Class: Configuration::Thumbnail

Inherits:

Object

• Object
• Configuration::Thumbnail

Extended by:

Stats

Includes:

ClassLogging, ConditionalInclusion

Defined in:

lib/httpimagestore/configuration/thumbnailer.rb

Defined Under Namespace

Classes: ThumbnailSpec, ThumbnailingError

Class Method Summary

• .match(node) ⇒ Object
• .parse(configuration, node) ⇒ Object

Instance Method Summary

• #initialize(global, source_image_name, specs, use_multipart_api, matcher) ⇒ Thumbnail constructor

  A new instance of Thumbnail.

• #realize(request_state) ⇒ Object

Methods included from ConditionalInclusion

#excluded?, #included?, #inclusion_matcher

Constructor Details

#initialize(global, source_image_name, specs, use_multipart_api, matcher) ⇒ Thumbnail

Returns a new instance of Thumbnail.

# File 'lib/httpimagestore/configuration/thumbnailer.rb', line 145

def initialize(global, source_image_name, specs, use_multipart_api, matcher)
  @global = global
  @source_image_name = source_image_name
  @specs = specs
  @use_multipart_api = use_multipart_api
  inclusion_matcher matcher
end

Class Method Details

.match(node) ⇒ Object

# File 'lib/httpimagestore/configuration/thumbnailer.rb', line 99

def self.match(node)
  node.name == 'thumbnail'
end

.parse(configuration, node) ⇒ Object

# File 'lib/httpimagestore/configuration/thumbnailer.rb', line 103

def self.parse(configuration, node)
  use_multipart_api = node.values.length == 1 ? true : false

  nodes = use_multipart_api ?  node.children : [node]
  source_image_name = use_multipart_api ? node.grab_values('source image name').first : nil # parsed later

  nodes.empty? and raise NoValueError.new(node, 'thumbnail image name')
  matcher = nil

  specs = nodes.map do |node|
    if use_multipart_api
      image_name = node.grab_values('thumbnail image name').first
    else
      source_image_name, image_name = *node.grab_values('source image name', 'thumbnail image name')
    end

    operation, width, height, format, if_image_name_on, remaining = *node.grab_attributes_with_remaining('operation', 'width', 'height', 'format', 'if-image-name-on')

    matcher = InclusionMatcher.new(image_name, if_image_name_on) if if_image_name_on

    ThumbnailSpec.new(
      image_name,
      operation || 'fit',
      width || 'input',
      height || 'input',
      format || 'input',
      remaining || {},
      matcher
    )
  end

  matcher = InclusionMatcher.new(source_image_name, node.grab_attributes('if-image-name-on').first) if use_multipart_api

  configuration.processors << self.new(
    configuration.global,
    source_image_name,
    specs,
    use_multipart_api,
    matcher
  )
end

Instance Method Details

#realize(request_state) ⇒ Object

# File 'lib/httpimagestore/configuration/thumbnailer.rb', line 153

def realize(request_state)
  client = @global.thumbnailer or fail 'thumbnailer configuration'

  rendered_specs = {}
  @specs.select do |spec|
    spec.included?(request_state)
  end.each do |spec|
    rendered_specs.merge! spec.render(request_state)
  end
  source_image = request_state.images[@source_image_name]

  thumbnails = {}
  input_mime_type = nil
  input_width = nil
  input_height = nil

  Thumbnail.stats.incr_total_thumbnail_requests
  Thumbnail.stats.incr_total_thumbnail_requests_bytes source_image.data.bytesize

  if @use_multipart_api
    log.info "thumbnailing '#{@source_image_name}' to multiple specs: #{rendered_specs}"

    # need to reference to local so they are available within thumbnail() block context
    source_image_name = @source_image_name
    logger = log

    begin
      thumbnails = client.with_headers(request_state.headers).thumbnail(source_image.data) do
        rendered_specs.each_pair do |name, spec|
          begin
            thumbnail(*spec)
          rescue HTTPThumbnailerClient::HTTPThumbnailerClientError => error
            logger.warn 'got thumbnailer error while passing specs', error
            raise ThumbnailingError.new(source_image_name, name, error)
          end
        end
      end
    rescue HTTPThumbnailerClient::HTTPThumbnailerClientError => error
      logger.warn 'got thumbnailer error while sending input data', error
      raise ThumbnailingError.new(source_image_name, nil, error)
    end

    input_mime_type = thumbnails.input_mime_type
    input_width = thumbnails.input_width
    input_height = thumbnails.input_height

    # check each thumbnail for errors
    thumbnails = Hash[rendered_specs.keys.zip(thumbnails)]
    thumbnails.each do |name, thumbnail|
      if thumbnail.kind_of? HTTPThumbnailerClient::HTTPThumbnailerClientError
        error = thumbnail
        log.warn 'got single thumbnail error', error
        raise ThumbnailingError.new(@source_image_name, name, error)
      end
    end

    # borrow from memory limit - note that we might have already used too much memory
    thumbnails.each do |name, thumbnail|
      request_state.memory_limit.borrow(thumbnail.data.bytesize, "thumbnail '#{name}'")
    end
  else
    name, rendered_spec = *rendered_specs.first
    log.info "thumbnailing '#{@source_image_name}' to '#{name}' with spec: #{rendered_spec}"

    begin
      thumbnail = client.with_headers(request_state.headers).thumbnail(source_image.data, *rendered_spec)
      request_state.memory_limit.borrow(thumbnail.data.bytesize, "thumbnail '#{name}'")

      input_mime_type = thumbnail.input_mime_type
      input_width = thumbnail.input_width
      input_height = thumbnail.input_height

      thumbnails[name] = thumbnail
    rescue HTTPThumbnailerClient::HTTPThumbnailerClientError => error
      log.warn 'got thumbnailer error', error
      raise ThumbnailingError.new(@source_image_name, name, error)
    end
  end

  # copy input source path and url
  thumbnails.each do |name, thumbnail|
    thumbnail.extend ImageMetaData
    thumbnail.source_path = source_image.source_path
    thumbnail.source_url = source_image.source_url

    Thumbnail.stats.incr_total_thumbnail_thumbnails
    Thumbnail.stats.incr_total_thumbnail_thumbnails_bytes thumbnail.data.bytesize
  end

  # use httpthumbnailer provided information on input image mime type and size
  source_image.mime_type = input_mime_type if input_mime_type
  source_image.width = input_width if input_width
  source_image.height = input_height if input_height

  request_state.images.merge! thumbnails
end