extern/json/lib/json/common.rb
require 'json/version'
require 'json/generic_object'
module JSON
class << self
# If _object_ is string-like, parse the string and return the parsed result
# as a Ruby data structure. Otherwise generate a JSON text from the Ruby
# data structure object and return it.
#
# The _opts_ argument is passed through to generate/parse respectively. See
# generate and parse for their documentation.
def [](object, opts = {})
if object.respond_to? :to_str
JSON.parse(object.to_str, opts)
else
JSON.generate(object, opts)
end
end
# Returns the JSON parser class that is used by JSON. This is either
# JSON::Ext::Parser or JSON::Pure::Parser.
attr_reader :parser
# Set the JSON parser class _parser_ to be used by JSON.
def parser=(parser) # :nodoc:
@parser = parser
remove_const :Parser if JSON.const_defined_in?(self, :Parser)
const_set :Parser, parser
end
# Return the constant located at _path_. The format of _path_ has to be
# either ::A::B::C or A::B::C. In any case, A has to be located at the top
# level (absolute namespace path?). If there doesn't exist a constant at
# the given path, an ArgumentError is raised.
def deep_const_get(path) # :nodoc:
path.to_s.split(/::/).inject(Object) do |p, c|
case
when c.empty? then p
when JSON.const_defined_in?(p, c) then p.const_get(c)
else
begin
p.const_missing(c)
rescue NameError => e
raise ArgumentError, "can't get const #{path}: #{e}"
end
end
end
end
# Set the module _generator_ to be used by JSON.
def generator=(generator) # :nodoc:
old, $VERBOSE = $VERBOSE, nil
@generator = generator
generator_methods = generator::GeneratorMethods
for const in generator_methods.constants
klass = deep_const_get(const)
modul = generator_methods.const_get(const)
klass.class_eval do
instance_methods(false).each do |m|
m.to_s == 'to_json' and remove_method m
end
include modul
end
end
self.state = generator::State
const_set :State, self.state
const_set :SAFE_STATE_PROTOTYPE, State.new
const_set :FAST_STATE_PROTOTYPE, State.new(
:indent => '',
:space => '',
:object_nl => "",
:array_nl => "",
:max_nesting => false
)
const_set :PRETTY_STATE_PROTOTYPE, State.new(
:indent => ' ',
:space => ' ',
:object_nl => "\n",
:array_nl => "\n"
)
ensure
$VERBOSE = old
end
# Returns the JSON generator module that is used by JSON. This is
# either JSON::Ext::Generator or JSON::Pure::Generator.
attr_reader :generator
# Returns the JSON generator state class that is used by JSON. This is
# either JSON::Ext::Generator::State or JSON::Pure::Generator::State.
attr_accessor :state
# This is create identifier, which is used to decide if the _json_create_
# hook of a class should be called. It defaults to 'json_class'.
attr_accessor :create_id
end
self.create_id = 'json_class'
NaN = 0.0/0
Infinity = 1.0/0
MinusInfinity = -Infinity
# The base exception for JSON errors.
class JSONError < StandardError
def self.wrap(exception)
obj = new("Wrapped(#{exception.class}): #{exception.message.inspect}")
obj.set_backtrace exception.backtrace
obj
end
end
# This exception is raised if a parser error occurs.
class ParserError < JSONError; end
# This exception is raised if the nesting of parsed data structures is too
# deep.
class NestingError < ParserError; end
# :stopdoc:
class CircularDatastructure < NestingError; end
# :startdoc:
# This exception is raised if a generator or unparser error occurs.
class GeneratorError < JSONError; end
# For backwards compatibility
UnparserError = GeneratorError
# This exception is raised if the required unicode support is missing on the
# system. Usually this means that the iconv library is not installed.
class MissingUnicodeSupport < JSONError; end
module_function
# Parse the JSON document _source_ into a Ruby data structure and return it.
#
# _opts_ can have the following
# keys:
# * *max_nesting*: The maximum depth of nesting allowed in the parsed data
# structures. Disable depth checking with :max_nesting => false. It defaults
# to 100.
# * *allow_nan*: If set to true, allow NaN, Infinity and -Infinity in
# defiance of RFC 4627 to be parsed by the Parser. This option defaults
# to false.
# * *symbolize_names*: If set to true, returns symbols for the names
# (keys) in a JSON object. Otherwise strings are returned. Strings are
# the default.
# * *create_additions*: If set to false, the Parser doesn't create
# additions even if a matching class and create_id was found. This option
# defaults to true.
# * *object_class*: Defaults to Hash
# * *array_class*: Defaults to Array
def parse(source, opts = {})
