Class: PDF::Reader::ValidatingReceiver

Inherits:
Object
  • Object
show all
Defined in:
lib/pdf/reader/validating_receiver.rb

Overview

Page#walk will execute the content stream of a page, calling methods on a receiver class provided by the user. Each operator has a specific set of parameters it expects, and we wrap the users receiver class in this one to verify the PDF uses valid parameters.

Without these checks, users can’t be confident about the number of parameters they’ll receive for an operator, or what the type of those parameters will be. Everyone ends up building their own type safety guard clauses and it’s tedious.

Not all operators have type safety implemented yet, but we can expand the number over time.

Instance Method Summary collapse

Constructor Details

#initialize(wrapped) ⇒ ValidatingReceiver

Returns a new instance of ValidatingReceiver.



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# File 'lib/pdf/reader/validating_receiver.rb', line 19

def initialize(wrapped)
  @wrapped = wrapped
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(methodname, *args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 251

def method_missing(methodname, *args)
  @wrapped.send(methodname, *args)
end

Instance Method Details

#begin_inline_image(*args) ⇒ Object

Inline Image Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 224

def begin_inline_image(*args)
  call_wrapped(:begin_inline_image)
end

#begin_inline_image_data(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 228

def begin_inline_image_data(*args)
  # We can't use call_wrapped() here because sorbet won't allow splat args with a dynamic
  # number of elements
  @wrapped.begin_inline_image_data(*args) if @wrapped.respond_to?(:begin_inline_image_data)
end

#begin_text_object(*args) ⇒ Object

Text Object Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 59

def begin_text_object(*args)
  call_wrapped(:begin_text_object)
end

#concatenate_matrix(*args) ⇒ Object

Matrix Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 42

def concatenate_matrix(*args)
  a, b, c, d, e, f = *args
  call_wrapped(
    :concatenate_matrix,
    TypeCheck.cast_to_numeric!(a),
    TypeCheck.cast_to_numeric!(b),
    TypeCheck.cast_to_numeric!(c),
    TypeCheck.cast_to_numeric!(d),
    TypeCheck.cast_to_numeric!(e),
    TypeCheck.cast_to_numeric!(f),
  )
end

#end_inline_image(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 234

def end_inline_image(*args)
  data, _ = *args

  call_wrapped(
    :end_inline_image,
    TypeCheck.cast_to_string!(data)
  )
end

#end_text_object(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 63

def end_text_object(*args)
  call_wrapped(:end_text_object)
end

#invoke_xobject(*args) ⇒ Object

Form XObject Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 211

def invoke_xobject(*args)
  label, _ = *args

  call_wrapped(
    :invoke_xobject,
    TypeCheck.cast_to_symbol(label)
  )
end

#move_text_position(*args) ⇒ Object

Text Positioning Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 131

def move_text_position(*args) # Td
  x, y, _ = *args
  call_wrapped(
    :move_text_position,
    TypeCheck.cast_to_numeric!(x),
    TypeCheck.cast_to_numeric!(y)
  )
end

#move_text_position_and_set_leading(*args) ⇒ Object

TD



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# File 'lib/pdf/reader/validating_receiver.rb', line 140

def move_text_position_and_set_leading(*args) # TD
  x, y, _ = *args
  call_wrapped(
    :move_text_position_and_set_leading,
    TypeCheck.cast_to_numeric!(x),
    TypeCheck.cast_to_numeric!(y)
  )
end

#move_to_next_line_and_show_text(*args) ⇒ Object

‘



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# File 'lib/pdf/reader/validating_receiver.rb', line 189

def move_to_next_line_and_show_text(*args) # '
  string, _ = *args
  call_wrapped(
    :move_to_next_line_and_show_text,
    TypeCheck.cast_to_string!(string)
  )
end

#move_to_start_of_next_line(*args) ⇒ Object

T*



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# File 'lib/pdf/reader/validating_receiver.rb', line 162

def move_to_start_of_next_line(*args) # T*
  call_wrapped(:move_to_start_of_next_line)
end

#page=(page) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 23

def page=(page)
  call_wrapped(:page=, page)
end

#respond_to?(meth) ⇒ Boolean

Final safety net for any operators that don’t have type checking enabled yet

Returns:

