Class: CombinePDF::PDF

Inherits:
Object
  • Object
show all
Defined in:
lib/combine_pdf/combine_pdf_pdf.rb

Overview

PDF class is the PDF object that can save itself to a file and that can be used as a container for a full PDF file data, including version etc’.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ PDF

Returns a new instance of PDF.



17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 17

def initialize (*args)
  # default before setting
  @objects = []
  @version = 0 
  @info = {}
  if args[0].is_a? PDFParser
    @objects = args[0].parse
    @version = args[0].version if args[0].version.is_a? Float
    @info = args[0].info_object || {}
  elsif args[0].is_a? Array
    # object initialization
    @objects = args[0]
    @version = args[1] if args[1].is_a? Float
  elsif args[0].is_a? Hash
    @objects = args
  end
  # connecting references with original objects
  serialize_objects_and_references
  # general globals
  @string_output = :literal
  @need_to_rebuild_resources = false
  @set_start_id = 1
  @info[:Producer] = "Ruby CombinePDF Library by Boaz Segev"
  @info.delete :CreationDate
  @info.delete :ModDate
  warn "finished to initialize PDF object."
end

Instance Attribute Details

#info ⇒ Object (readonly)

Returns the value of attribute info.



14
15
16
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 14

def info
  @info
end

#objects ⇒ Object (readonly)

Returns the value of attribute objects.



14
15
16
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 14

def objects
  @objects
end

#string_output ⇒ Object

Returns the value of attribute string_output.



15
16
17
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 15

def string_output
  @string_output
end

#version ⇒ Object

Returns the value of attribute version.



16
17
18
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 16

def version
  @version
end

Instance Method Details

#<<(obj) ⇒ Object

this function adds pages or CombinePDF objects at the end of the file (merge) for example:

pdf = CombinePDF.new "first_file.pdf"
pdf << CombinePDF.new "second_file.pdf"
pdf.save "both_files_merged.pdf"



153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 153

def << (obj)
  #########
  ## how should we add data to PDF?
  ## and how to handles imported pages?
  case
   when (obj.is_a?(PDF))
    @version = [@version, obj.version].max

    obj.renumber_object_ids @set_start_id + @objects.length

    @objects.push(*obj.objects)
    # rebuild_catalog
    @need_to_rebuild_resources = true
   when (obj.is_a?(Hash) && obj[:Type] == :Page), (obj.is_a?(Array) && (obj.reject {|i| i.is_a?(Hash) && i[:Type] == :Page}).empty?)
     # set obj paramater to array if it's only one page
     obj = [obj] if obj.is_a?(Hash)
    # add page(s) to objects
    @objects.push(*obj)
    # add page dependencies to objects
    add_referenced(obj)
    # add page(s) to Catalog(s)
    rebuild_catalog obj
    @need_to_rebuild_resources = true
  when (obj.is_a?(Hash) && obj[:indirect_reference_id] && obj[:referenced_object].nil?)
    #only let top level indirect objects into the PDF tree.
    @objects << obj
    @need_to_rebuild_resources = true
  else
    warn "Shouldn't add objects to the file if they are not top-level indirect PDF objects."
  end
end

#add_referenced(object) ⇒ Object 



264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 264

def add_referenced(object)
  # add references but not root
  case 
  when object.is_a?(Array)
    object.each {|it| add_referenced(it)}
  when object.is_a?(Hash)
    if object[:is_reference_only] && object[:referenced_object]
      unless @objects.include? object[:referenced_object]
        @objects << object[:referenced_object]
        object[:referenced_object].each do |k, v|
          add_referenced(v) unless k == :Parent
        end           
      end
    else
      object.each do |k, v|
        add_referenced(v) unless k == :Parent 
      end
    end
  end
end

#all_indirect_object ⇒ Object 



252
253
254
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 252

def all_indirect_object
  [].tap {|out| @objects.each {|obj| out << obj if (obj.is_a?(Hash) && obj[:is_reference_only].nil?) } }
end

#all_pages ⇒ Object

this function returns all the Page objects - regardless of order and even if not cataloged could be used for finding “lost” pages… but actually rather useless.



