Jonas Jenwald 3a372fde94 [api-minor] Replace the CMapReaderFactory, StandardFontDataFactory, and WasmFactory API options with a single factory/option
Currently we have no less than three different, but very similar, factories for reading built-in CMap files, standard font files, and wasm files on the main-thread.[1]
These factories were added at different points in time, since I cannot imagine that we'd add essentially three copies of the same code otherwise.

Nowadays these factories are often not even used[2], since worker-thread fetching is used whenever possible to improve performance. In particular, they will *only* be used when either:
 - The PDF.js library runs in Node.js environments.
 - The user manually sets `useWorkerFetch = false` when calling `getDocument`.
 - The user provides custom `CMapReaderFactory`, `StandardFontDataFactory`, and/or `WasmFactory` instances when calling `getDocument`.

By replacing these factories with *a single* new `BinaryDataFactory` factory/option the number of `getDocument` options are thus reduced, which cannot hurt.
This also reduces the total bundle-size of the Firefox PDF Viewer a little bit, and it slightly reduces the number of import maps that need to be maintained.

*Please note:* For users that provide custom `CMapReaderFactory`, `StandardFontDataFactory`, and `WasmFactory` instances when calling `getDocument` this will be a breaking change, however it's unlikely that (many) such users exist.
(The *internal* format data-format of `CMapReaderFactory` was changed in PR 18951, and there hasn't been a single question/complaint about it in well over a year.)

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[1] Any new functionality could easily lead to more such factories being added in the future, which wouldn't be great.

[2] Note that the Firefox PDF Viewer no longer use these factories, since it "forcibly" sets `useWorkerFetch = true` during building.
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PDF.js is a Portable Document Format (PDF) viewer that is built with HTML5.

PDF.js is community-driven and supported by Mozilla. Our goal is to create a general-purpose, web standards-based platform for parsing and rendering PDFs.

Contributing

PDF.js is an open source project and always looking for more contributors. To get involved, visit:

Feel free to stop by our Matrix room for questions or guidance.

Getting Started

Online demo

Please note that the "Modern browsers" version assumes native support for the latest JavaScript features; please also see this wiki page.

Browser Extensions

Firefox

PDF.js is built into version 19+ of Firefox.

Chrome

  • The official extension for Chrome can be installed from the Chrome Web Store. This extension is maintained by @Rob--W.
  • Build Your Own - Get the code as explained below and issue npx gulp chromium. Then open Chrome, go to Tools > Extension and load the (unpackaged) extension from the directory build/chromium.

PDF debugger

Browser the internal structure of a PDF document with https://mozilla.github.io/pdf.js/internal-viewer/web/debugger.html

Getting the Code

To get a local copy of the current code, clone it using git:

$ git clone https://github.com/mozilla/pdf.js.git
$ cd pdf.js

Next, install Node.js via the official package or via nvm. If everything worked out, install all dependencies for PDF.js:

$ npm install

Finally, you need to start a local web server as some browsers do not allow opening PDF files using a file:// URL. Run:

$ npx gulp server

and then you can open:

Please keep in mind that this assumes the latest version of Mozilla Firefox; refer to Building PDF.js for non-development usage of the PDF.js library.

It is also possible to view all test PDF files on the right side by opening:

Building PDF.js

In order to bundle all src/ files into two production scripts and build the generic viewer, run:

$ npx gulp generic

If you need to support older browsers, run:

$ npx gulp generic-legacy

This will generate pdf.js and pdf.worker.js in the build/generic/build/ directory (respectively build/generic-legacy/build/). Both scripts are needed but only pdf.js needs to be included since pdf.worker.js will be loaded by pdf.js. The PDF.js files are large and should be minified for production.

Using PDF.js in a web application

To use PDF.js in a web application you can choose to use a pre-built version of the library or to build it from source. We supply pre-built versions for usage with NPM under the pdfjs-dist name. For more information and examples please refer to the wiki page on this subject.

Including via a CDN

PDF.js is hosted on several free CDNs:

Learning

You can play with the PDF.js API directly from your browser using the live demos below:

More examples can be found in the examples folder. Some of them are using the pdfjs-dist package, which can be built and installed in this repo directory via npx gulp dist-install command.

For an introduction to the PDF.js code, check out the presentation by our contributor Julian Viereck:

More learning resources can be found at:

The API documentation can be found at:

Questions

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PDF Reader in JavaScript
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