class PDF::Reader::ValidatingReceiver
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.
Public Class Methods
# File lib/pdf/reader/validating_receiver.rb, line 19 def initialize(wrapped) @wrapped = wrapped end
Public Instance Methods
Inline Image Operators
# File lib/pdf/reader/validating_receiver.rb, line 224 def begin_inline_image(*args) call_wrapped(:begin_inline_image) end
# 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
Text Object Operators
# File lib/pdf/reader/validating_receiver.rb, line 59 def begin_text_object(*args) call_wrapped(:begin_text_object) end
Matrix Operators
# 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
# 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
# File lib/pdf/reader/validating_receiver.rb, line 63 def end_text_object(*args) call_wrapped(:end_text_object) end
Form XObject Operators
# 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
# File lib/pdf/reader/validating_receiver.rb, line 251 def method_missing(methodname, *args) @wrapped.send(methodname, *args) end
Text Positioning Operators
# 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
# 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
# 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
# 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
# File lib/pdf/reader/validating_receiver.rb, line 23 def page=(page) call_wrapped(:page=, page) end
Final safety net for any operators that don’t have type checking enabled yet
# File lib/pdf/reader/validating_receiver.rb, line 247 def respond_to?(meth) @wrapped.respond_to?(meth) end
# File lib/pdf/reader/validating_receiver.rb, line 34 def restore_graphics_state(*args) call_wrapped(:restore_graphics_state) end
Graphics State Operators
# File lib/pdf/reader/validating_receiver.rb, line 30 def save_graphics_state(*args) call_wrapped(:save_graphics_state) end
Text State Operators
# 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
# 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
# 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
# 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
# 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
# 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
# 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
# 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
# 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
Text Showing Operators
# 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
# 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
Private Instance Methods
# File lib/pdf/reader/validating_receiver.rb, line 257 def call_wrapped(methodname, *args) @wrapped.send(methodname, *args) if @wrapped.respond_to?(methodname) end