https://github.com/zentered/rust-pdf-to-png-service
Pdf to Png conversion service in Rust
https://github.com/zentered/rust-pdf-to-png-service
libvips pdf-converter pdf-to-png pdfium rust
Last synced: 2 months ago
JSON representation
Pdf to Png conversion service in Rust
- Host: GitHub
- URL: https://github.com/zentered/rust-pdf-to-png-service
- Owner: zentered
- License: mit
- Created: 2023-02-22T07:38:51.000Z (over 2 years ago)
- Default Branch: main
- Last Pushed: 2023-02-22T08:06:05.000Z (over 2 years ago)
- Last Synced: 2025-04-01T15:58:40.332Z (3 months ago)
- Topics: libvips, pdf-converter, pdf-to-png, pdfium, rust
- Language: Rust
- Homepage:
- Size: 8.32 MB
- Stars: 22
- Watchers: 1
- Forks: 2
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
Awesome Lists containing this project
README
# PDF to PNG Service
This is the result of a long, painful and embarrassing journey to resolve a very
simple task: get pngs and webp files from a PDF. Here are a few alternatives we
tried:
- [pdf-to-png-converter](https://www.npmjs.com/package/pdf-to-png-converter) -
great, simple solution, but limited pdf render functions
- [gm](https://www.npmjs.com/package/gm) - tried many different variations but
we couldn't get this to work
- [sharp](https://sharp.pixelplumbing.com) - built on `libvips` it's the fastest
image conversion library, but doesn't come with PDF support out of the box.
`pdfium` is required and it's a nightmare to try to build a somewhat
up-to-date Dockerfile with `libvips` and `libpdfium`.
Cloud Functions / Lambda have ImageMagick pre-installed which should be
capbable, but:
- on Google Cloud Functions, ImageMagick is only installed on the Node 12 and 14
runtime. Not on Node 16 :facepalm:
- In order to read PDF, ImageMagick requires a change in a `policy.xml` which we
don't have access to in the Functions environment
## Setup
The `Dockerfile` has everything you need. You can build it locally or in the
cloud and use the Cloud Run environment to start the container. There are two
environment variables needed:
```
SOURCE_BUCKET=source-bucket
DEST_BUCKET=destination-bucket
```
This service is currently designed for Google Cloud
[EventArc](https://cloud.google.com/eventarc/docs/) triggers. You should create
a trigger on the source bucket when new files are uploaded/finalized. The
trigger will then call the Cloud Run instance and execute this service. There'll
be various versions:
- original png: full size, 90% quality
- preview png: 1920px width, 75% quality, interlace
- thumbnail png: 1024px width, 70% quality, interlace
- lossless webp: full size, 100% quality
- preview webp: 1920px width, 75% quality
All versions will be stored on the destination bucket with the same filename as
the source (including folders), and a prefix for the version.
### Local Development
To build and run locally, you need to create a service account and place the
keyfile in the same folder. You'll need to add:
```
GOOGLE_APPLICATION_CREDENTIALS=keyfile.json
```
As an environment variable. `vips` is linked statically:
```
RUSTFLAGS="-C target-feature=-crt-static $(pkg-config vips --libs)" cargo build && ./target/debug/pdf-service
```
Feel free to fork to adjust this to your own needs.
**Happy converting.**
## Acknowledgements & Thanks
- [Federico Rampazzo](https://github.com/framp) for the help with Rust and
putting the libraries together.
- [Lachezar Lechev](https://github.com/elpiel) for the final touches and getting
the http wrapper to work.
- [Naohiro Yoshida](https://github.com/yoshidan) for the Google Cloud libraries
in Rust
## License
Licensed under [MIT](./LICENSE).
Built with :love_letter: in Cyprus :cyprus: