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

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

Overview

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



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# File 'lib/json/pure/generator.rb', line 134

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

Instance Attribute Details

#array_nl ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 160

def array_nl
  @array_nl
end

#depth ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 168

def depth
  @depth
end

#indent ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 146

def indent
  @indent
end

#max_nesting ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 164

def max_nesting
  @max_nesting
end

#object_nl ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 157

def object_nl
  @object_nl
end

#space ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 150

def space
  @space
end

#space_before ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 153

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.



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# File 'lib/json/pure/generator.rb', line 108

def self.from_state(opts)
  case opts
  when self
    opts
  when Hash
    new(opts)
  else
    SAFE_STATE_PROTOTYPE.dup
  end
end

Instance Method Details

#[](name) ⇒ Object

Return the value returned by method name.



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# File 'lib/json/pure/generator.rb', line 236

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) 


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# File 'lib/json/pure/generator.rb', line 185

def allow_nan?
  @allow_nan
end

#ascii_only? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/json/pure/generator.rb', line 189

def ascii_only?
  @ascii_only
end

#check_circular? ⇒ Boolean

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

Returns:

  • (Boolean) 


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# File 'lib/json/pure/generator.rb', line 179

def check_circular?
  !@max_nesting.zero?
end

#check_max_nesting ⇒ Object

:nodoc:



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# File 'lib/json/pure/generator.rb', line 170

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

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



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# File 'lib/json/pure/generator.rb', line 195

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
  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.



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# File 'lib/json/pure/generator.rb', line 227

def generate(obj)
  result = obj.to_json(self)
  if result !~ /\A\s*(?:\[.*\]|\{.*\})\s*\Z/m
    raise GeneratorError, "only generation of JSON objects or arrays allowed"
  end
  result
end

#to_h ⇒ Object

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



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# File 'lib/json/pure/generator.rb', line 216

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