Class: JSON::Pure::Generator::State

Inherits:
Object
  • Object
show all
Defined in:
lib/ghi/json.rb

Overview

This class is used to create State instances, that are use to hold data while generating a JSON text from a Ruby data structure.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(opts = {}) ⇒ State

Instantiates a new State object, configured by opts.

opts can have the following keys:

  • indent: a string used to indent levels (default: ”),

  • space: a string that is put after, a : or , delimiter (default: ”),

  • space_before: a string that is put before a : pair delimiter (default: ”),

  • object_nl: a string that is put at the end of a JSON object (default: ”),

  • array_nl: a string that is put at the end of a JSON array (default: ”),

  • check_circular: is deprecated now, use the :max_nesting option instead,

  • max_nesting: sets the maximum level of data structure nesting in the generated JSON, max_nesting = 0 if no maximum should be checked.

  • allow_nan: true if NaN, Infinity, and -Infinity should be generated, otherwise an exception is thrown, if these values are encountered. This options defaults to false.

  • quirks_mode: Enables quirks_mode for parser, that is for example generating single JSON values instead of documents is possible.



499
500
501
502
503
504
505
506
507
508
509
510
# File 'lib/ghi/json.rb', line 499

def initialize(opts = {})
  @indent                = ''
  @space                 = ''
  @space_before          = ''
  @object_nl             = ''
  @array_nl              = ''
  @allow_nan             = false
  @ascii_only            = false
  @quirks_mode           = false
  @buffer_initial_length = 1024
  configure opts
end

Instance Attribute Details

#array_nlObject

This string is put at the end of a line that holds a JSON array.



527
528
529
# File 'lib/ghi/json.rb', line 527

def array_nl
  @array_nl
end

#buffer_initial_lengthObject

:stopdoc:



538
539
540
# File 'lib/ghi/json.rb', line 538

def buffer_initial_length
  @buffer_initial_length
end

#depthObject

This integer returns the current depth data structure nesting in the generated JSON.



549
550
551
# File 'lib/ghi/json.rb', line 549

def depth
  @depth
end

#indentObject

This string is used to indent levels in the JSON text.



513
514
515
# File 'lib/ghi/json.rb', line 513

def indent
  @indent
end

#max_nestingObject

This integer returns the maximum level of data structure nesting in the generated JSON, max_nesting = 0 if no maximum is checked.



531
532
533
# File 'lib/ghi/json.rb', line 531

def max_nesting
  @max_nesting
end

#object_nlObject

This string is put at the end of a line that holds a JSON object (or Hash).



524
525
526
# File 'lib/ghi/json.rb', line 524

def object_nl
  @object_nl
end

#quirks_modeObject

If this attribute is set to true, quirks mode is enabled, otherwise it’s disabled.



535
536
537
# File 'lib/ghi/json.rb', line 535

def quirks_mode
  @quirks_mode
end

#spaceObject

This string is used to insert a space between the tokens in a JSON string.



517
518
519
# File 'lib/ghi/json.rb', line 517

def space
  @space
end

#space_beforeObject

This string is used to insert a space before the ‘:’ in JSON objects.



520
521
522
# File 'lib/ghi/json.rb', line 520

def space_before
  @space_before
end

Class Method Details

.from_state(opts) ⇒ Object

Creates a State object from opts, which ought to be Hash to create a new State instance configured by opts, something else to create an unconfigured instance. If opts is a State object, it is just returned.



469
470
471
472
473
474
475
476
477
478
479
480
# File 'lib/ghi/json.rb', line 469

def self.from_state(opts)
  case
  when self === opts
    opts
  when opts.respond_to?(:to_hash)
    new(opts.to_hash)
  when opts.respond_to?(:to_h)
    new(opts.to_h)
  else
    SAFE_STATE_PROTOTYPE.dup
  end
end

Instance Method Details

#[](name) ⇒ Object

Return the value returned by method name.



630
631
632
# File 'lib/ghi/json.rb', line 630

def [](name)
  __send__ name
end

#allow_nan?Boolean

Returns true if NaN, Infinity, and -Infinity should be considered as valid JSON and output.

Returns:

  • (Boolean)


566
567
568
# File 'lib/ghi/json.rb', line 566

def allow_nan?
  @allow_nan
end

#ascii_only?Boolean

Returns true, if only ASCII characters should be generated. Otherwise returns false.

Returns:

  • (Boolean)


572
573
574
# File 'lib/ghi/json.rb', line 572

def ascii_only?
  @ascii_only
end

#check_circular?Boolean

Returns true, if circular data structures are checked, otherwise returns false.

Returns:

  • (Boolean)


560
561
562
# File 'lib/ghi/json.rb', line 560

def check_circular?
  !@max_nesting.zero?
end

#check_max_nestingObject

:nodoc:



551
552
553
554
555
556
# File 'lib/ghi/json.rb', line 551

def check_max_nesting # :nodoc:
  return if @max_nesting.zero?
  current_nesting = depth + 1
  current_nesting > @max_nesting and
    raise NestingError, "nesting of #{current_nesting} is too deep"
end

#configure(opts) ⇒ Object Also known as: merge

Configure this State instance with the Hash opts, and return itself.



583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
# File 'lib/ghi/json.rb', line 583

def configure(opts)
  @indent         = opts[:indent] if opts.key?(:indent)
  @space          = opts[:space] if opts.key?(:space)
  @space_before   = opts[:space_before] if opts.key?(:space_before)
  @object_nl      = opts[:object_nl] if opts.key?(:object_nl)
  @array_nl       = opts[:array_nl] if opts.key?(:array_nl)
  @allow_nan      = !!opts[:allow_nan] if opts.key?(:allow_nan)
  @ascii_only     = opts[:ascii_only] if opts.key?(:ascii_only)
  @depth          = opts[:depth] || 0
  @quirks_mode    = opts[:quirks_mode] if opts.key?(:quirks_mode)
  if !opts.key?(:max_nesting) # defaults to 19
    @max_nesting = 19
  elsif opts[:max_nesting]
    @max_nesting = opts[:max_nesting]
  else
    @max_nesting = 0
  end
  self
end

#generate(obj) ⇒ Object

Generates a valid JSON document from object obj and returns the result. If no valid JSON document can be created this method raises a GeneratorError exception.



617
618
619
620
621
622
623
624
625
626
627
# File 'lib/ghi/json.rb', line 617

def generate(obj)
  result = obj.to_json(self)
  unless @quirks_mode
    unless result =~ /\A\s*\[/ && result =~ /\]\s*\Z/ ||
      result =~ /\A\s*\{/ && result =~ /\}\s*\Z/
    then
      raise GeneratorError, "only generation of JSON objects or arrays allowed"
    end
  end
  result
end

#quirks_mode?Boolean

Returns true, if quirks mode is enabled. Otherwise returns false.

Returns:

  • (Boolean)


577
578
579
# File 'lib/ghi/json.rb', line 577

def quirks_mode?
  @quirks_mode
end

#to_hObject

Returns the configuration instance variables as a hash, that can be passed to the configure method.



606
607
608
609
610
611
612
# File 'lib/ghi/json.rb', line 606

def to_h
  result = {}
  for iv in %w[indent space space_before object_nl array_nl allow_nan max_nesting ascii_only quirks_mode buffer_initial_length depth]
    result[iv.intern] = instance_variable_get("@#{iv}")
  end
  result
end