141
142
143
144
145
146
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 141

def all_pages
  #########
  ## Only return the page item, but make sure all references are connected so that
  ## referenced items and be reached through the connections.
  [].tap {|out|  each_object {|obj| out << obj  if obj.is_a?(Hash) && obj[:Type] == :Page }  }
end

#compare_reference_values(obj, ref) ⇒ Object

the function rerturns true if the reference belongs to the object



381
382
383
384
385
386
387
388
389
390
391
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 381

def compare_reference_values(obj, ref)
  if obj[:referenced_object] && ref[:referenced_object]
    return (obj[:referenced_object][:indirect_reference_id] == ref[:referenced_object][:indirect_reference_id] && obj[:referenced_object][:indirect_generation_number] == ref[:referenced_object][:indirect_generation_number])
  elsif ref[:referenced_object]
    return (obj[:indirect_reference_id] == ref[:referenced_object][:indirect_reference_id] && obj[:indirect_generation_number] == ref[:referenced_object][:indirect_generation_number])
  elsif obj[:referenced_object]
    return (obj[:referenced_object][:indirect_reference_id] == ref[:indirect_reference_id] && obj[:referenced_object][:indirect_generation_number] == ref[:indirect_generation_number])
  else
    return (obj[:indirect_reference_id] == ref[:indirect_reference_id] && obj[:indirect_generation_number] == ref[:indirect_generation_number])
  end
end

#each_object(&block) ⇒ Object

run block of code on evey object (Hash)



377
378
379
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 377

def each_object(&block)
  PDFOperations._each_object(@objects, &block)
end

#pages(catalogs = nil) ⇒ Object

this function returns all the pages cataloged in the catalog. if no catalog is passed, it seeks the existing catalog(s) and searches for any registered Page objects.



102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 102

def pages(catalogs = nil)
  page_list = []
  if catalogs == nil
    catalogs = @objects.select {|obj| obj.is_a?(Hash) && obj[:Type] == :Catalog}
    catalogs ||= []
  end
  case 
  when catalogs.is_a?(Array)
    catalogs.each {|c| page_list.push *(pages(c)) unless c.nil?}
  when catalogs.is_a?(Hash)
    if catalogs[:is_reference_only]
      catalogs[:referenced_object] = pages(PDFOperations.get_refernced_object @objects, catalogs) unless catalogs[:referenced_object]
      if catalogs[:referenced_object]
        page_list.push *( pages(catalogs[:referenced_object]) )
      else
        warn "couldn't follow reference!!! #{catalogs} not found!"
      end
    else
      case catalogs[:Type]
      when :Page
        holder = self
        catalogs.define_singleton_method("<<".to_sym) do |obj|
          obj = PDFOperations.copy_and_secure_for_injection obj
          PDFOperations.inject_to_page self, obj
          holder.add_referenced obj
        end
        page_list << catalogs
      when :Pages
        page_list.push *(pages(catalogs[:Kids])) unless catalogs[:Kids].nil?
      when :Catalog
        page_list.push *(pages(catalogs[:Pages])) unless catalogs[:Pages].nil?
      end
    end
  end
  page_list
end

#rebuild_catalog(*with_pages) ⇒ Object 



284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 284

def rebuild_catalog(*with_pages)
  ##########################
  ## Test-Run - How is that done?
  warn "Re-Building Catalog"

  # # build page list v.1 Slow but WORKS
  # # Benchmark testing value: 26.708394
  # old_catalogs = @objects.select {|obj| obj.is_a?(Hash) && obj[:Type] == :Catalog}
  # old_catalogs ||= []
  # page_list = []
  # PDFOperations._each_object(old_catalogs,false) { |p| page_list << p if p.is_a?(Hash) && p[:Type] == :Page }

  # build page list v.2
  # Benchmark testing value: 0.215114
  page_list = pages

  # add pages to catalog, if requested
  page_list.push(*with_pages) unless with_pages.empty?

  # build new Pages object
  pages_object = {Type: :Pages, Count: page_list.length, Kids: page_list.map {|p| {referenced_object: p, is_reference_only: true} } }

  # build new Catalog object
  catalog_object = {Type: :Catalog, Pages: {referenced_object: pages_object, is_reference_only: true} }

  # point old Pages pointers to new Pages object
  ## first point known pages objects - enough?
  pages.each {|p| p[:Parent] = { referenced_object: pages_object, is_reference_only: true} }
  ## or should we, go over structure? (fails)
  # each_object {|obj| obj[:Parent][:referenced_object] = pages_object if obj.is_a?(Hash) && obj[:Parent].is_a?(Hash) && obj[:Parent][:referenced_object] && obj[:Parent][:referenced_object][:Type] == :Pages}

  # remove old catalog and pages objects
  @objects.reject! {|obj| obj.is_a?(Hash) && (obj[:Type] == :Catalog || obj[:Type] == :Pages) }

  # inject new catalog and pages objects
  @objects << pages_object
  @objects << catalog_object

  catalog_object
end

#rebuild_catalog_and_objects ⇒ Object

this is an alternative to the rebuild_catalog catalog method this method might eventually be used by the to_pdf method, for streamlining the PDF output.



