switch from CommonJS to ESM

.github/workflows/test.yml

@@ -16,7 +16,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [14.x, 16.x, 18.x]
+        node-version: [14.x, 16.x, 18.x, 20.x]
 
     steps:
     - uses: actions/checkout@v2

README.md

@@ -1,9 +1,12 @@
 # Description
 
-This node.js library can **merge multiple PDF documents**, or parts of them, to one new PDF document. It's only dependency is [pdf-lib](https://pdf-lib.js.org/) so it can run in any javascript-only environment **without any external dependencies**.
+This node.js library can **merge multiple PDF documents**, or parts of them, to one new PDF document. It's only dependency is [pdf-lib](https://pdf-lib.js.org/) so it can run in any javascript-only environment **without any non-javascript dependencies**.
 
-> If you are searching for the legacy version based on 
+## Legacy notes
+
+* If you are searching for the legacy version based on 
 [pdfjs](https://www.npmjs.com/package/pdfjs) please install a [v3 release](https://github.com/nbesli/pdf-merger-js/releases?q=v3&expanded=true). Since [v4](https://github.com/nbesli/pdf-merger-js/releases?q=v4&expanded=true) we use [pdf-lib](https://pdf-lib.js.org/) instead.
+* If you are searching for a legacy version using CommonJS modules please install a [v4 release](https://github.com/nbesli/pdf-merger-js/releases?q=v4&expanded=true). Since [v5](https://github.com/nbesli/pdf-merger-js/releases?q=v5&expanded=true) we use the modern ESM ("import") instead of the CommonJS ("require) module standard.
 
 This library is inspired by the [PHP library PDFMerger](https://github.com/myokyawhtun/PDFMerger) and has a very similar API.
 
@@ -22,10 +25,10 @@ The node.js version has the following export functions:
 * `setMetadata` set Metadata for producer, author, title or creator.
 * `reset` resets the internal state of the document, to start again.
 
-### async node.js example
+#### async node.js example
 
 ```js
-const PDFMerger = require('pdf-merger-js');
+import PDFMerger from 'pdf-merger-js';
 
 var merger = new PDFMerger();
 
@@ -37,6 +40,14 @@ var merger = new PDFMerger();
   await merger.add('pdf3.pdf', '3 to 5'); //merge pages 3 to 5 (3,4,5)
   await merger.add('pdf3.pdf', '3-5'); //merge pages 3 to 5 (3,4,5)
 
+  // Set metadata
+  await merger.setMetadata({
+    producer: "pdf-merger-js based script",
+    author: "John Doe",
+    creator: "John Doe",
+    title: "My live as John Doe"
+  });
+
   await merger.save('merged.pdf'); //save under given name and reset the internal document
 
   // Export the merged PDF as a nodejs Buffer
@@ -55,7 +66,7 @@ The Browser version has the following export functions:
 * `setMetadata` set Metadata for producer, author, title or creator.
 * `reset` resets the internal state of the document, to start again.
 
-#### Sample - React
+#### async react example
 
 ```jsx
 import PDFMerger from 'pdf-merger-js/browser';
@@ -70,9 +81,13 @@ const Merger = (files) => {
       const merger = new PDFMerger();
 
       for(const file of files) {
-        await merger.add(file)
+        await merger.add(file);
       }
 
+      await merger.setMetadata({
+        producer: "pdf-merger-js based script"
+      });
+
       const mergedPdf = await merger.saveAsBlob();
       const url = URL.createObjectURL(mergedPdf);
 
