PhoenixBakery

Better compression for your Phoenix assets.

This is set of modules that implement Phoenix.Digester.Compressor behaviour which can be used together with Phoenix 1.6 or later for better compression of the static assets served by Plug.Static.

Installation

First thing to do is to add PhoenixBakery as a dependency.

def deps do
  [
    {:phoenix_bakery, "~> 0.1.0", runtime: false}
  ]
end

And configure your Plug.Static:

plug Plug.Static,
  encodings: [{"zstd", ".zstd"}],
  gzip: true,
  brotli: true,
  # Rest of the options…

WARNING: Current release of Plug (1.12.1) do not support :encodings option yet and this option is ignored. So Zstandard-compressed files will not be served to the clients, even if client will have support for such format. Future releases of Plug however should make it work as expected. See elixir-plug/plug#1050.

Then you need to configure your compressors via Phoenix configuration:

config :phoenix,
  static_compressors: [
    # Pick all that you want to use
    PhoenixBakery.Gzip,
    PhoenixBakery.Brotli,
    PhoenixBakery.Zstd
  ]

Supported compressors

PhoenixBakery.Gzip

Replacement of default Phoenix.Digester.Gzip that provides better default compression ratio (defaults to maximum possible) instead of default option that compromises between compression speed and compression ratio.

It uses built-in zlib library, which mean, that there is no external dependencies and it will work OotB on any installation.

Configuration

PhoenixBakery.Gzip provides 3 different knobs that you can alter via application configuration:

config :phoenix_bakery, :gzip_opts, %{
    level: :best_speed, # defaults to: `:best_compression`
    window_bits: 8, # defaults to: `15` (max)
    mem_level: 8 # defaults to: `9` (max)
  }

The shown above are defaults. For description of each option check zlib documentaion

PhoenixBakery.Brotli

Brotli is algorithm that offers better compression ratio when compared with Gzip, but at the cost of greater memory consumption during compression. It provides quite good decompression speed. It is supported by all major modern browsers

Requirements

To use PhoenixBakery.Brotli you need at least one of:

• Add {:brotli, ">= 0.0.0", runtime: false} to use NIF version of the Brotli compressor. It requires C code compilation and it can slow down compilation a little as the compilation isn't the fastest.
• Have brotli utility available in $PATH or configured via config :phoenix_bakery, :brotli, "/path/to/brotli"

If none of the above is true then compressor will raise.

Configuration

config :phoenix_bakery,
  brotli_opts: %{
    quality: 5 # defaults to: `11` (max)
  }

PhoenixBakery.Zstd

Zstandard is algorithm that offers quite good compression ratio when compared with Gzip, but slightly worse than Brotli, but with much betted decompression speed. It is currently not supported by browsers, but is already IANA standard, so the rollout of the support should be pretty fast.

Requirements

To use PhoenixBakery.Zstd you need at least one of:

• Add {:ezstd, "~> 1.0", runtime: false} to use NIF version of Zstd compressor. It requires C code compilation and git tool to be available to fetch the code of zstandard code.
• Have zstd utility available in $PATH or configured via config :phoenix_bakery, :zstd, "<path-to-zstd-executable>/zstd"

If none of the above is true then compressor will raise.

Configuration

config :phoenix_bakery,
  zstd_opts: %{
    level: 10 # defaults to: `22` (ultra-max)
  }