  • (Boolean) 


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# File 'lib/pdf/reader/validating_receiver.rb', line 247

def respond_to?(meth)
  @wrapped.respond_to?(meth)
end

#restore_graphics_state(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 34

def restore_graphics_state(*args)
  call_wrapped(:restore_graphics_state)
end

#save_graphics_state(*args) ⇒ Object

Graphics State Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 30

def save_graphics_state(*args)
  call_wrapped(:save_graphics_state)
end

#set_character_spacing(*args) ⇒ Object

Text State Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 70

def set_character_spacing(*args)
  char_spacing, _ = *args
  call_wrapped(
    :set_character_spacing,
    TypeCheck.cast_to_numeric!(char_spacing)
  )
end

#set_horizontal_text_scaling(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 78

def set_horizontal_text_scaling(*args)
  h_scaling, _ = *args
  call_wrapped(
    :set_horizontal_text_scaling,
    TypeCheck.cast_to_numeric!(h_scaling)
  )
end

#set_spacing_next_line_show_text(*args) ⇒ Object

“



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# File 'lib/pdf/reader/validating_receiver.rb', line 197

def set_spacing_next_line_show_text(*args) # "
  aw, ac, string = *args
  call_wrapped(
    :set_spacing_next_line_show_text,
    TypeCheck.cast_to_numeric!(aw),
    TypeCheck.cast_to_numeric!(ac),
    TypeCheck.cast_to_string!(string)
  )
end

#set_text_font_and_size(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 86

def set_text_font_and_size(*args)
  label, size, _ = *args
  call_wrapped(
    :set_text_font_and_size,
    TypeCheck.cast_to_symbol(label),
    TypeCheck.cast_to_numeric!(size)
  )
end

#set_text_leading(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 95

def set_text_leading(*args)
  leading, _ = *args
  call_wrapped(
    :set_text_leading,
    TypeCheck.cast_to_numeric!(leading)
  )
end

#set_text_matrix_and_text_line_matrix(*args) ⇒ Object

Tm



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# File 'lib/pdf/reader/validating_receiver.rb', line 149

def set_text_matrix_and_text_line_matrix(*args) # Tm
  a, b, c, d, e, f = *args
  call_wrapped(
    :set_text_matrix_and_text_line_matrix,
    TypeCheck.cast_to_numeric!(a),
    TypeCheck.cast_to_numeric!(b),
    TypeCheck.cast_to_numeric!(c),
    TypeCheck.cast_to_numeric!(d),
    TypeCheck.cast_to_numeric!(e),
    TypeCheck.cast_to_numeric!(f),
  )
end

#set_text_rendering_mode(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 103

def set_text_rendering_mode(*args)
  mode, _ = *args
  call_wrapped(
    :set_text_rendering_mode,
    TypeCheck.cast_to_numeric!(mode)
  )
end

#set_text_rise(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 111

def set_text_rise(*args)
  rise, _ = *args
  call_wrapped(
    :set_text_rise,
    TypeCheck.cast_to_numeric!(rise)
  )
end

#set_word_spacing(*args) ⇒ Object 



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# File 'lib/pdf/reader/validating_receiver.rb', line 119

def set_word_spacing(*args)
  word_spacing, _ = *args
  call_wrapped(
    :set_word_spacing,
    TypeCheck.cast_to_numeric!(word_spacing)
  )
end

#show_text(*args) ⇒ Object

Text Showing Operators



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# File 'lib/pdf/reader/validating_receiver.rb', line 169

def show_text(*args) # Tj (AWAY)
  string, _ = *args
  call_wrapped(
    :show_text,
    TypeCheck.cast_to_string!(string)
  )
end

#show_text_with_positioning(*args) ⇒ Object

TJ [(A) 120 (WA) 20 (Y)]



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# File 'lib/pdf/reader/validating_receiver.rb', line 177

def show_text_with_positioning(*args) # TJ [(A) 120 (WA) 20 (Y)]
  params, _ = *args
  unless params.is_a?(Array)
    raise MalformedPDFError, "TJ operator expects a single Array argument"
  end

  call_wrapped(
    :show_text_with_positioning,
    params
  )
end