The behaviour for implementing static file compressors.

Example

If you wanted to compress static files using an external brotli compression library, you could define a new module implementing the behaviour and add it to the list of configured compressors.

defmodule MyApp.Web.BrotliCompressor do
  @behaviour Combo.Static.Compressor

  def compress_file(file_path, content) do
    valid_extension = Path.extname(file_path) in Combo.Static.compressible_extensions()
    {:ok, compressed_content} = :brotli.encode(content)

    if valid_extension && byte_size(compressed_content) < byte_size(content) do
      {:ok, compressed_content}
    else
      :error
    end
  end

  def file_extensions do
    [".br"]
  end
end

# config/config.exs
config :combo, :static,
  compressors: [Combo.Static.Compressor.Gzip, MyApp.Web.BrotliCompressor],
  # ...