Class: ActiveStorage::Previewer::PopplerPDFPreviewer

Inherits:
ActiveStorage::Previewer show all
Defined in:
lib/active_storage/previewer/poppler_pdf_previewer.rb

Instance Attribute Summary

Attributes inherited from ActiveStorage::Previewer

#blob

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from ActiveStorage::Previewer

#initialize

Constructor Details

This class inherits a constructor from ActiveStorage::Previewer

Class Method Details

.accept?(blob) ⇒ Boolean

Returns:

  • (Boolean) 


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

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

.pdf?(content_type) ⇒ Boolean

Returns:

  • (Boolean) 


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

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

.pdftoppm_exists? ⇒ Boolean

Returns:

  • (Boolean) 


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

def pdftoppm_exists?
  return @pdftoppm_exists unless @pdftoppm_exists.nil?

  @pdftoppm_exists = system(pdftoppm_path, "-v", out: File::NULL, err: File::NULL)
end

.pdftoppm_path ⇒ Object 



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

def pdftoppm_path
  ActiveStorage.paths[:pdftoppm] || "pdftoppm"
end

Instance Method Details

#preview(**options) ⇒ Object 



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# File 'lib/active_storage/previewer/poppler_pdf_previewer.rb', line 25

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