Class: Rbpptx::Presentation

Inherits:
Object
  • Object
show all
Defined in:
lib/rbpptx/presentation.rb

Overview

A PowerPoint presentation loaded from a .pptx file.

Reading is the only mode wired up at present: the package is opened, the presentation part is located via _rels/.rels, the slide id list is read in document order, and slides are resolved through the presentation’s own rels. Each Slide retains a handle on the underlying ZIP and parses its XML lazily.

Constant Summary collapse

P_NS = 
"http://schemas.openxmlformats.org/presentationml/2006/main".freeze
A_NS = 
"http://schemas.openxmlformats.org/drawingml/2006/main".freeze
R_NS = 
"http://schemas.openxmlformats.org/officeDocument/2006/relationships".freeze
PKG_REL_NS = 
"http://schemas.openxmlformats.org/package/2006/relationships".freeze
OFFICE_DOC_REL_TYPE = 
"http://schemas.openxmlformats.org/officeDocument/2006/relationships/officeDocument".freeze
SLIDE_REL_TYPE = 
"http://schemas.openxmlformats.org/officeDocument/2006/relationships/slide".freeze
LEGACY_PPT_SIGNATURE = 
"\xD0\xCF\x11\xE0\xA1\xB1\x1A\xE1".b.freeze
ZIP_SIGNATURE = 
"PK\x03\x04".b.freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(path) ⇒ Presentation

Returns a new instance of Presentation.



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# File 'lib/rbpptx/presentation.rb', line 29

def initialize(path)
  @path = path.to_s
  @closed = false
  validate_signature!
  begin
    @zip = Zip::File.open(@path)
  rescue Zip::Error => e
    raise UnsupportedFormatError, "#{@path}: not a valid .pptx (#{e.message})"
  end
end

Instance Attribute Details

#path ⇒ String (readonly)

Returns absolute path the presentation was loaded from.

Returns:

  • (String) —

    absolute path the presentation was loaded from



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# File 'lib/rbpptx/presentation.rb', line 21

def path
  @path
end

Class Method Details

.open(path) ⇒ Object

Opens an existing presentation. See Rbpptx.open for the public entry point that supports the block-with-auto-close idiom.



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# File 'lib/rbpptx/presentation.rb', line 25

def self.open(path)
  new(path)
end

Instance Method Details

#close ⇒ Boolean

Releases the underlying ZIP file. Idempotent.

Returns:

  • (Boolean) —

    true on the first call, false on subsequent calls



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# File 'lib/rbpptx/presentation.rb', line 94

def close
  return false if @closed

  @zip&.close
  @zip = nil
  @closed = true
  true
end

#closed? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rbpptx/presentation.rb', line 104

def closed?
  @closed
end

#save(path) ⇒ String

Writes the presentation out to path, preserving every part that has not been mutated byte-for-byte. Slides whose shapes have been edited are re-serialized from their in-memory Nokogiri document; all other entries (themes, masters, layouts, media, fonts, rels) are streamed straight from the source ZIP without re-parsing, so unknown PowerPoint features round-trip unchanged.

path may equal the original load path; the new file is written to a temp file in the same directory and atomically renamed into place. On success, dirty flags on each slide are cleared.

Parameters:

  • path (String, #to_path)

Returns:

  • (String) —

    the path that was written



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# File 'lib/rbpptx/presentation.rb', line 60

def save(path)
  ensure_open!
  out_path = path.to_s
  overrides = (@slides || []).each_with_object({}) do |slide, h|
    h[slide.part_name] = slide.to_xml if slide.dirty?
  end

  tmp_path = "#{out_path}.rbpptx-tmp.#{Process.pid}.#{rand(1 << 32).to_s(16)}"
  begin
    Zip::OutputStream.open(tmp_path) do |out|
      @zip.each do |entry|
        next if entry.directory?

        if (override_xml = overrides[entry.name])
          out.put_next_entry(entry.name)
          out.write(override_xml)
        else
          out.copy_raw_entry(entry)
        end
      end
    end
    File.rename(tmp_path, out_path)
  rescue StandardError
    File.unlink(tmp_path) if File.exist?(tmp_path)
    raise
  end

  (@slides || []).each(&:clear_dirty!)
  out_path
end

#slides ⇒ Array<Slide>

Returns slides in presentation order (matches the order of <p:sldId> entries inside ppt/presentation.xml).

Returns:

  • (Array<Slide>) —

    slides in presentation order (matches the order of <p:sldId> entries inside ppt/presentation.xml)



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# File 'lib/rbpptx/presentation.rb', line 42

def slides
  ensure_open!
  @slides ||= build_slides
end