Class: HtmlTo::ImageGenerate

Inherits:
Object
  • Object
show all
Includes:
Chromium
Defined in:
lib/html_to/image_generate.rb

Instance Method Summary collapse

Methods included from Chromium

execute_path, version

Instance Method Details

#attach_image(record, image_name) ⇒ Object 



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# File 'lib/html_to/image_generate.rb', line 41

def attach_image(record, image_name)
  record.html_to_skip_meta_image_generate = true
  record.send(image_name).purge
  record.send(image_name).attach(io: optimize_screenshot, filename: optimize_screenshot, content_type: 'image/png')
  return unless optimize_screenshot

  optimize_screenshot.close
end

#call(record, serializer, options) ⇒ Object 



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# File 'lib/html_to/image_generate.rb', line 7

def call(record, serializer, options)
  generate_template(record, serializer, options[:template], options[:width], options[:height])
  take_screenshot(options[:width], options[:height])
  attach_image(record, options[:image_name])
rescue StandardError
  raise
ensure
  FileUtils.rm_f(html_file_path)
  FileUtils.rm_f(optimize_screenshot) if optimize_screenshot
  FileUtils.rm_f(screenshot_file_path)
end

#generate_template(record, serializer, template, width, height) ⇒ Object 



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# File 'lib/html_to/image_generate.rb', line 19

def generate_template(record, serializer, template, width, height)
  object = serializer.constantize.new(record)
  html = File.open(template) do |f|
    ERB.new(f.read).result(binding)
  end
  File.write(html_file_path, html)
end

#html_file_path ⇒ Object 



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# File 'lib/html_to/image_generate.rb', line 50

def html_file_path
  @html_file_path ||= Rails.root.join('tmp').join("#{SecureRandom.urlsafe_base64.downcase}.html")
end

#optimize_screenshot ⇒ Object 



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# File 'lib/html_to/image_generate.rb', line 58

def optimize_screenshot
  return nil unless File.exist?(screenshot_file_path)

  @optimize_screenshot ||= if image_processing_installed?
                             ImageProcessing::MiniMagick
                               .source(screenshot_file_path)
                               .convert('jpg')
                               .saver(quality: 85)
                               .call
                           else
                             File.open(screenshot_file_path)
                           end
end

#screenshot_file_path ⇒ Object 



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# File 'lib/html_to/image_generate.rb', line 54

def screenshot_file_path
  @screenshot_file_path ||= Rails.root.join('tmp').join("#{SecureRandom.urlsafe_base64.downcase}.png")
end

#take_screenshot(width, height) ⇒ Object

Raises:

  • (StandardError) 


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# File 'lib/html_to/image_generate.rb', line 27

def take_screenshot(width, height)
  cmd = "    \#{HtmlTo::Chromium.execute_path.shellescape} \\\n    --headless \\\n    --screenshot=\#{screenshot_file_path} \\\n    --window-size=\#{width},\#{height} \\\n    --disable-gpu \\\n    --disable-features=NetworkService \#{html_file_path}\n  BASH\n\n  %x(\#{cmd})\n  raise StandardError, \"html_to error result = \#{$CHILD_STATUS}; command = \#{cmd}\" unless chromium_run_success?\nend\n".chomp