 5)
13
14// Draw the SVG path as a black line
15page.moveDown(25)
16page.drawSvgPath(svgPath)
17
18// Draw the SVG path as a thick green line
19page.moveDown(200)
20page.drawSvgPath(svgPath, { borderColor: rgb(0, 1, 0), borderWidth: 5 })
21
22// Draw the SVG path and fill it with red
23page.moveDown(200)
24page.drawSvgPath(svgPath, { color: rgb(1, 0, 0) })
25
26// Draw the SVG path at 50% of its original size
27page.moveDown(200)
28page.drawSvgPath(svgPath, { scale: 0.5 })
29
30// Serialize the PDFDocument to bytes (a Uint8Array)
31const pdfBytes = await pdfDoc.save()
32
33// For example, `pdfBytes` can be:
34//   • Written to a file in Node
35//   • Downloaded from the browser
36//   • Rendered in an <iframe>

Deno Usage

pdf-lib fully supports the exciting new Deno runtime! All of the usage examples work in Deno. The only thing you need to do is change the imports for pdf-lib and @pdf-lib/fontkit to use the Skypack CDN, because Deno requires all modules to be referenced via URLs.

See also How to Create and Modify PDF Files in Deno With pdf-lib

Creating a Document with Deno

Below is the create document example modified for Deno:

1import {
2  PDFDocument,
3  StandardFonts,
4  rgb,
5} from 'https://cdn.skypack.dev/pdf-lib@^1.11.1?dts';
6
7const pdfDoc = await PDFDocument.create();
8const timesRomanFont = await pdfDoc.embedFont(StandardFonts.TimesRoman);
9
10const page = pdfDoc.addPage();
11const { width, height } = page.getSize();
12const fontSize = 30;
13page.drawText('Creating PDFs in JavaScript is awesome!', {
14  x: 50,
15  y: height - 4 * fontSize,
16  size: fontSize,
17  font: timesRomanFont,
18  color: rgb(0, 0.53, 0.71),
19});
20
21const pdfBytes = await pdfDoc.save();
22
23await Deno.writeFile('out.pdf', pdfBytes);

If you save this script as create-document.ts, you can execute it using Deno with the following command:

deno run --allow-write create-document.ts

The resulting out.pdf file will look like this PDF.

Embedding a Font with Deno

Here's a slightly more complicated example demonstrating how to embed a font and measure text in Deno:

1import {
2  degrees,
3  PDFDocument,
4  rgb,
5  StandardFonts,
6} from 'https://cdn.skypack.dev/pdf-lib@^1.11.1?dts';
7import fontkit from 'https://cdn.skypack.dev/@pdf-lib/fontkit@^1.0.0?dts';
8
9const url = 'https://pdf-lib.js.org/assets/ubuntu/Ubuntu-R.ttf';
10const fontBytes = await fetch(url).then((res) => res.arrayBuffer());
11
12const pdfDoc = await PDFDocument.create();
13
14pdfDoc.registerFontkit(fontkit);
15const customFont = await pdfDoc.embedFont(fontBytes);
16
17const page = pdfDoc.addPage();
18
19const text = 'This is text in an embedded font!';
20const textSize = 35;
21const textWidth = customFont.widthOfTextAtSize(text, textSize);
22const textHeight = customFont.heightAtSize(textSize);
23
24page.drawText(text, {
25  x: 40,
26  y: 450,
27  size: textSize,
28  font: customFont,
29  color: rgb(0, 0.53, 0.71),
30});
31page.drawRectangle({
32  x: 40,
33  y: 450,
34  width: textWidth,
35  height: textHeight,
36  borderColor: rgb(1, 0, 0),
37  borderWidth: 1.5,
38});
39
40const pdfBytes = await pdfDoc.save();
41
42await Deno.writeFile('out.pdf', pdfBytes);

If you save this script as custom-font.ts, you can execute it with the following command:

deno run --allow-write --allow-net custom-font.ts

The resulting out.pdf file will look like this PDF.

Complete Examples

The usage examples provide code that is brief and to the point, demonstrating the different features of pdf-lib. You can find complete working examples in the apps/ directory. These apps are used to do manual testing of pdf-lib before every release (in addition to the automated tests).