Parser.new(source, opts).parse
end
# Parse the JSON document _source_ into a Ruby data structure and return it.
# The bang version of the parse method defaults to the more dangerous values
# for the _opts_ hash, so be sure only to parse trusted _source_ documents.
#
# _opts_ can have the following keys:
# * *max_nesting*: The maximum depth of nesting allowed in the parsed data
# structures. Enable depth checking with :max_nesting => anInteger. The parse!
# methods defaults to not doing max depth checking: This can be dangerous
# if someone wants to fill up your stack.
# * *allow_nan*: If set to true, allow NaN, Infinity, and -Infinity in
# defiance of RFC 4627 to be parsed by the Parser. This option defaults
# to true.
# * *create_additions*: If set to false, the Parser doesn't create
# additions even if a matching class and create_id was found. This option
# defaults to true.
def parse!(source, opts = {})
opts = {
:max_nesting => false,
:allow_nan => true
}.update(opts)
Parser.new(source, opts).parse
end
# Generate a JSON document from the Ruby data structure _obj_ and return
# it. _state_ is * a JSON::State object,
# * or a Hash like object (responding to to_hash),
# * an object convertible into a hash by a to_h method,
# that is used as or to configure a State object.
#
# It defaults to a state object, that creates the shortest possible JSON text
# in one line, checks for circular data structures and doesn't allow NaN,
# Infinity, and -Infinity.
#
# A _state_ hash 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: ''),
# * *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.
# * *max_nesting*: The maximum depth of nesting allowed in the data
# structures from which JSON is to be generated. Disable depth checking
# with :max_nesting => false, it defaults to 100.
#
# See also the fast_generate for the fastest creation method with the least
# amount of sanity checks, and the pretty_generate method for some
# defaults for pretty output.
def generate(obj, opts = nil)
if State === opts
state, opts = opts, nil
else
state = SAFE_STATE_PROTOTYPE.dup
end
if opts
if opts.respond_to? :to_hash
opts = opts.to_hash
elsif opts.respond_to? :to_h
opts = opts.to_h
else
raise TypeError, "can't convert #{opts.class} into Hash"
end
state = state.configure(opts)
end
state.generate(obj)
end
# :stopdoc:
# I want to deprecate these later, so I'll first be silent about them, and
# later delete them.
alias unparse generate
module_function :unparse
# :startdoc:
# Generate a JSON document from the Ruby data structure _obj_ and return it.
# This method disables the checks for circles in Ruby objects.
#
# *WARNING*: Be careful not to pass any Ruby data structures with circles as
# _obj_ argument because this will cause JSON to go into an infinite loop.
def fast_generate(obj, opts = nil)
if State === opts
state, opts = opts, nil
else
state = FAST_STATE_PROTOTYPE.dup
end
if opts
if opts.respond_to? :to_hash
opts = opts.to_hash
elsif opts.respond_to? :to_h
opts = opts.to_h
else
raise TypeError, "can't convert #{opts.class} into Hash"
end
state.configure(opts)
end
state.generate(obj)
end
# :stopdoc:
# I want to deprecate these later, so I'll first be silent about them, and later delete them.
alias fast_unparse fast_generate
module_function :fast_unparse
# :startdoc:
# Generate a JSON document from the Ruby data structure _obj_ and return it.
# The returned document is a prettier form of the document returned by
# #unparse.
#
# The _opts_ argument can be used to configure the generator. See the
# generate method for a more detailed explanation.
def pretty_generate(obj, opts = nil)
if State === opts
state, opts = opts, nil
else
state = PRETTY_STATE_PROTOTYPE.dup
end
if opts
if opts.respond_to? :to_hash
opts = opts.to_hash
elsif opts.respond_to? :to_h
opts = opts.to_h
else
raise TypeError, "can't convert #{opts.class} into Hash"
end
state.configure(opts)
end
state.generate(obj)
end
# :stopdoc:
# I want to deprecate these later, so I'll first be silent about them, and later delete them.
alias pretty_unparse pretty_generate
module_function :pretty_unparse
# :startdoc:
class << self
# The global default options for the JSON.load method:
# :max_nesting: false
# :allow_nan: true
# :quirks_mode: true
attr_accessor :load_default_options
end
self.load_default_options = {
:max_nesting => false,
:allow_nan => true,
:quirks_mode => true,
:create_additions => true,
}
# Load a ruby data structure from a JSON _source_ and return it. A source can
# either be a string-like object, an IO-like object, or an object responding
# to the read method. If _proc_ was given, it will be called with any nested
# Ruby object as an argument recursively in depth first order. To modify the
# default options pass in the optional _options_ argument as well.
#
# BEWARE: This method is meant to serialise data from trusted user input,
# like from your own database server or clients under your control, it could
# be dangerous to allow untrusted users to pass JSON sources into it. The
# default options for the parser can be changed via the load_default_options
# method.
#
# This method is part of the implementation of the load/dump interface of
# Marshal and YAML.
def load(source, proc = nil, options = {})
opts = load_default_options.merge options
if source.respond_to? :to_str
source = source.to_str
elsif source.respond_to? :to_io
source = source.to_io.read
elsif source.respond_to?(:read)
source = source.read
end
if opts[:quirks_mode] && (source.nil? || source.empty?)
source = 'null'
end
result = parse(source, opts)
recurse_proc(result, &proc) if proc
result
end
# Recursively calls passed _Proc_ if the parsed data structure is an _Array_ or _Hash_
def recurse_proc(result, &proc)
case result
when Array
result.each { |x| recurse_proc x, &proc }
proc.call result
when Hash
result.each { |x, y| recurse_proc x, &proc; recurse_proc y, &proc }
proc.call result
else
proc.call result
end
end
alias restore load
module_function :restore
class << self
# The global default options for the JSON.dump method:
# :max_nesting: false
# :allow_nan: true
# :quirks_mode: true
attr_accessor :dump_default_options
end
self.dump_default_options = {
:max_nesting => false,
:allow_nan => true,
:quirks_mode => true,
}
# Dumps _obj_ as a JSON string, i.e. calls generate on the object and returns
# the result.
#
# If anIO (an IO-like object or an object that responds to the write method)
# was given, the resulting JSON is written to it.
#
# If the number of nested arrays or objects exceeds _limit_, an ArgumentError
# exception is raised. This argument is similar (but not exactly the
# same!) to the _limit_ argument in Marshal.dump.
#
# The default options for the generator can be changed via the
# dump_default_options method.
#
# This method is part of the implementation of the load/dump interface of
# Marshal and YAML.
def dump(obj, anIO = nil, limit = nil)
if anIO and limit.nil?
anIO = anIO.to_io if anIO.respond_to?(:to_io)
unless anIO.respond_to?(:write)
limit = anIO
anIO = nil
end
end
opts = JSON.dump_default_options
limit and opts.update(:max_nesting => limit)
result = generate(obj, opts)
if anIO
anIO.write result
anIO
else
result
end
rescue JSON::NestingError
raise ArgumentError, "exceed depth limit"
end
# Swap consecutive bytes of _string_ in place.
def self.swap!(string) # :nodoc:
0.upto(string.size / 2) do |i|
break unless string[2 * i + 1]
string[2 * i], string[2 * i + 1] = string[2 * i + 1], string[2 * i]
end
string
end
# Shortuct for iconv.
if ::String.method_defined?(:encode) &&
# XXX Rubinius doesn't support ruby 1.9 encoding yet
defined?(RUBY_ENGINE) && RUBY_ENGINE != 'rbx'
then
# Encodes string using Ruby's _String.encode_
def self.iconv(to, from, string)
string.encode(to, from)
end
else
require 'iconv'
# Encodes string using _iconv_ library
def self.iconv(to, from, string)
Iconv.conv(to, from, string)
end
end
if ::Object.method(:const_defined?).arity == 1
def self.const_defined_in?(modul, constant)
modul.const_defined?(constant)
end
else
def self.const_defined_in?(modul, constant)
modul.const_defined?(constant, false)
end
end
end
module ::Kernel
private
# Outputs _objs_ to STDOUT as JSON strings in the shortest form, that is in
# one line.
def j(*objs)
objs.each do |obj|
puts JSON::generate(obj, :allow_nan => true, :max_nesting => false)
end
nil
end
# Ouputs _objs_ to STDOUT as JSON strings in a pretty format, with
# indentation and over many lines.
def jj(*objs)
objs.each do |obj|
puts JSON::pretty_generate(obj, :allow_nan => true, :max_nesting => false)
end
nil
end
# If _object_ is string-like, parse the string and return the parsed result as
# a Ruby data structure. Otherwise, generate a JSON text from the Ruby data
# structure object and return it.
#
# The _opts_ argument is passed through to generate/parse respectively. See
# generate and parse for their documentation.
def JSON(object, *args)
if object.respond_to? :to_str
JSON.parse(object.to_str, args.first)
else
JSON.generate(object, args.first)
end
end
end
# Extends any Class to include _json_creatable?_ method.
class ::Class
# Returns true if this class can be used to create an instance
# from a serialised JSON string. The class has to implement a class
# method _json_create_ that expects a hash as first parameter. The hash
# should include the required data.
def json_creatable?
respond_to?(:json_create)
end
end