326
327
328
329
330
331
332
333
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 326

def rebuild_catalog_and_objects
  catalog = rebuild_catalog
  @objects = []
  @objects << catalog
  add_referenced catalog
  renumber_object_ids
  catalog
end

#rebuild_resources ⇒ Object 



335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 335

def rebuild_resources

  warn "Resources re-building disabled as it isn't worth the price in peformance as of yet."

  return true

  warn "Re-Building Resources"
  @need_to_rebuild_resources = false
  # what are resources?
  # anything at the top level of the file exept catalogs, page lists (Pages) and pages...
  not_resources = [:Catalog, :Pages, :Page]
  # get old resources list
  old_resources = @objects.select {|obj| obj.is_a?(Hash) && !not_resources.include?(obj[:Type])}
  # collect all unique resources while ignoring double values and resetting references
  # also ignore inner values (canot use PRIVATE_HASH_KEYS because of stream and other issues)
  ignore_keys = [:indirect_reference_id, :indirect_generation_number, :is_reference_only, :referenced_object]
  new_resources = []
  all_references = references
  old_resources.each do |old_r|
    add = true
    new_resources.each do |new_r|
      # ## v.1.0 - slower
      # if (old_r.reject {|k,v| ignore_keys.include?(k) }) == (new_r.reject {|k,v| ignore_keys.include?(k)})
      #  all_references.each {|ref| ref[:referenced_object] = new_r if ref[:referenced_object].object_id == old_r.object_id }  # fails, but doesn't assume all references are connected: compare_reference_values(old_r, ref) }
      #  add = false
      # end
      ## v.1.1 - faster, doesn't build two hashes (but iterates one)
      if ( [].tap {|out| old_r.each {|k,v| out << true unless ((!ignore_keys.include?(k)) && new_r[k] == v) } } .empty?)
        all_references.each {|ref| ref[:referenced_object] = new_r if ref[:referenced_object].object_id == old_r.object_id }  # fails, but doesn't assume all references are connected: compare_reference_values(old_r, ref) }
        add = false
      end
    end
    new_resources << old_r if add
  end
  # remove old resources
  @objects.reject! {|obj| old_resources.include?(obj)}
  # insert new resources
  @objects.push *new_resources
  # rebuild stream lengths?
end

#references(indirect_reference_id = nil, indirect_generation_number = nil) ⇒ Object 



238
239
240
241
242
243
244
245
246
247
248
249
250
251
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 238

def references(indirect_reference_id = nil, indirect_generation_number = nil)
  ref = {indirect_reference_id: indirect_reference_id, indirect_generation_number: indirect_generation_number}
  out = []
  each_object do |obj|
    if obj[:is_reference_only]
      if (indirect_reference_id == nil && indirect_generation_number == nil)
        out << obj 
      elsif compare_reference_values(ref, obj)
        out << obj 
      end
    end
  end
  out
end

#renumber_object_ids(start = nil) ⇒ Object 



226
227
228
229
230
231
232
233
234
235
236
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 226

def renumber_object_ids(start = nil)
  warn "Resetting Object Reference IDs"
  @set_start_id ||= start
  start = @set_start_id
  history = {}
  all_indirect_object.each do |obj|
    obj[:indirect_reference_id] = start
    start += 1
  end
  warn "Finished serializing IDs"
end

#save(file_name) ⇒ Object

Seve the PDF to file. save(file_name)

  • file_name is a string or path object for the output.

Notice! if the file exists, it WILL be overwritten.



96
97
98
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 96

def save(file_name)
  IO.binwrite file_name, to_pdf
end

#serialize_objects_and_references(object = nil) ⇒ Object 



185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 185

def serialize_objects_and_references(object = nil)
  warn "connecting objects with their references (serialize_objects_and_references)."