@@ -99,27 +114,6 @@ const Merger = (files) => {
 };
 ```
 
-#### Sample - Set Metadata
-
-```js
-const merger = new PDFMerger();
-
-// Add files
-
-// Set only producer
-await merger.setMetadata({
-  producer: "Custom Producer",
-});
-
-// Set all 4 fields
-await merger.setMetadata({
-  producer: "Custom Producer",
-  author: "Custom Author",
-  creator: "Custom Creator",
-  title: "Custom Title"
-});
-```
-
 ## Similar libraries
 
 * [pdf-merge](https://www.npmjs.com/package/pdf-merge) has a dependency on [PDFtk](https://www.pdflabs.com/tools/pdftk-the-pdf-toolkit/).

browser.js

@@ -1,4 +1,4 @@
-const { PDFDocument } = require('pdf-lib')
+import { PDFDocument } from 'pdf-lib'
 
 const globalObject =
   typeof globalThis === 'object'
@@ -9,7 +9,7 @@ const globalObject =
         ? self // Worker
         : this
 
-class PDFMerger {
+export default class PDFMerger {
   constructor () {
     this.reset()
 
@@ -167,5 +167,3 @@ class PDFMerger {
     link.click()
   }
 }
-
-module.exports = PDFMerger

index.js

@@ -1,7 +1,7 @@
-const { PDFDocument } = require('pdf-lib')
-const fs = require('fs').promises
+import { PDFDocument } from 'pdf-lib'
+import fs from 'fs/promises'
 
-class PDFMerger {
+export default class PDFMerger {
   constructor () {
     this.reset()
 
@@ -122,5 +122,3 @@ class PDFMerger {
     return Buffer.from(uInt8Array)
   }
 }
-
-module.exports = PDFMerger

package.json

@@ -2,14 +2,18 @@
   "name": "pdf-merger-js",
   "version": "4.3.1",
   "description": "merge multiple PDF documents, or parts of them, to a new PDF document",
+  "type": "module",
+  "engines": {
+    "node": ">=14"
+  },
   "main": "./index.js",
   "types": "./index.d.ts",
   "browser": "./browser.js",
   "scripts": {
     "standard": "standard",
     "standard:fix": "standard --fix",
-    "test": "jest --detectOpenHandles",
-    "test:watch": "jest --watch --forceExit --detectOpenHandles"
+    "test": "node --experimental-vm-modules node_modules/jest/bin/jest --detectOpenHandles",
+    "test:watch": "node --experimental-vm-modules node_modules/jest/bin/jest.js --watch --forceExit --detectOpenHandles"
   },
   "standard": {
     "env": [

test/browser-fixtures.test.js

@@ -2,19 +2,22 @@
  * @jest-environment jsdom
  */
 
-const path = require('path')
-const fs = require('fs-extra')
-const pdfDiff = require('pdf-diff')
-const fetch = require('node-fetch')
+import path from 'path'
+import fs from 'fs-extra'
+import pdfDiff from 'pdf-diff'
+import fetch from 'node-fetch'
+import { jest } from '@jest/globals'
+
+import PDFMerger from '../browser'
+
 /*
   add a global `windows.fetch` to mock fetch
 */
 global.window.fetch = jest.fn().mockImplementation((requestUrl) => {
   return Promise.resolve(fetch(requestUrl))
 })
 
-const PDFMerger = require('../browser')
-
+const __dirname = path.dirname(new URL(import.meta.url).pathname)
 const FIXTURES_DIR = path.join(__dirname, 'fixtures')
 const TMP_DIR = path.join(__dirname, 'tmp')
 

test/fixtures.test.js

@@ -1,10 +1,12 @@
-const path = require('path')
-const fs = require('fs-extra')
-const pdfDiff = require('pdf-diff')
-const { PDFDocument } = require('pdf-lib')
+import path from 'path'
+import fs from 'fs-extra'
+import pdfDiff from 'pdf-diff'
+import { PDFDocument } from 'pdf-lib'
+import { jest } from '@jest/globals'
 
-const PDFMerger = require('../index')
+import PDFMerger from '../index'
 
+const __dirname = path.dirname(new URL(import.meta.url).pathname)
 const FIXTURES_DIR = path.join(__dirname, 'fixtures')
 const TMP_DIR = path.join(__dirname, 'tmp')
 

test/issues.test.js

@@ -1,8 +1,10 @@
-const path = require('path')
-const fs = require('fs-extra')
+import path from 'path'
+import fs from 'fs-extra'
+import { jest } from '@jest/globals'
 
-const PDFMerger = require('../index')
+import PDFMerger from '../index'
 
+const __dirname = path.dirname(new URL(import.meta.url).pathname)
 const FIXTURES_DIR = path.join(__dirname, 'fixtures')
 const TMP_DIR = path.join(__dirname, 'tmp')