Class: ActiveStorage::Previewer::MuPDFPreviewer

Inherits:
Previewer
  • Object
show all
Defined in:
lib/active_storage/previewer/mupdf_previewer.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.accept?(blob) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_storage/previewer/mupdf_previewer.rb', line 6

def accept?(blob)
  pdf?(blob.content_type) && mutool_exists?
end

.mutool_exists? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_storage/previewer/mupdf_previewer.rb', line 18

def mutool_exists?
  return @mutool_exists unless @mutool_exists.nil?

  system mutool_path, out: File::NULL, err: File::NULL

  @mutool_exists = $?.exitstatus == 1
end

.mutool_path ⇒ Object 



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# File 'lib/active_storage/previewer/mupdf_previewer.rb', line 14

def mutool_path
  ActiveStorage.paths[:mutool] || "mutool"
end

.pdf?(content_type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/active_storage/previewer/mupdf_previewer.rb', line 10

def pdf?(content_type)
  Marcel::Magic.child? content_type, "application/pdf"
end

Instance Method Details

#preview(**options) ⇒ Object 



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# File 'lib/active_storage/previewer/mupdf_previewer.rb', line 27

def preview(**options)
  download_blob_to_tempfile do |input|
    draw_first_page_from input do |output|
      yield io: output, filename: "#{blob.filename.base}.png", content_type: "image/png", **options
    end
  end
end