There are currently four apps:

• node - contains tests for pdf-lib in Node environments. These tests are a handy reference when trying to save/load PDFs, fonts, or images with pdf-lib from the filesystem. They also allow you to quickly open your PDFs in different viewers (Acrobat, Preview, Foxit, Chrome, Firefox, etc...) to ensure compatibility.
• web - contains tests for pdf-lib in browser environments. These tests are a handy reference when trying to save/load PDFs, fonts, or images with pdf-lib in a browser environment.
• rn - contains tests for pdf-lib in React Native environments. These tests are a handy reference when trying to save/load PDFs, fonts, or images with pdf-lib in a React Native environment.
• deno - contains tests for pdf-lib in Deno environments. These tests are a handy reference when trying to save/load PDFs, fonts, or images with pdf-lib from the filesystem.

Installation

NPM Module

To install the latest stable version:

1# With npm
2npm install --save pdf-lib
3
4# With yarn
5yarn add pdf-lib

This assumes you're using npm or yarn as your package manager.

UMD Module

You can also download pdf-lib as a UMD module from unpkg or jsDelivr. The UMD builds have been compiled to ES5, so they should work in any modern browser. UMD builds are useful if you aren't using a package manager or module bundler. For example, you can use them directly in the <script> tag of an HTML page.

The following builds are available:

• https://unpkg.com/pdf-lib/dist/pdf-lib.js
• https://unpkg.com/pdf-lib/dist/pdf-lib.min.js
• https://cdn.jsdelivr.net/npm/pdf-lib/dist/pdf-lib.js
• https://cdn.jsdelivr.net/npm/pdf-lib/dist/pdf-lib.min.js

NOTE: if you are using the CDN scripts in production, you should include a specific version number in the URL, for example:

• https://unpkg.com/pdf-lib@1.4.0/dist/pdf-lib.min.js
• https://cdn.jsdelivr.net/npm/pdf-lib@1.4.0/dist/pdf-lib.min.js

When using a UMD build, you will have access to a global window.PDFLib variable. This variable contains all of the classes and functions exported by pdf-lib. For example:

1// NPM module
2import { PDFDocument, rgb } from 'pdf-lib';
3
4// UMD module
5var PDFDocument = PDFLib.PDFDocument;
6var rgb = PDFLib.rgb;

Fontkit Installation

pdf-lib relies upon a sister module to support embedding custom fonts: @pdf-lib/fontkit. You must add the @pdf-lib/fontkit module to your project and register it using pdfDoc.registerFontkit(...) before embedding custom fonts (see the font embedding example). This module is not included by default because not all users need it, and it increases bundle size.

Installing this module is easy. Just like pdf-lib itself, @pdf-lib/fontkit can be installed with npm/yarn or as a UMD module.

Fontkit NPM Module

1# With npm
2npm install --save @pdf-lib/fontkit
3
4# With yarn
5yarn add @pdf-lib/fontkit

To register the fontkit instance:

1import { PDFDocument } from 'pdf-lib'
2import fontkit from '@pdf-lib/fontkit'
3
4const pdfDoc = await PDFDocument.create()
5pdfDoc.registerFontkit(fontkit)

Fontkit UMD Module

The following builds are available:

• https://unpkg.com/@pdf-lib/fontkit/dist/fontkit.umd.js
• https://unpkg.com/@pdf-lib/fontkit/dist/fontkit.umd.min.js
• https://cdn.jsdelivr.net/npm/@pdf-lib/fontkit/dist/fontkit.umd.js
• https://cdn.jsdelivr.net/npm/@pdf-lib/fontkit/dist/fontkit.umd.min.js

NOTE: if you are using the CDN scripts in production, you should include a specific version number in the URL, for example:

• https://unpkg.com/@pdf-lib/fontkit@0.0.4/dist/fontkit.umd.min.js
• https://cdn.jsdelivr.net/npm/@pdf-lib/fontkit@0.0.4/dist/fontkit.umd.min.js

When using a UMD build, you will have access to a global window.fontkit variable. To register the fontkit instance:

1var pdfDoc = await PDFLib.PDFDocument.create()
2pdfDoc.registerFontkit(fontkit)

Documentation

API documentation is available on the project site at https://pdf-lib.js.org/docs/api/.

The repo for the project site (and generated documentation files) is located here: https://github.com/Hopding/pdf-lib-docs.

