File: mupdf_previewer.rb

package info (click to toggle)
rails 2%3A7.2.2.1%2Bdfsg-7
  • links: PTS, VCS
  • area: main
  • in suites: trixie
  • size: 43,352 kB
  • sloc: ruby: 349,799; javascript: 30,703; yacc: 46; sql: 43; sh: 29; makefile: 27
file content (40 lines) | stat: -rw-r--r-- 1,013 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
# frozen_string_literal: true

module ActiveStorage
  class Previewer::MuPDFPreviewer < Previewer
    class << self
      def accept?(blob)
        pdf?(blob.content_type) && mutool_exists?
      end

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

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

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

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

        @mutool_exists = $?.exitstatus == 1
      end
    end

    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

    private
      def draw_first_page_from(file, &block)
        draw self.class.mutool_path, "draw", "-F", "png", "-o", "-", file.path, "1", &block
      end
  end
end