Module: Metaclean::Exiftool

Defined in:
lib/metaclean/exiftool.rb

Constant Summary collapse

WRITE_UNSUPPORTED_RE = 
/
  writing\sof\s(?:this\stype\sof\s|[^\s]+\s)?files?\sis\snot\s(?:yet\s)?supported |
  can't\scurrently\swrite |
  does\snot\syet\ssupport\swriting
/ix
PRESERVE_TAGS = 
%w[Orientation ICC_Profile].freeze

Class Method Summary collapse

Class Method Details

.available? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/metaclean/exiftool.rb', line 9

def available?
  return @available if defined?(@available)

  out, _err, status = Metaclean.capture3(
    'exiftool', '-ver',
    timeout: Metaclean::PROBE_TIMEOUT,
    max_output: Metaclean::PROBE_MAX_OUTPUT_BYTES
  )
  @available = status.success?
  @version = @available ? out.strip : nil
  @available
rescue Errno::ENOENT, Error
  @version = nil
  @available = false
end

.read(path) ⇒ Object 



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# File 'lib/metaclean/exiftool.rb', line 29

def read(path)
  out, err, status = Metaclean.capture3(
    'exiftool', '-j', '-G1', '-a', '-u', '-s', '-n', '-api', 'largefilesupport=1',
    Metaclean.safe_path(path)
  )
  raise Error, "ExifTool read failed: #{read_error_detail(out, err)}" unless status.success?

  data = JSON.parse(out)
  raise Error, 'Unexpected ExifTool output (expected a JSON array)' unless data.is_a?(Array)

  scrub_encoding(data.first || {})
rescue JSON::ParserError => e
  raise Error, "Could not parse ExifTool output: #{e.message}"
end

.read_error_detail(out, err) ⇒ Object 



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# File 'lib/metaclean/exiftool.rb', line 44

def read_error_detail(out, err)
  return err.strip unless err.strip.empty?

  data = JSON.parse(out)
  entry = data.is_a?(Array) ? data.first : nil
  detail = entry && (entry['ExifTool:Error'] || entry['Error'])
  detail ? detail.to_s.strip : 'unknown error'
rescue JSON::ParserError
  'unknown error'
end

.scrub_encoding(obj) ⇒ Object 



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# File 'lib/metaclean/exiftool.rb', line 55

def scrub_encoding(obj)
  case obj
  when String then obj.valid_encoding? ? obj : obj.scrub
  when Array  then obj.map { |e| scrub_encoding(e) }
  when Hash   then obj.transform_values { |v| scrub_encoding(v) }
  else obj
  end
end

.strip!(path, also_delete: []) ⇒ Object

Raises:



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# File 'lib/metaclean/exiftool.rb', line 72

def strip!(path, also_delete: [])
  FileOps.regular_stat!(path)
  args = ['exiftool', '-all=', '-gps:all=']
  also_delete.each { |tag| args << "-#{tag}=" }
  args.concat(['-tagsfromfile', '@'])
  PRESERVE_TAGS.each { |tag| args << "-#{tag}" }
  args.concat(['-overwrite_original', '-q', '-q', '-api', 'largefilesupport=1', Metaclean.safe_path(path)])

  _out, err, status = Metaclean.capture3(*args)
  if status.success?
    FileOps.validate_output!(path)
    return true
  end
  return :unsupported if err.match?(WRITE_UNSUPPORTED_RE)

  raise Error, "ExifTool strip failed: #{err.strip}"
end

.version ⇒ Object 



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# File 'lib/metaclean/exiftool.rb', line 25

def version
  available? ? @version : nil
end