  # # Version 3.5 injects indirect objects if they arn't dictionaries.
  # # benchmark 1000.times was 3.568246 sec for pdf = CombinePDF.new "/Users/2Be/Desktop/מוצגים/20121002\ הודעת\ הערעור.pdf" }
  # # puts Benchmark.measure { 1000.times {pdf.serialize_objects_and_references} }
  # # ######### Intreduces a BUG with catalogging pages... why? I don't know... mybey doesn't catch all.
  # each_object do |obj|
  #  obj.each do |k, v|
  #    if v.is_a?(Hash) && v[:is_reference_only]
  #      v[:referenced_object] = PDFOperations.get_refernced_object @objects, v
  #      raise "couldn't connect references" unless v[:referenced_object]
  #      obj[k] = v[:referenced_object][:indirect_without_dictionary] if v[:referenced_object][:indirect_without_dictionary]
  #    end
  #  end
  # end

  # Version 4
  # benchmark 1000.times was 0.980651 sec for:
  # pdf = CombinePDF.new "/Users/2Be/Desktop/מוצגים/20121002\ הודעת\ הערעור.pdf"
  # puts Benchmark.measure { 1000.times {pdf.serialize_objects_and_references} }
  objects_reference_hash = {}
  @objects.each {|o| objects_reference_hash[ [o[:indirect_reference_id], o[:indirect_generation_number] ] ] = o }
  each_object do |obj|
    if obj[:is_reference_only]
      obj[:referenced_object] = objects_reference_hash[ [obj[:indirect_reference_id], obj[:indirect_generation_number] ]   ]
      warn "couldn't connect a reference!!! could be a null object, Silent error!!!" unless obj[:referenced_object]
    end
  end

  # # Version 3
  # # benchmark 1000.times was 3.568246 sec for pdf = CombinePDF.new "/Users/2Be/Desktop/מוצגים/20121002\ הודעת\ הערעור.pdf" }
  # # puts Benchmark.measure { 1000.times {pdf.serialize_objects_and_references} }
  # each_object do |obj|
  #  if obj[:is_reference_only]
  #    obj[:referenced_object] = PDFOperations.get_refernced_object @objects, obj
  #    warn "couldn't connect a reference!!! could be a null object, Silent error!!!" unless obj[:referenced_object]
  #  end
  # end

end

#sort_objects_by_id ⇒ Object 



255
256
257
258
259
260
261
262
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 255

def sort_objects_by_id
  @objects.sort! do |a,b|
    if a.is_a?(Hash) && a[:indirect_reference_id] && a[:is_reference_only].nil? && b.is_a?(Hash) && b[:indirect_reference_id] && b[:is_reference_only].nil?
      return a[:indirect_reference_id] <=> b[:indirect_reference_id]
    end
    0
  end
end

#to_pdf ⇒ Object

Formats the data to PDF formats and returns a binary string that represents the PDF file content. This method is used by the save(file_name) method to save the content to a file. use this to export the PDF file without saving to disk (such as sending through HTTP ect’).



48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
 
# File 'lib/combine_pdf/combine_pdf_pdf.rb', line 48

def to_pdf
  #reset version if not specified
  @version = 1.3 if @version == 0
  #set creation date for merged file
  @info[:CreationDate] = Time.now.strftime "D:%Y%m%d%H%M%S%:::z'00"
  #rebuild resources if needed
  if @need_to_rebuild_resources
    rebuild_resources
  end
  catalog = rebuild_catalog_and_objects #rebuild_catalog

  warn "Formatting PDF output"

  out = []
  xref = []
  indirect_object_count = 1 #the first object is the null object
  #write head (version and binanry-code)
  out << "%PDF-#{@version.to_s}\n%\x00\x00\x00\x00".force_encoding(Encoding::ASCII_8BIT)

  #collect objects and set xref table locations
  loc = 0
  out.each {|line| loc += line.bytes.length + 1}
  @objects.each do |o|
    indirect_object_count += 1
    xref << loc
    out << PDFOperations._object_to_pdf(o)
    loc += out.last.length + 1
  end
  warn "Building XREF"
  xref_location = 0
  out.each { |line| xref_location += line.bytes.length + 1}
  out << "xref\n\r0 #{(indirect_object_count).to_s}\n\r0000000000 65535 f \n\r"
  xref.each {|offset| out << ( out.pop + ("%010d 00000 n \n\r" % offset) ) }
  out << out.pop + "trailer"
  out << "<<\n/Root #{false || "#{catalog[:indirect_reference_id]} #{catalog[:indirect_generation_number]} R"}"
  out << "/Size #{indirect_object_count.to_s}"
  if @info.is_a?(Hash)
    PRIVATE_HASH_KEYS.each {|key| @info.delete key} # make sure the dictionary is rendered inline, without stream
    out << "/Info #{PDFOperations._object_to_pdf @info}"
  end
  out << ">>\nstartxref\n#{xref_location.to_s}\n%%EOF"
  out.join("\n").force_encoding(Encoding::ASCII_8BIT)
end