Dreck OptiPNG Plugin

Compresses PNG files.

Dependencies

• OptiPNG

This must be available on the PATH (e.g. optipng --help prints help text when executed in a Bash terminal).

For running tests

If you wish to run tests, Imagemagick must be installed; convert must be available on the PATH (e.g. convert --help prints help text when executed in a Bash terminal).

Installing on Debian-based Linux distributions

OptiPNG is available from most Debian-based Linux distributions' package managers; for example, it can be installed when running Ubuntu 20.04 LTS using the following command:

sudo apt-get install optipng --yes

If you need to run tests, install Imagemagick:

sudo apt-get install imagemagick --yes

Installing within GitHub Actions

Add appropriate action steps to install OptiPNG before the make action step:

name: Continuous Integration
on: [push, pull_request]
jobs:
  main:
    runs-on: ubuntu-20.04
    steps:
    - uses: actions/checkout@v3
      with:
        submodules: true

    # Insert this block:
    ###############################
    - run: sudo apt-get install optipng --yes
      if: runner.os == 'Linux'
    - run: brew install optipng
      if: runner.os == 'macOS'
    ###############################

    - run: make --file ./submodules/dreck/makefile
      shell: bash
    - if: github.event_name == 'release' && github.event.action == 'created'
      uses: softprops/action-gh-release@v1
      with:
        files: dist/**

Installation

Run the following in a Bash shell at the root of your project:

git submodule add https://github.com/sunruse/dreck-optipng-plugin plugins/optipng

Input

This plugin compresses each PNG file in the DRECK_DATA_URI_INPUT_PNG_PATHS Make variable.

Output

This plugin writes an equivalent PNG document for each input PNG template. For example, if DRECK_DATA_URI_INPUT_PNG_PATHS contained ./a/b-c.png, ./plugins/optipng/generated/a/b-c.png would be written to disk.

Their paths are listed in the DRECK_DATA_URI_OUTPUT_PNG_PATHS Make variable, space separated.