Fonts and Unicode

When working with PDFs, you will frequently come across the terms "character encoding" and "font". If you have experience in web development, you may wonder why these are so prevalent. Aren't they just annoying details that you shouldn't need to worry about? Shouldn't PDF libraries and readers be able to handle all of this for you like web browsers can? Unfortunately, this is not the case. The nature of the PDF file format makes it very difficult to avoid thinking about character encodings and fonts when working with PDFs.

pdf-lib does its best to simplify things for you. But it can't perform magic. This means you should be aware of the following:

• There are 14 standard fonts defined in the PDF specification. They are as follows: Times Roman (normal, bold, and italic), Helvetica (normal, bold, and italic), Courier (normal, bold, and italic), ZapfDingbats (normal), and Symbol (normal). These 14 fonts are guaranteed to be available in PDF readers. As such, you do not need to embed any font data if you wish to use one of these fonts. You can use a standard font like so:

  1import { PDFDocument, StandardFonts } from 'pdf-lib'
  2const pdfDoc = await PDFDocument.create()
  3const courierFont = await pdfDoc.embedFont(StandardFonts.Courier)
  4const page = pdfDoc.addPage()
  5page.drawText('Some boring latin text in the Courier font', {
  6  font: courierFont,
  7})

• The standard fonts do not support all characters available in Unicode. The Times Roman, Helvetica, and Courier fonts use WinAnsi encoding (aka Windows-1252). The WinAnsi character set only supports 218 characters in the Latin alphabet. For this reason, many users will find the standard fonts insufficient for their use case. This is unfortunate, but there's nothing that PDF libraries can do to change this. This is a result of the PDF specification and its age. Note that the ZapfDingbats and Symbol fonts use their own specialized encodings that support 203 and 194 characters, respectively. However, the characters they support are not useful for most use cases. See here for an example of all 14 standard fonts.
• You can use characters outside the Latin alphabet by embedding your own fonts. Embedding your own font requires to you load the font data (from a file or via a network request, for example) and pass it to the embedFont method. When you embed your own font, you can use any Unicode characters that it supports. This capability frees you from the limitations imposed by the standard fonts. Most PDF files use embedded fonts. You can embed and use a custom font like so (see also):

  1import { PDFDocument } from 'pdf-lib'
  2import fontkit from '@pdf-lib/fontkit'
  3
  4const url = 'https://pdf-lib.js.org/assets/ubuntu/Ubuntu-R.ttf'
  5const fontBytes = await fetch(url).then((res) => res.arrayBuffer())
  6
  7const pdfDoc = await PDFDocument.create()
  8
  9pdfDoc.registerFontkit(fontkit)
  10const ubuntuFont = await pdfDoc.embedFont(fontBytes)
  11
  12const page = pdfDoc.addPage()
  13page.drawText('Some fancy Unicode text in the ŪЬȕǹƚü font', {
  14  font: ubuntuFont,
  15})

Note that encoding errors will be thrown if you try to use a character with a font that does not support it. For example, Ω is not in the WinAnsi character set. So trying to draw it on a page with the standard Helvetica font will throw the following error:

Error: WinAnsi cannot encode "Ω" (0x03a9)
    at Encoding.encodeUnicodeCodePoint

Font Subsetting

Embedding a font in a PDF document will typically increase the file's size. You can reduce the amount a file's size is increased by subsetting the font so that only the necessary characters are embedded. You can subset a font by setting the subset option to true. For example:

1const font = await pdfDoc.embedFont(fontBytes, { subset: true });

Note that subsetting does not work for all fonts. See https://github.com/Hopding/pdf-lib/issues/207#issuecomment-537210471 for additional details.

Creating and Filling Forms

pdf-lib can create, fill, and read PDF form fields. The following field types are supported:

• Buttons
• Check Boxes
• Dropdowns
• Option Lists
• Radio Groups
• Text Fields

See the form creation and form filling usage examples for code samples. Tests 1, 14, 15, 16, and 17 in the complete examples contain working example code for form creation and filling in a variety of different JS environments.

IMPORTANT: The default font used to display text in buttons, dropdowns, option lists, and text fields is the standard Helvetica font. This font only supports characters in the latin alphabet (see Fonts and Unicode for details). This means that if any of these field types are created or modified to contain text outside the latin alphabet (as is often the case), you will need to embed and use a custom font to update the field appearances. Otherwise an error will be thrown (likely when you save the PDFDocument).

