PDFium

Native bindings for pdfium project

Installing

• for Mix projects, add the following under deps in mix.exs:

    {:pdfium, "~> 0.1"}

• for single-file Elixir scripts, add the following:

    Mix.install([pdfium: "~> 0.1"])

Usage

1. open a PDF file descriptor:

   {:ok, document} = PDFium.load_document("file.pdf")
   # => {:ok, #Reference<0.2181297728.2193227786.166499>}

2. get the number of pages in the file:

   {:ok, pages} = PDFium.get_page_count(document)
   # => {:ok, 1}

3. render a page to file:

   {:ok, ref} = PDFium.load_document("/Users/eugene/Downloads/7ade6db09604a8b41104763c6f16a987.pdf")
   {:ok, binary, w, h} = PDFium.get_page_bitmap(ref, 0, 300) # 300 for DPI
   {:ok, image} = Vix.Vips.Image.new_from_binary(binary, w, h, 4, :VIPS_FORMAT_UCHAR)
   {:ok, _image} = Image.write(image, "/tmp/sample.png")

Releasing

1. bump version in VERSION file. Run:

   echo -n (awk 'BEGIN{FS=OFS="."} {$NF+=1}1' VERSION) > VERSION

2. commit and push the change:

   git add VERSION
   git commit --message "Bump library version"
   git push origin main

3. create a PR from main to stable. Run:

   gh pr create --base stable --fill

4. wait until the PR checks are green, then merge the PR

Running CI steps locally

1. Prepare:

   mkdir output

2. Build:

   dagger call \
     precompile --src-dir . --platform-name linux/arm64 --abi musl \
     export --path output/ --allowParentDirPath

3. Test:

   dagger call test \
     --precompiled output/pdfium-nif-2.17-aarch64-linux-musl-0.1.23.tar.gz \
     --abi musl --platform-name linux/arm64

Known issues

• Installing the library was tested and will work in macOS and inside Docker images built by Bob. Installing currently doesn't work under Elixir installed via package managers, such as via apk add elixir for example.

License

See [LICENSE].