You can use an embedded font when filling form fields as follows:

1import { PDFDocument } from 'pdf-lib';
2import fontkit from '@pdf-lib/fontkit';
3
4// Fetch the PDF with form fields
5const formUrl = 'https://pdf-lib.js.org/assets/dod_character.pdf';
6const formBytes = await fetch(formUrl).then((res) => res.arrayBuffer());
7
8// Fetch the Ubuntu font
9const fontUrl = 'https://pdf-lib.js.org/assets/ubuntu/Ubuntu-R.ttf';
10const fontBytes = await fetch(fontUrl).then((res) => res.arrayBuffer());
11
12// Load the PDF with form fields
13const pdfDoc = await PDFDocument.load(formBytes);
14
15// Embed the Ubuntu font
16pdfDoc.registerFontkit(fontkit);
17const ubuntuFont = await pdfDoc.embedFont(fontBytes);
18
19// Get two text fields from the form
20const form = pdfDoc.getForm();
21const nameField = form.getTextField('CharacterName 2');
22const ageField = form.getTextField('Age');
23
24// Fill the text fields with some fancy Unicode characters (outside
25// the WinAnsi latin character set)
26nameField.setText('Ӎӑȑїõ');
27ageField.setText('24 ŷȇȁŗš');
28
29// **Key Step:** Update the field appearances with the Ubuntu font
30form.updateFieldAppearances(ubuntuFont);
31
32// Save the PDF with filled form fields
33const pdfBytes = await pdfDoc.save();

Handy Methods for Filling, Creating, and Reading Form Fields

Existing form fields can be accessed with the following methods of PDFForm:

• PDFForm.getButton
• PDFForm.getCheckBox
• PDFForm.getDropdown
• PDFForm.getOptionList
• PDFForm.getRadioGroup
• PDFForm.getTextField

New form fields can be created with the following methods of PDFForm:

• PDFForm.createButton
• PDFForm.createCheckBox
• PDFForm.createDropdown
• PDFForm.createOptionList
• PDFForm.createRadioGroup
• PDFForm.createTextField

Below are some of the most commonly used methods for reading and filling the aforementioned subclasses of PDFField:

• PDFCheckBox.check
• PDFCheckBox.uncheck
• PDFCheckBox.isChecked

---

• PDFDropdown.select
• PDFDropdown.clear
• PDFDropdown.getSelected
• PDFDropdown.getOptions
• PDFDropdown.addOptions

---

• PDFOptionList.select
• PDFOptionList.clear
• PDFOptionList.getSelected
• PDFOptionList.getOptions
• PDFOptionList.addOptions

---

• PDFRadioGroup.select
• PDFRadioGroup.clear
• PDFRadioGroup.getSelected
• PDFRadioGroup.getOptions
• PDFRadioGroup.addOptionToPage

---

• PDFTextField.setText
• PDFTextField.getText
• PDFTextField.setMaxLength
• PDFTextField.getMaxLength
• PDFTextField.removeMaxLength

Limitations

• pdf-lib can extract the content of text fields (see PDFTextField.getText), but it cannot extract plain text on a page outside of a form field. This is a difficult feature to implement, but it is within the scope of this library and may be added to pdf-lib in the future. See #93, #137, #177, #329, and #380.
• pdf-lib can remove and edit the content of text fields (see PDFTextField.setText), but it does not provide APIs for removing or editing text on a page outside of a form field. This is also a difficult feature to implement, but is within the scope of pdf-lib and may be added in the future. See #93, #137, #177, #329, and #380.
• pdf-lib does not support the use of HTML or CSS when adding content to a PDF. Similarly, pdf-lib cannot embed HTML/CSS content into PDFs. As convenient as such a feature might be, it would be extremely difficult to implement and is far beyond the scope of this library. If this capability is something you need, consider using Puppeteer.

Help and Discussion

Discussions is the best place to chat with us, ask questions, and learn more about pdf-lib!

See also MAINTAINERSHIP.md#communication and MAINTAINERSHIP.md#discord.

Encryption Handling

pdf-lib does not currently support encrypted documents. You should not use pdf-lib with encrypted documents. However, this is a feature that could be added to pdf-lib. Please create an issue if you would find this feature helpful!

When an encrypted document is passed to PDFDocument.load(...), an error will be thrown:

1import { PDFDocument, EncryptedPDFError } from 'pdf-lib'
2
3const encryptedPdfBytes = ...
4
5// Assignment fails. Throws an `EncryptedPDFError`.
6const pdfDoc = PDFDocument.load(encryptedPdfBytes)

This default behavior is usually what you want. It allows you to easily detect if a given document is encrypted, and it prevents you from trying to modify it. However, if you really want to load the document, you can use the { ignoreEncryption: true } option:

1import { PDFDocument } from 'pdf-lib'
2
3const encryptedPdfBytes = ...
4
5// Assignment succeeds. Does not throw an error.
6const pdfDoc = PDFDocument.load(encryptedPdfBytes, { ignoreEncryption: true })

Note that using this option does not decrypt the document. This means that any modifications you attempt to make on the returned PDFDocument may fail, or have unexpected results.

You should not use this option. It only exists for backwards compatibility reasons.

Contributing

We welcome contributions from the open source community! If you are interested in contributing to pdf-lib, please take a look at the CONTRIBUTING.md file. It contains information to help you get pdf-lib setup and running on your machine. (We try to make this as simple and fast as possible! :rocket:)

Maintainership

Check out MAINTAINERSHIP.md for details on how this repo is maintained and how we use issues, PRs, and discussions.

Tutorials and Cool Stuff

• labelmake - a library for declarative PDF generation created by @hand-dot
• Möbius Printing helper - a tool created by @shreevatsa
• Extract PDF pages - a tool created by @shreevatsa
• Travel certificate generator - a tool that creates travel certificates for French citizens under quarantine due to COVID-19
• How to use pdf-lib in AWS Lambdas - a tutorial written by Crespo Wang
• Working With PDFs in Node.js Using pdf-lib - a tutorial by Valeri Karpov
• Electron app for resizing PDFs - a tool created by @vegarringdal
• PDF Shelter - online PDF manipulation tools by Lucas Morais

Prior Art

• pdfkit is a PDF generation library for Node and the Browser. This library was immensely helpful as a reference and existence proof when creating pdf-lib. pdfkit's code for font embedding, PNG embedding, and JPG embedding was especially useful.
• pdf.js is a PDF rendering library for the Browser. This library was helpful as a reference when writing pdf-lib's parser. Some of the code for stream decoding was ported directly to TypeScript for use in pdf-lib.
• pdfbox is a PDF generation and modification library written in Java. This library was an invaluable reference when implementing form creation and filling APIs for pdf-lib.
• jspdf is a PDF generation library for the browser.
• pdfmake is a PDF generation library for the browser.
• hummus is a PDF generation and modification library for Node environments. hummus is a Node wrapper around a C++ library, so it doesn't work in many JavaScript environments - like the Browser or React Native.
• react-native-pdf-lib is a PDF generation and modification library for React Native environments. react-native-pdf-lib is a wrapper around C++ and Java libraries.
• pdfassembler is a PDF generation and modification library for Node and the browser. It requires some knowledge about the logical structure of PDF documents to use.

Git History Rewrite

This repo used to contain a file called pdf_specification.pdf in the root directory. This was a copy of the PDF 1.7 specification, which is made freely available by Adobe. On 8/30/2021, we received a DMCA complaint requiring us to remove the file from this repo. Simply removing the file via a new commit to master was insufficient to satisfy the complaint. The file needed to be completely removed from the repo's git history. Unfortunately, the file was added over two years ago, this meant we had to rewrite the repo's git history and force push to master ????.

Steps We Took

We removed the file and rewrote the repo's history using BFG Repo-Cleaner as outlined here. For full transparency, here are the exact commands we ran:

$ git clone git@github.com:Hopding/pdf-lib.git
$ cd pdf-lib
$ rm pdf_specification.pdf
$ git commit -am 'Remove pdf_specification.pdf'
$ bfg --delete-files pdf_specification.pdf
$ git reflog expire --expire=now --all && git gc --prune=now --aggressive
$ git push --force

Why Should I Care?

If you're a user of pdf-lib, you shouldn't care! Just keep on using pdf-lib like normal ???? ✨!

If you are a pdf-lib developer (meaning you've forked pdf-lib and/or have an open PR) then this does impact you. If you forked or cloned the repo prior to 8/30/2021 then your fork's git history is out of sync with this repo's master branch. Unfortunately, this will likely be a headache for you to deal with. Sorry! We didn't want to rewrite the history, but there really was no alternative.

It's important to note that pdf-lib's source code has not changed at all. It's exactly the same as it was before the git history rewrite. The repo still has the exact same number of commits (and even the same commit contents, except for the commit that added pdf_specification.pdf). What has changed are the SHAs of those commits.

The simplest way to deal with this fact is to:

1. Reclone pdf-lib
2. Manually copy any changes you've made from your old clone to the new one
3. Use your new clone going forward
4. Reopen your unmerged PRs using your new clone

See this StackOverflow answer for a great, in depth explanation of what a git history rewrite entails.

License

MIT